Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

93 Chevy Z71 heitates, now dies when door is shut


First page Previous page 1 2 Next page Last page  View All Email This Post



lesgohuntn
User

Dec 27, 2014, 6:06 PM

Post #1 of 28 (1510 views)
93 Chevy Z71 heitates, now dies when door is shut Sign In

First time user, so bare with me, please. Bought truck new. 93 chevy z71, 5.7 350, tbi Never got great mileage (12- 14 mpg). Probably 6 years old, started loosing power as I accelerated, but when I eased off on throttle, it would pick up and take off. Mileage dropped to 9- 10 mpg. I accidentally blew my motor up in an ice storm, and put in a crate motor, but used old tbi. Long story short.. 5 mechanics, 4 different Diagnostic hook ups (with 4 diff machines that all showed nothing wrong), and several years passed, as I was just driving it with the hesitation. I told my main mechanic to throw parts at it. Replaced fuel filter, wires, plugs, distributor cap, jets in tbi , vacuum checked, fuel pump, computer, every relay and sensor on truck... finally called me and asked me to come get it, he wouldn't even charge me labor nor some of the parts, because it stomped him! Few years later, an older Chevrolet tech said replace whole tbi. I did. mileage jumped to 15+ mpg, and ran like a charm for 3 months. Started again.. mpg 7- 8 ! Was going to replace tbi again, but when I hit a bump, engine dies, but fired right back up. Then it would die and have to wait 10- 30 min before it would fire up. Then you shut the door, it would die. Now it will not crank at all! I have traced wires, vacuums, check fuel flow, etc. Can anyone help me? I don't have a clue were to go from here, and cannot afford any more trips to mechanic.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 27, 2014, 7:34 PM

Post #2 of 28 (1496 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

All "crank, no start" conditions are approached in the same way. Every engine requires certain functions to be able to run. Some of these functions rely on specific components to work and some components are part of more than one function so it is important to see the whole picture to be able to conclude anything about what may have failed. Also, these functions can ONLY be tested during the failure. Any other time and they will simply test good because the problem isn't present at the moment.
If you approach this in any other way, you are merely guessing and that only serves to replace unnecessary parts and wastes money.



Every engine requires spark, fuel and compression to run. That's what we have to look for.

These are the basics that need to be tested and will give us the info required to isolate a cause.

1) Test for spark at the plug end of the wire using a spark tester. If none found, check for power supply on the + terminal of the coil with the key on.


2) Test for injector pulse using a small bulb called a noid light. If none found, check for power supply at one side of the injector with the key on.


3) Use a fuel pressure gauge to test for correct fuel pressure, also noticing if the pressure holds when key is shut off.

4) If all of these things check good, then you would need to do a complete compression test.

Once you have determined which of these functions has dropped out,
you will know which system is having the problem.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



lesgohuntn
User

Dec 27, 2014, 8:49 PM

Post #3 of 28 (1489 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Every time I try to work on it, it runs fine, shutting door, or hitting a bump will not shut engine off. But if I try to go somewhere in it, bump kills it. When I finally made it home, It won't do it so I can diagnose it. Hopefully, now you have given me a list of where to start, and the fact it wouldn't crank at all the last time I tried to, maybe I will have some luck. I'll have to see if I can afford the fuel pres. gauge, comp. tester, and spark tester, to run the tests. (I've always used the grounding the removed plug method for checking spark, but one of your moderators put that method down pretty bad to another poster)
In your opinion, as I believe, do you think the hesitation and bump killing the engine are 2 separate problems?
Thanks, and I'll get back to you when I can afford the testers required, and preform tests.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 27, 2014, 8:52 PM

Post #4 of 28 (1486 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

We're never going to know un til we get some info from these tests. The spark tester and noid lights can usually be bought for under $10. The fuel pressure gauge and comporession tester can usually be rented or borrowed from one of the chain part stores like Autozone or Advance auto.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 28, 2014, 3:52 AM

Post #5 of 28 (1478 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Quote from post #3 ">>Hopefully, now you have given me a list of where to start, and the fact it wouldn't crank at all the last time I tried to, maybe I will have some luck.<<"


Yikes - you hit a bump, truck totally dies then guess it must start and run again later so testing much is going to show it works.


Does this reset clock and radio also when this can happen? You may have a total disconnect of power and ground all to be checked battery to starter (+) battery to engine block (-) and straps from block to body in view and look for those that aren't. I thing one might be seen from trans to motor area as well.


The grounding plug to check for spark just isn't the best at all. Use an in line tester (cheap enough) but doubt that cause all this.


If this just goes total dead - everything then later starts and runs like nothing wrong you've lost all power and ground somewhere as said,


T



lesgohuntn
User

Dec 28, 2014, 9:00 AM

Post #6 of 28 (1470 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

The clock and radio never resets. I've checked the grounds and even considered adding extra grounds to bypass old ones to see if that helped, but been down in my back so haven't attempted yet. My Dad has a 92 z71, his did something very similar, and his mechanic put an ignition module (under rotor button in distributer), his ran like new. I tried it (shot in the dark) on mine, it ran good for the test drive, but when I turned in my driveway.... died again and too 15 min or so before it cranked again! I thought it maybe was getting hot if the old heat resistant grease was failing, and when I installed the new one, I applied the new grease supplied. It's been like a needle in a hay stack! If I didn't just love my old truck, I'd give it away, but she's very sentimental to me. Sentimental has been very expensive for me though.. lol


(This post was edited by lesgohuntn on Dec 28, 2014, 9:07 AM)


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 28, 2014, 9:45 AM

Post #7 of 28 (1467 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Just to clarify - You keep saying "CRANK" as in when it dies it doesn't turn or CRANK engine and think you mean it just doesn't start - huge difference!
Lost until we know and go back to post of testing an ALL CRANK, NO START post above and do the tests. What's missing and you don't know - right?


Clock or radio staying on suggests strongly you are not losing 100% of battery power so what does the sound make when you try to start it and if not certain do you see the fan on the engine turn when trying along with belt(s) turning?


Just FYI - something that happened to work on another vehicle means almost nothing,


T



lesgohuntn
User

Dec 28, 2014, 11:56 AM

Post #8 of 28 (1458 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

First off, FYI when you've had issues for so long, tried every thing, and many mechanical minds, nor myself, can't find what the problem is, trying something that fix a very similar problem on another 5.7 that is just like mine means everything (you said "means nothing") The part cost a lot less than many hours of paying a mechanic to not find anything, was well worth the effort to me! That being said now, to the other clarifications: When I say "crank", I mean I turn the key and the engine starts up and continues to run. When I say "won't crank" it means I turn the key and the engine turns over but will not start, or fires up a little, but goes dead instantly. If key is turned and engine doesn't turn at all, that is in my terms "Will not turn over".
Serpentine belt turns everything and all pulleys turn as I try to "crank it" or in your terms (I think) "no start".
The engine doesn't make any unusual noises, nor sound like it is in any strain as I turn it over. It just turns over and over. Then later, I turn the key, and it fires up as if nothing was ever wrong. Which has led me to believe at times, it is heat related. But just when I buy into heat related, I'll crank it up while engine is cold, shut the door, and... it dies! I immediately try to diagnose it, and fire it back up, Slam door several times, and it will not go dead!
Still, the whole problem comes back every time to the fact it cranks sometimes, it doesn't crank and run sometimes, and EVERY TIME I try to work on it, it will run fine. I mean how do you track that down??? But I go to use the truck, it gets me down the road and goes dead. When I get it fired back up and to the house, it won't do it! Just very frustrated that it is getting the worst out of me!!


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 28, 2014, 1:11 PM

Post #9 of 28 (1455 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Turn over and Crank mean the exact same thing. You have what we cal a "Crank, no start"


Quote
trying something that fix a very similar problem on another 5.7 that is just like mine means everything (you said "means nothing")


No, it means nothing. There can be dozens of different causes for the same symptoms and what fixes one car usually has absolutely nothing to do with the other, especially when your only like symptom is that it won't start.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



lesgohuntn
User

Dec 28, 2014, 2:02 PM

Post #10 of 28 (1452 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

OK. I'm from the South, so what I've understood my whole life must be different in mechanical terms. My bad. But, not trying to argue, after all the problems tracking and not finding, I feel, with the low cost for the part, it was worth a try. But I get where ya'll are coming from: don't replace parts until you know what part to replace. I get it. It was just an act of desperation! Thank you, and I'll try to use terms ya,ll are accustomed to from now on, as I see how what I say is confusing to you. Thanks again


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 28, 2014, 3:35 PM

Post #11 of 28 (1446 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

This isn't a debate you need to know if an engine cranks or just doesn't do anything at all. The word turnover always confuses it. Not a North or South, East or West anything.


Had you checked for spark in second post as suggested you wouldn't have bothered more checking much about an ignition problem and not changed a module if free why do that unless these had a very strong history of them going bad in that manner and they don't. Now what you do know since it wasn't the problem that is NOT the problem and mark the old one good and use it if it ever is the problem.


Understood this is a real and annoying problem you state happens by bumps and just shutting a door. So, if it has time while it just cranks and doesn't start that's when you check for what is missing, usually it would just lose any spark or not have fuel delivered. Have test stuff at the ready for WHEN it's not starting.


It's actually harder in that it eventually does start as then you question if testing was valid or not. At least you could either test fuel pressure or prime it with fuel and if a quick start up and die out you know to look on for fuel issues. No spark can be done alone and not going to bother explaining for this engine would be better to have a helper crank the engine with a spark tester (just a light up thing between plug wire and plug) and watch if it lights while being cranked by the helper.


Will be difficult if it doesn't stay in the all crank not starting mode long enough to test,


T



Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 28, 2014, 3:50 PM

Post #12 of 28 (1440 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

What I would do is let the truck idle and go around jiggling wire harnesses and plugs and tapping on electrical components, especially the ECM and see if you can trigger a stall.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



lesgohuntn
User

Dec 28, 2014, 5:24 PM

Post #13 of 28 (1435 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

This is precisely the aggravation I'm dealing with, is it won't stay in the all crank no start mode long enough for me to diagnose. I'm sorry my terminology creates confusion. I'm still trying to learn what to say to get ya'll to understand. The module I changed was before I found this site, so I didn't ignore the instructions ya'll gave me, I had already made that mistake before being on told here how to approach the diagnosing. Thanks for being patient with me, and when I'm able to get the right tools to do a real diagnosis, I know the info you have given will be of great help.


lesgohuntn
User

Dec 28, 2014, 5:29 PM

Post #14 of 28 (1433 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Hammertime, I have tried the jiggling method to no success, but ya'll have given me more info that I believe will be very helpful, once I'm able to get back to it. Thank you both very much, and I keep you posted if I have any success next time around.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 29, 2014, 2:11 AM

Post #15 of 28 (1426 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Thoughts and some mostly free things to do and try:


When you get something intermittent like this you may NOT be sure what fixed it unless boldly wrong something in sight. Then it's still hard to trust for a period of time that you won't get stuck again with the issue. It stinks.


Things that could add up and good to do on this and many vehicles but let's concentrate on GM and a body (metal) on chassis vehicle - any really.


Frame is actually isolated from the battery power as is engine and drivetrain by rubber parts so it needs the grounding either direct from the battery to body metal or engine block to body metal. That is repeated thru a vehicle to double up on grounding metal such that you don't need to constantly run a separate wire for assorted things for ground you just use body metal.


Parts of body are welded, bolted or hinged so these straps are added. Truck beds are actually isolated so need another jump to frame or more.


Frame is not rigid and does flex plus exposed to vibrations, bumps, heat, cold, wet, dry and let's toss in corrosion! Even more that escapes me for now.


So, you can ADD grounds on suspect areas or when you see those straps usually bolted clean them up wire brush or sandpaper with a smear of grease and put back. Include battery cables at batter GM sideposts are handy but hide corrosion and remarkable at fooling people the because the bolt it tight it must be good - NOT. That bolt requires the hidden eyelet to be good as well. That spot for now and this problem is not the likely problem but while in the course of care check those, grease or at least WD-40 like these things periodically and they rarely act up a LOT older than this truck even a lot more exposed to the elements than the South usually offers either with extremes.


You can test with decent jumper cables to harmless frame area to engine block and again block or frame back to body parts made of metal. Nice to have plain grounded things known and be done with that in the mix.


Neg battery cable to side (on this) of engine block is also a problem sometimes and intermittent. In the course of both time and if engine or other work requires it get removed and put back or forgotten forever, tugged on doing something else and so on.
Noted: This happens when you hit bumps or close the door that also suggests you just got in and put weight on the body to frame plus the whack of door closing made for just enough loss to mess it up still unknown where for sure. In short, you know what can trigger the problem hence you were advised the good ole "wiggle test" of things just no luck yet.


Wiring plugs all thru the thing matter especially those exposed to weather. Wires and plugs to anything to do with fuel delivery especially right down under and at fuel pump wiring.


Any maker but GM uses a lot of that greenish rubber bellows at some connections to keep moisture out then later can keep a leaking one from moisture drying out so they rot out and quit intermittently or all at once and stay as if disconnected which is much easier to locate so plain looking for corrosion on known essential items is in order.


If you take one or any connection in wiring apart and find a dry crusty maybe green or white mess there's a problem there. Some you need a new or better used exact plug than the one you find. Hello junk yarding for some.


The plastic bails and clips don't age well and frequently break that are meant to hold them together tightly. Sh*t, now what to do as nothing is really available new so many good wire ties can hold those tight again.


Grease those connections with "dietetic" or ask for "electrical grease" which is near impossible to rinse off or wash away easily. It also shouldn't conduct electricity by itself and is very rubber and plastic friendly. Also can call it Silicone grease. Stuff does cost but you don't need much to do the trick.


If you want things to last about forever (my middle name) you have to do this assertively.


In short you can prevent the next hair pulling issue with care along the way,


T



lesgohuntn
User

Dec 29, 2014, 11:11 AM

Post #16 of 28 (1418 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

I'm not so sure, but do you have some Southern blood in you?... wire ties? (just joking) We use wire ties, hay bailing twine, zip ties, and duct tape for everything around here! lol No, really a great idea, as I have encountered several of these plastic bails and clips, on this truck and many other vehicles, and never once thought of wire tie to help keep them snug! I have the electrical grease on hand already as I am a residential builder, and do a lot of electrical work.. just haven't thought to use it on DC connections.

I can't wait to get back to work on this thing, armed with so much more knowledge, tips, ideas, and more confidence both of you have given me (and much appreciated), but it has been raining here the last 2 days, and I currently have no where to get the truck in out of the rain to work on it. Great site ya'll have going here! And great minds giving advise! Thank you, and when I am able to get back to it, I'll post when I get any results (or failures).


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 29, 2014, 1:10 PM

Post #17 of 28 (1409 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

It's called "Yankee Ingenuity" and I really don't mean hack things up but things break you just are not going to find so do something that is safe and lasts.


The synthetics really work. I don't even oil a door hinge with regular oil then grease over that. I've had some untold hundreds of vehicles given to me in need of just too much mostly labor crap but sound major engine and trans plus little to no rust as that's the killer for anything where I am.


Was useful with any grease but permanent with the better stuff for assorted things. Not just cars stuff - use it on dang garden hoses that never come apart, faucet washers, wadding for sill cocks and more - anything that moves. Don't get that on anything you ever want to paint!


Back: Wiring and other things for cars slowly ended certain metal. You will find much less copper and brass for anything and lead (Pb) is gone for battery cable ends, mercury not allowed for switches even!


Point is plastic and rubber things are not forever flexible or hold tight. I can't see giving up on a good vehicle over stupid stuff like that.


If in all this didn't say and it is a wild guess is that wires on way to fuel pump should have a connector and your trouble is there and you would know better if quiet when down you won't hear the fuel pump prime up (buzz) for a couple seconds with key just turned to run not the start position. Didn't check where it is if not that a fuel pump relay if used this model year suspect too. Most of those if caught I just whack them and if they work instantly toss it for new,


T



lesgohuntn
User

Dec 30, 2014, 2:34 PM

Post #18 of 28 (1388 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Tom and/ or HT, I definitely have ALL CRANK/ NO START now. I turned the IGN. to run and the fuel pump runs, but not for the 4 or so seconds it normally does. It runs for a full 10+ seconds, and continually sounds weaker the longer it runs. (I've never heard it get weaker before.) I'm not sure if it gets weaker as it builds up pressure, or what, but if it was building pressure, it should be delivering fuel to TBI, as I've already replaced fuel filter? Or reckon the fuel pump is just too weak to deliver fuel? I tried to rent fuel press. tester, at local Auto Zone (the only place in 20 miles of me), $165.28 to rent (I don't have that much money to rent I know they refund at least some of the money when I return it but I have to have the money to start with!) I did however, pour gas in TBI, CRANK/ RAN for couple seconds. Firing, Ign. all working for it to burn the fuel that was poured in TBI, right? Fuel pump weak or bad, or what is your take on the situation?


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 30, 2014, 3:57 PM

Post #19 of 28 (1385 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Hmmm? You do get all you money back for safe return of those rentals TMK.


You hear it not quite right. Would be better to see it off spec and that it can't hold too. There's still a chance it just doesn't get strong electrical power thru wires and connections too like cheap jumper cable just don't do it kinda thing if you will.
Doing some math, you need to drive 40 miles just to rent a tester then return it another 40 miles and don't have the cash. They should take a credit card but you have to have a valid one and it would hold that $$ on it.


I'm not sure if you can put your hands up to wires right at access on tank without taking is down at least some to check wiring right there but would prepare for a new fuel pump. I'll let you price that out but whole units of OE quality do have a much better track record of lasting.


At least spray the tank straps and things you know you would have to take apart now in hopes they will not break if rusted even a little they car be fussy and take up time and more parts just dropping a tank for any reason.


Still scratching my head why a plain worn out pump would be so sensitive to bumps? Not sure about why on that?


T



lesgohuntn
User

Dec 30, 2014, 8:15 PM

Post #20 of 28 (1376 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

I don't have any credit cards... Too easy to get in trouble with them (some reason they want you to pay back that money! LOL)



I'm like you, I can't see how a worn out pump would be so sensitive to bumps. The pump that is on it is not very old, although I realize sometimes replacements may not last long.


As for the wires, I can see them, but they are in a tight space. When I try to reach them I can't see what I'm doing because my hand is in the way.

I just remembered, I already have a new pump and strainer bought several months ago. I didn't put it on because something I did at the time, made me believe it wasn't the problem. (It has been a dreaded task I'm afraid I'm going to have to do before this is over) Would you drop the tank, or unbolt and raise front of bed? Seen it done both ways, I just haven't ever put one on myself.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 31, 2014, 12:41 AM

Post #21 of 28 (1370 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

"Raise bed or drop tank thing"


I'm in a rust belt so a 1993 would bust all the mounts and still fight with the tank, filler neck and evap lines and more. Dropping tank would be the way here not if you are unrusty and have help to lift whole bed off or tilt without harm and tools to do it. Your call on that totally.


I'm still caught with why intermittent and bumps? Makes me think you could just whack places with a heavy rubber hammer and cause or cure the problem at will and find it's back to wiring and ground just losing it to carry enough power/amps to do the trick. All over again that testing with proper electrical tests both now while it's happening and when not compared would take out the risk of being all wrong with diagnosis. A new pump might work only because you disconnected its wiring and reconnected it that I've mentioned already. This is no fun. You really might not be sure if this is going to play cat and mouse with you. Yup, room here for even totally checked out to be wrong on exactly what and where. Stuff of the sort when in biz really doesn't please anyone when wrong - trust me!


With this history and your observations if pushed I'd ask to drive the thing for a day or two with all sorts of test things in view to watch while it happens - impossible to do for most or even shops unwilling to go that far for you money or not,


T



lesgohuntn
User

Sep 25, 2015, 8:56 PM

Post #22 of 28 (1178 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Long time since I last posted. I admit, I gave up on the old truck for awhile. I recently started trying to diagnose again.
Turns out, fuel pump was weak. I replaced with pump I already had on hand. I had checked the ground, was good, but I cleaned and applied elect. grease, as was suggested. Running again, but still... shut door, engine died.
I discovered I hit the steering wheel... dies. Slap dash... dies. shut hood... dies. I returned to dash and started bumping in diff. locations, and the closer I got to glove box, the easier to get reaction (engine dies). I reached under glove box and moved wire bundle to ECM... died. Repeated... same. Repeated... engine idle increased. I tried the "wiggle test" before in the same manner, months ago, (as was suggested) and got no reaction... this time reaction every time bundle was moved. As it got dark tonight, I had moved the wires around several times... slammed doors, hood, bumped dash, wiggled wires... I finally got to turn the truck off with the switch!!!
As soon as I get the chance, the glove box once again, is coming out, I'm going to discharge the static from body, and check connections, again. Wish me luck, but I think the problem may be diagnosed.
Thank you all so much, and I will repost when I'm positive this is finally the fix, or not.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Sep 26, 2015, 12:02 AM

Post #23 of 28 (1171 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Still here, quite the time and a read on this but trying from this end.


OK! Seems you've found this bundle of wires that will cause it to act up - YES! That's your area to pay total attention to.


In all this you've said bumping dash, steering wheel, slamming doors (don't do that BTW) aggravates/causes the problem. Now lost as to what totally grounds the dash as a whole the most? I think it relies on side bolts such that it can totally pivot down or lay down on the front seat(s) if you will? That would be quite rare to lose ground IMO. I'd add a ground strap anyway dash metal to body metal and make real sure battery or engine block to body is also well grounded. I think it's main (several around) ground strap is under the hood, passenger's side you'll see strap from frame to body down by starter motor.
OMG - What do you mean getting static out of the body? Yes, it is and was a concern or just annoying to get a slight shock from metal when getting out of a vehicle and blamed for assorted things going funky since the invention of the light bulb!
It's real but never hear of it and almost certainly NOT your issue and if it does shock you with static say so and can find out why as no vehicle this NEW has done that to me personally and they did from the 50s and 60s! Yikes - getting old.
!!!! Just looked, they still sell them new. Pic below if shows now can only be and old joke or if a vehicle's body really held some static charge something is wrong somewhere if ongoing.

Not joking. This problem has gone on for ages up to a new engine you mentioned over an ice storm? What happened even that long ago now? Hit by lightening? Not joking - if that is in this history you might not know it?


It does happen to ships and they need to be "degaussed." Just Googled this and the problem still exists and is more for electronic devices to fix or destroy them but is known to cause erratic electrical behaviors. Vehicles are full of such devices including this and could interfere with it making proper spark. Why it didn't fry something and make itself clear IDK.
That is spelled correctly "DEGAUSSED" and I'll let you search out solutions and testing if this is the problem. I've never heard of or believe such thing would or could be long term or intermittent for a motor vehicle? That doesn't mean it isn't or couldn't be the problem. There actually are machines/devices to fix this for electronics!


Tom
(edited in more on subject)
This is real!
https://en.wikipedia.org/wiki/Degaussing
Apparently happens to be a magnetic charge in metal that can even harm or destroy assorted electronics even now!



(This post was edited by Tom Greenleaf on Sep 26, 2015, 12:11 AM)


lesgohuntn
User

Sep 26, 2015, 11:51 AM

Post #24 of 28 (1155 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

OK, I feel really stupid now, but here it is.
I was told early on by "Hammer Time" to pay special attention to ECM while tapping and wiggling wires as a potential problem, and I did, at least I thought. Turns out, on my ECM, there was a indentation where the harness clips on to ECM that I thought (and obviously the last Chevrolet dealership mechanic) that was where it was suppose to lock the harness on, was a flaw in the plastic. My ECM wasn't plugged all the way in, and yes I did over look that before and this morning as well. It was clipped on, but not on the lock tab it was suppose to be on! I was giving up this morning, about to put glove box back together, and decided to look it over one more time... BINGO... on next wiggle it clicked deeper into ECM and locked! Only then did I see what was happening.
I checked the codes on the OBD, and the only code it flashed was 12, which as you probably know, just means OBD is working. While doing all the tracking wires and trying to find the problem, before, I got several different codes, as I know why now.
Do I feel dumb... YES! But am I happy that problem is now solved... SURE AM!
The static thing was about something I read in a Haynes manual to discharge static from hands by touching metal on the body of truck before plugging or unplugging ECM, as static could damage the unit. Just didn't want to take any chances in frying the unit or something. I didn't think it was that much of an issue, but aired on the side of caution since, I'm sure the Haynes folks have had much more experience in that area than I have.
And slamming the door thing, the hinges on drivers door are letting door sag, and I have to shut door hard to latch it shut. I wasn't implying that I just slam it to get a reaction. Hinges just another project that hasn't got the attention needed yet. Soon to come, I hope, as well as the steering gear that decided to spray my boots with power steering fluid while attempting to diagnose the wiring issue. It blew a seal. I guess that's what I get for giving up, and letting it set too long.


Any way, again, I want to thank all who helped me. If not for all of you, I don't think I would have figured this head ache out! Ya'll are doing a great thing for folks like me, who knows some basics, but lack the experience needed to solve these kind of issues. If ever I said anything to offend any of you, I sincerely apologize. I went through many days of bad moods with this issue, but that's still no excuse.
Thanks again.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Sep 26, 2015, 12:28 PM

Post #25 of 28 (1151 views)
Re: 93 Chevy Z71 heitates, now dies when door is shut Sign In

Great! Clearly worried your truck was magnetically possessed or something totally out of any norms.


Hey - Door hinges on this: Take a look now and do soon. You should notice that the whole hinge is welded to both door and body with a pin with bronze bushing you can replace but not adjust the door UP to close better.


Bring that up in another thread if lots of trouble for some tricks that may work if new pins alone are a problem - cheap and easy with a helper to hold the door pretty much,


T







First page Previous page 1 2 Next page Last page  View All Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap