1989 Ford E-150 5.0 EFI cargo. Water temp & oil pressur


	Auto Repair Home	SEARCH POSTS	WHO'S ONLINE	LOG IN

Automotive Repair

Car Troubleshooting Topics
  Car Troubleshooting
  Engine Troubleshooting
  Engine Fault Codes
  Electrical and Wiring
  Transmission Problems

Car Repair Topics
  Car Making Noises
  Car Stereo Repair
  Heating or AC Issues
  Motorcycles and ATVs
  Tricks of the Trade
  Truck Repair Advice

Site Options:
  Login
  Sign up here!

Latest Forum Post

2011 Dodge Nitro OBD scanner seems to drain battery in 10-20 minutes

When I bought this car in summer 2023, a...

Grounding Cable, 2017 Jeep Renegade Trailhawk

The Cable that connects my negative batt...

Rough Idle (Found new thing)

Hi everyone. First of all sorry for bad ...

equipment

hey yall. im a first year engineering st...

HELP

I have a 1956 1/2 ton panel truck, 69 35...

Howdy

    Just wanted to s...

ABS/Tractiob/Brake Lights on But No DTCs

Hello all, Recently while driving m...

Chevy strut replacement

I'm trying to get a sensor of some kind ...

2020 suburban new transmission and issues after install

recently had the transmission fail at 11...

Caliper piston post cleaning won't screw in

Hello, 2013 Hyundai Elantra limited (ma...

1989 Ford E-150 5.0 EFI cargo. Water temp & oil pressure (only) peg to high side when a/c switch turned on.

Sign up here!

Email This Post

Auto Repair Home>> Automotive Repair>> Automotive Wiring and Electrical

rhoden44
New User

Apr 16, 2015, 7:32 AM

Post #1 of 4 (1081 views)

1989 Ford E-150 5.0 EFI cargo. Water temp & oil pressure (only) peg to high side when a/c switch turned on.	Sign In

Bought van new n 1989. This problem has been since new.
Did not connect the two until my a/c went out and I turned on the
Fan for air (not a/c). The "short usually doesn't last long, and its not all the time. I have been troubleshooting but can't seem to find any connection
Between the gauge circuit and the a/c circuit. Have ask several mechanics and no one seems to know. Any ideas?
Thanks for your help.

Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Apr 16, 2015, 9:34 AM

Post #2 of 4 (1065 views)

Re: 1989 Ford E-150 5.0 EFI cargo. Water temp & oil pressure (only) peg to high side when a/c switch turned on.	Sign In

Ideas and just looked at two in cars not the truck 5.0 which is asymmetrically opposite from cars.

First - If this did this when brand new why the heck have you put up with this so long and or was it fixed when new for a while?
How long and what went wrong with A/C if known? Still thinking...........

I think you should try if A/C is not going to be fixed unplugging it at compressor and tie the plug safely out of harm's way and see it that stops the problem. A failed clutch coil on compressor could be adding ground and would take a short in wires touching someplace.

Ford for the year in general liked to run a lot of wires together inside plastic protection and wrapped with electrical tape from new. Wires can cross down and under on the cars or along firewall but since a van can't say and if inside those all wrapped up not sure how routed and since did it new (is that correct?) wires were bumped hard just putting it together new!

Many also not long after new would not engage fan (if auto fan controls or ATC equipped) the detents where contacts are made at control head needed a wiggle to get going not crossing up like this but a problem spot.

Hey - if this is messing up techs with it right at hand it's the wildest of guesses from here and intermittent from new even harder. My WAG and never took one apart on any Ford yet is where wiring goes thru usually a block of wires from inside cabin to engine area is the problem spot originally.

Can't compete (it's not a competitive game with those right at it. Chase wires involved or whatever it takes. If fault in control head IDK if a new one would be available at all or even refurbished ones.

Another thought/place: Does "doghouse" get too close to wiring or show more looking thru there? I plain forget on the vans how much more you see from there on back of engine for wiring?

Was tough then and is now,

T

rhoden44
New User

Apr 16, 2015, 1:49 PM

Post #3 of 4 (1054 views)

Re: 1989 Ford E-150 5.0 EFI cargo. Water temp & oil pressure (only) peg to high side when a/c switch turned on.	Sign In

Many thanks.
I recently noticed, up until now I have constantly had either the air or
heat on. I live in Florida. Bought the van in Indy going to work in mich.
Now I'm retired and fixing it up.
I wil try your suggestions and get back.
Again thanks.

Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Apr 16, 2015, 3:21 PM

Post #4 of 4 (1051 views)

Re: 1989 Ford E-150 5.0 EFI cargo. Water temp & oil pressure (only) peg to high side when a/c switch turned on.	Sign In

Good luck - said this could be a hunt down. Long read for you , sorry, do wiggle test even the selector and nudge towards the next selection out of the detent. About all ATC (climate controlled ones anyway) you lost auto fan if you didn't nudge heat just a smidge away from exact.

For this doesn't matter much but I'm in MA both super cold and super hot (short time never all day long) some wet, humid and top couple places for rust but that shouldn't be this at all.

Most vehicles the wiring goes into a pack of wires to come out elsewhere so could be a pest. A/C as said. Start disconnecting at compressor and back to the switch at the black or aluminum can is an accumulator. TMK that power comes from a relay could be on other side in engine compartment if OE I think is black with a gray skirt not marked but you should see a black wire w yellow stripe from the right one same as seen at the switch mentioned,

T

Email This Post

Search for (options) Privacy Sitemap