I'll certainly agree with that, especially since it doesn't do diddly-squat for gas mileage.

 

I don't know what happened. The TPS fixed the issue for a few days and then the symptoms started up again. Either the new TPS is defective or there is another issue. My questions are: Is it likely that the new TPS was new and bad or is there another issue? If there is a different issue, why did replacing the TPS make the symptoms go away for a few days?

 

If replacing the TPS solved the issue only for a few days, then there are a few possibilities.

Here are some.

The TPS was not the issue, the TPS connector, or its wiring to the connector is/was.

Did you test the TPS? They are fed 5 volts and a variable resistor sends voltage back to the engine computer which determines the throttle position and controls the fuel injectors.

The TPS is near other sensors. Touching their wiring allowed an intermittent contact to be more reliable for a while before resorting to it's previous evil ways.

I've been on a bit of a connector bent lately. I found the connectors to my Map, 02 CTS and TPS sensors to be extremely oxidized.

Caig Deoxit Products can clean connectors like no other product can even hope for.

See if wiggling connectors with the engine running induce the issue to return.

Get some Deoxit, disconnect the battery, and goto town on all the sensor connections you can find. Precision q tips and mini bottle brushes can really restore electrical connectivity.

My connectors were always bathed in dielectric grease. Most connectors oxidized despite this 'protection' and the connectors which apparently got hot formed a flakey translucent substance in the connector and compromised conductivity to some degree.

The oxidation I recently cleaned out of my glass fuse holders jaws was rather resistant to removal.

Sure the new TPS could have failed, but it is more likely that the simple act of removing and replacing the connector allowed connectivity for a few days.

Try it again to test. and get a strong light on the pins and sockets within the connector to inspect/

 

1st, Have you pulled any DTCs (engine codes)?

landyacht makes a strong case on a poor/intermittent TPS connection, considering it how it was resolved for a short period.

Test the TPS and connections...
Similar symptoms, test the MAP sensor


PCM/ECU; ignition coil and/or lead wire; distributor; main ground, etc could all be flaky as well.

 

This is all pretty typical symptom of bad Dodge connectors and bad sensors. Dodge/chrysler uses low quality wire and connectors so this is actually quite common. You'll need a high end ODBCII reader to sort through them and even with that you'll probably get a number of false positives and dead ends.

My 2000 runs great and I've been very lucky but: I solder everything and leave nothing to chance. Quick disconnects are just an failure waiting to happen IMO. Then again I repair marine electronics so I expect everything to fail if isn't silicone or epoxy sealed.

If you are in the south Kentucky area feel free to PM me and bring your van out to the house. I'll be happy to take a look at it, no charge naturally. An electronics engineer and computer programmer by trade I can usually sort these issues out. Worst case scenerio: you may need a replacement PCM but you are welcome to camp here for free until it gets sorted out.

Try the Deoxit first, then report back pls.

 

Thanks for the offer, unfortunately I'm in Florida and that wouldn't be an option for me. Awesome that you would make that offer to an unknown van owner, though. Anyway, I'm still having issues. I tried cleaning the sensor connections as someone suggested, but that didn't help.

I still drive the van almost daily and am having to deal with the almost stalling, hesitating and trans jerking day-to-day. Until I'm ready to hook up the diagnostic tool to the computer, I'll never know what the problem is. I keep putting it off since the van is still running, but I really need to get this taken care of soon.

I really appreciate you guys taking the time to read and suggest things that may help my situation.

 

How did you clean the sensor connections? After flushing the dielectric grease, did you get a strong light in there, perhaps a magnifying glass and have a close look?

The issue can also be the engine computer connector, and the wires immediately next to the connectors. Techs love to pierce the wire insulation here to diagnose issues, and do not bother smearing some rtv into the hole. The wire soon corrodes and sooner rather than later the wires ability to carry current is compromised and leads to weird intermittent symptoms.

Frequent ECM connector removal and reinsertion can also break the solder connections on the circuit board, another known issue with Chrysler's. Just the weight of the wires hanging off the engine computer can also break the solder connections on the circuit board, given time and vibration and heat cycling.

With the engine running, try wiggling the wires and connector bases at the engine computer. If any stuttering or stalling occurs, Bingo.

Praise for the efficacy of Caig Deoxit products cannot be stated loudly enough. No other electronics cleaner sold in AP stores can come close. They are good at flushing out old dielectric grease and detruis only. The Oxidation on the connector metal itself is not addressed by any Autoparts store electronics cleaner, and reliance on them to restore electrical conductivity, and then ruling out the connectors as culprits is Akin to shooting oneself in the foot.

 

Apologies for not answering your questions out right, but after replacing the sensor, can it possibly be that I need to disconnect the battery and reset the computer so that it could learn the new engine behavior all over again? Can the computer still be stuck in the old TPS routines and just need to be reset? I think this is probably not likely, but I'm not an expert. I guess there's only one way to find out.

 

Can't hurt to disconnect the battery to reset the pcm.

My '89 tends to run a bit crusty the first warm up cycle after a reset, If the computer is reset when the engine is still warm, it runs somewhat crusty until after the the next cold start when the throttle response is much improved thereafter.

Am not sure on other year vans.

 

For those who were wondering, no, resetting the computer did not solve the issue, as expected. That would have been too easy. Anyway, I'll head over to the auto parts store tomorrow and see if they can hook up the diagnostic tool and clue me in on the issue. I'll post back when I know.