'96 T&C issues

[yukong]

Greetings: First post. Have been a looker/lurker for some time though. I have a real issue with my T&C.

It is a 1996, T&C, 3.8 liter. 150,000 miles. Transmission rebuilt at about 130,00.

A few months ago, I started developing an intermittent issue where the van would be difficult to start. It would turn over but not hit. Like it was getting no gas. It would then display a P0340 (Camshaft Position sensor) code. Every now and then it would die. I replaced the camshaft position sensor and it seemed OK for a couple of days, then it would start again. Still with the P0340 code. chrysler gave me a new camshaft position sensor and I put that in. It still didn't help. It might go for a few days without an issue, then it might die several times in a day. It has been doing OK, for the past few days until yesterday. I was driving it home after being out for a few hours, and it started to cut out and then died. It started up, but died again. Then when I got it started, it ran real rough, sputtering like it wasn't getting gas. Then it smoothed out, but when I stopped, it was idling very fast, (about 2500 rpm). I had to stop and get gas. when I restarted it, it still idled fast. When I started to drive home, it would bog down when I gave it gas, but would run smooth, but with high idle without gas. I got almost home and it died again. After that, I could not get it to stay running. It will start, but just sputter and idle rough, then die. I checked the codes, and got the following:

1. P0340 - Camshaft Position Sensor.
2. P0122 - Throttle Pedal Position sensor A Circuit low input
3. P1294 - Target idle not reached.
4. P01491 - Radiator fan relay control circuit.
5. P0123 - Throttle Pedal position sensor A High output
6. P0188 - Engine coolant temperature circuit high input.
7. P0106 - Manifold Absolute Pressure/BARO sensor range performance.

Is all this telling me that the PCM has finally crapped out and that it has been the PCM the whole time?

If so, can I put a used PCM in the car and have it run?

Thanks for your time and help. I really need to get this car running if possible. It is in great shape otherwise. Both interior and exterior and we love this van. Thanks.

[plymouthsrock]

Check the relevant wiring to the sensors (5V and ground) and PCM grounds, especially if there is a common point to the sensors that are throwing codes.

[yukong]

Thanks for the reply.

Additional info. Went out today to try and start it, and it will not even attempt to start. The starter will crank, but the engine will not fire at all. Like it is completely out of gas or something. No hint of even starting.

As to your suggestion, I have never done something like that. Where would it be best to begin, and what should I be looking for?

[plymouthsrock]

This might be beyond your scope (it is for most professionals as well), but you could try shaking the engine wiring harness while cranking to see if something changes. Then you know you're on the right track. I had rodents eat through my harness, and the van would not run. If you want to dig deeper, get a repair manual that has wiring diagrams in it.

[yukong]

Interesting update. Last night I was poking around trying to find a problem. Since this all started with a camshaft position sensor code, and that has been consistent throughout I thought I would run some voltage tests on the camshaft position sensor. After quite some time I determined that it was working properly. It was getting the right voltage, and when I manually turned the crankshaft, the voltage on the sensor would respond properly. So, I then thought about checking to see if I was getting a spark. But in the process, I just wiggled on the two connectors at the PCM. I then get in the car to turn it over and it wouldn't do anything. No crank at all. I got out, unplugged both PCM connectors, and then plugged them back in. I tried to crank the car again (remember before now, it would crank and crank but not start) and it started right up. Well, since the car was at my daughter's house, I drove it home. It ran fine, but I did keep getting the p0123, P1491 and p0118 codes. When I got home, I turned it off, and then tried to start it again. It would just crank and crank, but no start. i then unplugged the PCM again, and then plugged it back in and it started fine several times. Still getting those codes though.

What do you think? Connectors, wires, PCM?

[Alphabravo]

Sounds like you have the female connectors at the PCM harness that have widened and do not make good contact. I've read in this forum somewhere that this can happen. Try using a pick tool to push the tabs tight.

Good luck.

[plymouthsrock]

Sounds like you're on the right track!

[yukong]

Originally Posted by Alphabravo

Sounds like you have the female connectors at the PCM harness that have widened and do not make good contact. I've read in this forum somewhere that this can happen. Try using a pick tool to push the tabs tight.

Good luck.

Hate to sound dense, but when you say pick tool, what do you mean? And do you mean the tabs inside the plastic holes?

[plymouthsrock]

The goal there is to compress the individual metal (female) connectors so they fit tighter over the PCM pins.

[GNXdreamin]

Wow, is this a blast from the past! I had the same issues with my '96 T&C. I figured out if i put another pcm in it, it would run GREAT for anywhere from 2 days, to about 2 1/2 weeks. I was really thinking it was an electrical issue, but in the end, turns out i was wrong. When you get a new computer, or put in a used computer (pcm), the engine starts up fine, because there are pre-determined variables that are stored in the computer. Once your car goes through a number of key on, key off cycles, as well as runtime, it "learns" based upon variables, or information that is sent from your various sensors, such as cam and crank sensors, etc. Once the new variables are introduced, if you have a sensor that is out of range for whatever reason, then it may not run right. My problem turned out being a cracked flywheel. The flywheel was cracked in a complete circle, all the way around, just past the flywheel to crankshaft mounting bolts. Your crankshaft position sensor picks up a reference signal from marks, or notches that are cut out of the flywheel. Since it was broken in a circle, the entire flywheel spun around, making the reference marks shift from where they should be. My van started by being hard to start, then it would run like you know what, almost like it was starved for fuel, then it would get crazy and just shut off while driving down the road. Ended up to the point where it would crank, but not start. So, all this being said, crawl underneath your van, and at the bottom of the bellhousing on your transmission, there's a small inspection plate that is easily removable. Remove this, and use a flashlight to inspect your flywheel......Good luck!! I wound up replacing my flywheel, flywheel mounting bolts, rear main seal housing, rear main seal housing gasket, and rear main seal. Luckily, the damage didn't get into the crankshaft...your situation sounds VERY similar to mine, so thought i'd share my experience. If it is damaged, you'll need to drop your transmission to get the job done. GOOD LUCK!!

[yukong]

Update:

I tried to use a pick tool to tighten the female connectors, but my pick tool was too weak and just bent. Anyway, I used contact cleaner on all the contacts and let them dry out. I then put plugged the PCM back up and made sure the plugs were seated good. After that, the van has run fine. Occasionally I would get a random code, but eventually it would clear. All in all, it was fine. Well, this past Sunday, when we were about to leave church, the van died. I tried and tried to get it to start, but it would just crank. So, I got out and unplugged the top PCM plug (as that was all I could reach, dressed in a suit and whatnot). Got back in, and the van started right up. I did have some codes, but it ran. Drove to lunch. Coming out of the restaurant, the car wouldn't start again. Repeated the plugging/unplugging and it started and ran fine. Did get the following codes. P0340/P1492/P0138/P0118. At home, I pulled the PCM, and used contact cleaner again, and cleaned the contacts on the PCM and on the connectors. Let them dry out, and now all seems fine again. I did notice that it appears that I am getting water in the engine compartment from rain as when I removed the battery, there was water standing under the battery. It didn't come from the battery though. And there was dust/dirt between the outside of the PCM connector housing, where the connectors slide down on the PCM. Could this be an issue?

Any thoughts would be appreciated.

[RIP]

Dielectric grease on the connections can help ward off the H20. Available at any parts store.

[yukong]

Well, that didn't help after all. It was doing fine. But then it started acting up again. It died, and wouldn't start. I unplugged/plugged the top PCM connector and it didn't help. Then I unplugged/plugged the bottom PCM connector and the car started right up. I had to do it again later in the evening, but it seems the issue is related to the bottom plug. Any ideas?

[mishalah]

These models are notorious for having the main wiring harness get corroded from battery acid because the battery sits right above the harness connectors. I had my connectors replaced and rewired about 6-8 years ago and it cured any of the gremlins that were showing up. It's a tedious job, but the alternative is to replace the entire harness at $1000+.