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Rough Idle and Burning Smell


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nrgins
User

Jun 7, 2015, 2:54 PM

Post #1 of 22 (1672 views)
Rough Idle and Burning Smell Sign In

Was driving home just now when my car (2003 Dodge Caravan SE) started acting strange. Stopped at a light, it started going back and forth a little, like the transmission was stopping and starting. As I drove I noticed that it kept doing that when I had the accelerator pressed slightly. When I pressed the accelerator more fully, the problem seemed to mostly (not completely) go away.

When I got home (after driving like that for about 2 miles), it seemed worse. When I stopped the car and had it idling in Park, the engine died. I was able to restart the engine, but it seemed like it was having trouble staying on (though it did for a minute or two until I turned it off).

When I got out of the car, I noticed a bad smell coming from the engine, like burning. Also noticed a loud sound, like knocking.

My first thought was that I didn't have any oil. So I checked the oil and the transmission fluid. Both were fine.

After about an hour I restarted the car, and it wasn't doing it anymore. Maybe because the car had cooled down?

Any ideas on what this might be or what else I can check?

Thanks!

Neil


Tom Greenleaf
Ultimate Carjunky / Moderator
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Jun 7, 2015, 4:38 PM

Post #2 of 22 (1662 views)
Re: Rough Idle and Burning Smell Sign In

Sounds like you've overheated. Any warnings on dash WHEN this happened or gauge way up there?


Now time to know coolant is full in radiator not just the recovery tank and that fan does come on when needed for the radiator. More possible troubles but first know that much. Don't let it overheat in even testing things out,


T



nrgins
User

Jun 7, 2015, 4:59 PM

Post #3 of 22 (1656 views)
Re: Rough Idle and Burning Smell Sign In

When I was driving, I looked at the temp gauge, mainly because I wanted to make sure that it was hot enough to check the transmission fluid. The temperature gauge was exactly where it always is, just a little below the halfway point. So I don't think that was it. Thanks for the thought, though. Appreciate it!


Tom Greenleaf
Ultimate Carjunky / Moderator
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Jun 7, 2015, 5:28 PM

Post #4 of 22 (1654 views)
Re: Rough Idle and Burning Smell Sign In

Are you convinced the gauge works? This smacks of an overheat all over the place. Smell/knocks, rough idle possible and stalling. Then later will not do it when cool again.


Hard to know if coolant level is in fact full on many vehicles. Clue to overheat is heater DOESN'T work believe it or not. Boiling coolant or lack of coolant will not transfer heat for heater or your radiator. Sensor that tells you on dash might no longer be in coolant but rather vapor and slow to respond?


So you didn't answer my question or definitely find out if coolant is full yet. That's first on the list right now,


T



nrgins
User

Jun 7, 2015, 5:39 PM

Post #5 of 22 (1648 views)
Re: Rough Idle and Burning Smell Sign In

The gauge always seemed to work fine. I suppose it's possible that it stops at a certain point and doesn't go higher.

I'll check the coolant level and let you know.


nrgins
User

Jun 7, 2015, 6:00 PM

Post #6 of 22 (1646 views)
Re: Rough Idle and Burning Smell Sign In

Well, I went out and checked where you pour the coolant in. It was a long plastic tube and went down to a squarish plastic reservoir.

Looking through the side of the plastic reservoir, I could see at the "Max" line there was definitely no coolant there. At the "Min" line I couldn't tell. The container was darker there. So I couldn't tell if the darkness was from coolant being there, or just discoloration of the container.

I tried moving the container around to see if I saw any swishing of liquid. I saw none. So I'm guessing it's completely empty.

(I had my oil changed a few weeks ago, and they were supposed to check all fluids. Guess they didn't.)

So now I'm trying to figure out which coolant to buy. I don't have the user's manual for my 2003 Caravan SE. I found a 2004 Caravan manual online, and it said to use:

"Mopart Antifreeze/Coolant 5 Year/100,000 Mile Formula HOAT (Hybrid Organic Additive Technology)"

So I guess that would be the one to use? I'm headed to the store now. Let me know if you know which one to use. I'll check for replies on my phone.

Thanks!!


nrgins
User

Jun 7, 2015, 6:54 PM

Post #7 of 22 (1643 views)
Re: Rough Idle and Burning Smell Sign In

OK, just got back from AutoZone.

First, before I went to AutoZone I realized that I had been checking the reserve tank, not the radiator. So I took the cap off the radiator and checked it. It was full. But reserve tank seemed empty.

So I went to AutoZone and they checked the code of my Check Engine light. The code was P0108: "MAP (Man. absolute pressure)/BARO or MAF (Mass Air Flow)/VAF (Vane Air Flow) sensor condition.

He said that cleaning the Mass Air Flow sensor would probably clear it up.

Was interesting: when I drove to the place (about 3 miles from my house) with the engine cold, the car drove fine. As I approached AutoZone, the car started to buckle a little, but not too bad.

Then, after being there about 10 minutes and driving home, it started acting real bad. Would buckle as I slowed down. Had to put it in neutral when I approached a stop sign so I could give it gas.

Then, by the time I got to my house, it was just buckling whether I was going slow or fast. It was like riding a bronco. I barely was able to make it back home it was buckling so bad.


Hammer Time
Ultimate Carjunky / Moderator
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Jun 8, 2015, 2:11 AM

Post #8 of 22 (1632 views)
Re: Rough Idle and Burning Smell Sign In

What engine does it have?



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

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
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Jun 8, 2015, 3:04 AM

Post #9 of 22 (1629 views)
Re: Rough Idle and Burning Smell Sign In

Yes - please state which engine.
You shouldn't ever be out of range on coolant. That tank really just catches overfill from expansion and draws it back as it cools. Unseen if overheated it would/could blow out there and not have enough to show in normal areas which is why I asked.


I asked if heater worked - no answer? Now we know it's lost coolant somehow or place and smells so there should be evidence somewhere.


Temp gauge: Asked if it worked and mean does it read cold when cold then move up expectedly? For all I/we know it's stuck at one spot seeming normal?
Fan for radiator must work. If not warm enough it may not need to. If A/C equipped and it works it would put fan(s) on with that request.


It's nice of places like Autozone to do code readings. Know these places are parts outlets not there to diagnose your car. They should be able to look up correct antifreeze to add or use for a change and so on.


Still need to know why and where it needs it and if that the source of noise, roughness too if leaking on certain items and whole problem isn't going to heal itself without finding source problems and fix what that caused. Is the odor antifreeze itself or something else not known yet,


T



nrgins
User

Jun 8, 2015, 6:17 AM

Post #10 of 22 (1618 views)
Re: Rough Idle and Burning Smell Sign In


In Reply To
What engine does it have?


3.3L


nrgins
User

Jun 8, 2015, 6:38 AM

Post #11 of 22 (1615 views)
Re: Rough Idle and Burning Smell Sign In


Quote
I asked if heater worked - no answer?


I didn't catch where you were asking if heater worked. But, yes, heater works fine. Tested it yesterday when I turned on the engine to see if coolant dropped in radiator (it didn't).


Quote
Temp gauge: Asked if it worked and mean does it read cold when cold then move up expectedly?


Yes, it works fine. At cold when cold, and then moves up and stops at the exact spot it should stop. As noted yesterday, if the car is overheating, then the temperature gauge must be stuck at a certain point, because it doesn't go higher than it should. But up to that point, it works fine.


Quote
Now we know it's lost coolant somehow or place and smells so there should be evidence somewhere.


The reserve tank was well below the "Max" line, as noted yesterday, but the radiator itself was full.


Quote
Fan for radiator must work. If not warm enough it may not need to. If A/C equipped and it works it would put fan(s) on with that request.


Sorry, not following what you're saying here. Is there something you'd like me to test? Are you saying to turn the A/C on and see if the radiator fan comes on?


Quote
Still need to know why and where it needs it and if that the source of noise, roughness too if leaking on certain items and whole problem isn't going to heal itself without finding source problems and fix what that caused. Is the odor antifreeze itself or something else not known yet,


As for smell, yesterday when I drove it back from AutoZone and the car's problem was worse than it had been before (like a "bucking bronco") I checked the smell and it wasn't as bad as it had been the previous day. The engine was very hot and there was a slight smell coming from it. But didn't notice anything really strong.

So maybe something had been on the engine the previous day? Don't really notice a strong smell now.

Also, as for the noise, I was listening to the engine yesterday after the "bucking bronco" thing, and didn't hear the clanking sound I thought I had heard the previous day. Maybe I imagined it? I don't know. I thought I had heard a noise. But now I'm not sure anymore. Sorry about that!

But the rough ride (first nothing; then at idle and low speeds; then at any speed -- getting worse as the car warms up) is definite. I'm definitely not imagining that! LOL

Thanks for all your assistance. It's appreciated!

Neil


Tom Greenleaf
Ultimate Carjunky / Moderator
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Jun 8, 2015, 7:07 AM

Post #12 of 22 (1613 views)
Re: Rough Idle and Burning Smell Sign In

OK, I take it the heater works fine now and that means at least there's some coolant or enough in the system to not be the total up front issue IMO.


Fans: One or more for cars. A/C forces fan on or at least one if two. If A/C doesn't work at all left unfixed (fine for many) it might not trigger it but high enough temps would. Some almost never come on while you wait.


Try this if nothing else. With a small stick, engine off, keys out, see if the fan blades even turn. Might find it/they are locked tight?


Info on coolant level: Tank catches expanded coolant when warm there's more volume and cold less. The idea is don't waste it and keep actual engine and radiator totally full at all times and air out.


Since that is the one found low it probably got on something it shouldn't have now old and weak to tolerate it. Incorrect info can get sent along and self adjusted engine operating controls all confused - runs lousy or not at all.


This could be multiple things and you may save a lot by getting this professionally diagnosed only with expected costs. Then can decide if you wish to do all or part of the work and know if simple or complicated. Some things will take more in tools and equipment for a one time fix that you'd never recover costs. So far we aren't sure.


Other on the smell/odor: It's plain warmer out. Oils and dirts that build up may have just dripped down onto something hot once and quit it or be a sign of something that is in trouble. There has to be a reason for coolant being low unless you really can't know it even was all along,


T



Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jun 8, 2015, 8:57 AM

Post #13 of 22 (1601 views)
Re: Rough Idle and Burning Smell Sign In

As for your Mass Air flow sensor cleaning that Autozone recommended, it doesn't even have a MAF so don't take any advice from the parts salesman trying to be mechanics.



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

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.



nrgins
User

Jun 8, 2015, 10:07 AM

Post #14 of 22 (1594 views)
Re: Rough Idle and Burning Smell Sign In

OK, I just got back from the repair place (City Garage). Guy spent an hour diagnosing it and that the MAP sensor readings are all over the place, and the MAP sensor probably needs to be replaced. They're ordering the part and are going to install it to see if it resolves the problem.

Cost:
MAP Sensor: $201
Installation: $44
Diagnostic fee: $119
Shop fee & tax: $37
TOTAL: $392

The thing about it is, I looked online, and MAP Sensors for a 2003 Dodge Caravan is about $30-$40. And they're charging me $201 for it??

Also, don't shops normally waive the diagnostic fee if you have the repair done there? But they're charging me $119 diagnostic fee ON TOP OF the repair costs. Is that normal?

UPDATE: called the place and asked them why they're charging me $200 for a part that AutoZone is selling for $50. They said they're using the original Dodge (Mopart) part, and that's why it's more expensive. They said that 3rd party MAP Sensors usually won't work; or if they do work, they'll go out in a short amount of time.

So that's their rationale. Any thoughts on what they said?

Thanks!

UPDATE 2: Called another place to get a price. They wanted $140 for the part and $53 for labor. But they said it was an after-market part.

So one place wanted $201 for an OEM part, the other $140 for an after-market part. Both seem high.


(This post was edited by nrgins on Jun 8, 2015, 10:37 AM)


Tom Greenleaf
Ultimate Carjunky / Moderator
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Jun 8, 2015, 12:09 PM

Post #15 of 22 (1584 views)
Re: Rough Idle and Burning Smell Sign In

1. Usually diagnostics go towards the bill but up to the place's policy.


Big IDK about parts prices all over the place. First thing is yes they mark up the part they diagnosed and should take responsibility for it AND that it was in fact the issue. This is saving your car if correct BTW from tons more troubles.


If you had an up front agreement to use YOUR parts all bets off on if it works properly and dunno anyone who would warranty YOUR parts.


Ask about it and that your objective is the problem solved and be on your way without this problem.


You probably can't imagine how costly it is to own equipment, tools, training plus usually insane costs for the place to do biz!


Old rule of thumb with quality if this is. "You'll forget the price when it's all fine again but will remember poor quality and workmanship forever!"


It could still go wrong and that's when the caliber of the place should shine.


I can't know exact pricing for each area myself which hides all the cost of being able to do it at all,


T



nrgins
User

Jun 8, 2015, 12:44 PM

Post #16 of 22 (1579 views)
Re: Rough Idle and Burning Smell Sign In

Yeah, you're right. Quality is what's most important. This place has the highest rating on Google Reviews in my area (4.8 stars out of 5). So that's good.

Also, they give a 2 year warranty on repairs. Most places give 1 year.

But, just got a call back from the place. They said they found the part at another dealership for $140 instead of $201. I guess after I called them and asked them why they were charging so much, they wanted to lower the price. Don't know if they actually got it at another dealership, or if that's just a line they're giving me. Either way, they lowered the price by $60, so that's good.

But the bad news is they said that they found what caused the MAP Sensor to go out. They said the injector wiring harness (subharness) underneath the intake plenum was completely stripped of casings, that the wires are exposed, and they probably touched each other and shorted out the MAP Sensor.

He said it would be $880 (parts and labor) to replace the wiring harness. I asked if he could just wrap the wires with electrical tape to keep them from shorting out. He said the wires are corroded and a little frayed. I said, well, they might still be good enough to work, and I'd rather just wrap them to keep them from shorting out, instead of spending $900 to replace the wiring harness. He said he would give it a try and see if that gets the check engine light to go off.

A photo of the wiring harness taken by the shop can be viewed here: https://dl.dropboxusercontent.com/u/16018055/wiring%20harness.jpg


nrgins
User

Jun 8, 2015, 1:51 PM

Post #17 of 22 (1572 views)
Re: Rough Idle and Burning Smell Sign In

Just heard back from the place. They said they wrapped up the wires that were exposed, but it didn't make the check engine light go away. They said it's throwing a new code: 1299: Idle Air Flow. Said they need to replace the injector wiring harness (for $880).

I looked it up, and that refers to a vacuum leak. So I called him back and asked him about it, and he said they looked for a vacuum leak, spraying a can of something over the vacuum hoses, but couldn't find a leak.

So I'm wondering what the wiring harness has to do with it? Yes, the wire were exposed (and touching). But why, after they were wrapped, would it be causing an Idle Air Flow code to be thrown?

He said that they didn't see all of the wires, only the part that was visible. So there might be other places where wires are exposed.

I'm thinking, now it's up to $1200 for the repair. And who knows if the wires touching damaged something besides the MAP Sensor?


Tom Greenleaf
Ultimate Carjunky / Moderator
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Jun 8, 2015, 1:59 PM

Post #18 of 22 (1570 views)
Re: Rough Idle and Burning Smell Sign In

Arggh! What was the reason if any given for that happening? I don't have labor times for just that work on top.


I'm asking you now! So if you do all of this is it going to last or just do all this crap again from a cause not known yet or what? Those wires look horrible of course. I'd expect that from like an engine fire or something!
?? So in a way if you ask them to proceed and patch up those wires and this happens again then who takes responsibility.


I'm not liking this problem and the dependability of this and don't happen to know if it's common or not.


It's getting pricey justified for the work or not is it time to think (for your needs) changing out vehicles for another for this vehicle in overall shape or what do you want to do now?


T



nrgins
User

Jun 8, 2015, 2:12 PM

Post #19 of 22 (1565 views)
Re: Rough Idle and Burning Smell Sign In

Apparently this is a common problem when dodge/chryslers get old. I found a post where the guy had the EXACT SAME problem as me, and his wiring harness was melted too. He also looked for and couldn't find a vacuum leak. In the end, he said he wrapped up the wires and it fixed the problem. Here's the post: link deleted .......... not allowed

(I hope I answered your question. If I didn't, then please let me know. Thanks!)


(This post was edited by Hammer Time on Jun 8, 2015, 5:06 PM)


nrgins
User

Jun 8, 2015, 3:28 PM

Post #20 of 22 (1561 views)
Re: Rough Idle and Burning Smell Sign In

I sent the guy at the shop that post I linked to in the last post, since the guy had the same make/model/year car as me and the exact same symptoms and the same code. The post said once he taped up all the exposed wires on the wiring harness, the problem cleared up. So I asked the guy at the shop to do that.

He said to get to more of the wiring harness, he'd have to take some things apart and it would be an hour of labor, which he'd charge me for. I figured it was worth risking having pay for an hour of labor than to spend $900 on a new wiring harness.

So he taped it up, though he said he couldn't get to all of the wiring harness. He said that would've required taking the plenum off. But he said he taped up most of it and that when he tested everything it worked, except that the MAP Sensor was reading 3.8V, and it needed to read at 5V to function correctly.

So he put the new MAP Sensor in, and it read at 5V. Said the car is running smoothly, there is no longer any code, and everything is fine. So that's great.

Thanks for the help!


Tom Greenleaf
Ultimate Carjunky / Moderator
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Jun 8, 2015, 3:43 PM

Post #21 of 22 (1559 views)
Re: Rough Idle and Burning Smell Sign In

It's always your call what to do. I just saw a mess of raw wire and not real thrilled with even the best tape up job and tape. If this tech has done it with whatever methods with good results your call to go that way or not.


Good luck whatever way you decide to go,


T



nrgins
User

Jun 8, 2015, 4:47 PM

Post #22 of 22 (1553 views)
Re: Rough Idle and Burning Smell Sign In

Thanks. Just picked up the car. Running good! They didn't get to the wiring harness underneath the plenum, which worries me a little. But the parts they did fix solved the problem. So, keeping my fingers crossed that the rest of the wiring harness doesn't go out in the future.

Since this seems to be a not-uncommon problem, based on the number of posts I saw about this for Chrysler/Dodge vehicles, I'm guess there was some defect in the wire casing material which makes it more susceptible to melting.

Thanks again for your help!

Neil






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