QuestionQUESTION: Beginning this fall, the engine shudders and stalls when stopping until it warms up. Initially it only did this in fall (not so cold) when the defroster (A/C) was on. Now even with defroster off, it does it until the car warms up. No check engine light (I think, daughter has car out of town and she's had other experiences with the light coming on but hasn't reported it here).
Thanks for any ideas on this and especially for providing such a valuable service to all of us.
ANSWER: Hi Larry,
The best way to get a handle on the cause would be to get a fault code readout using the ignition key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see the mileage change to show 4-digit numbers preceded by a P. Let me know the numbers, and also tell me which engine (L) you have. There are likely to be fault codes stored in the engine controller memory even though the check engine light is not on. If nothing changes in the odometer window then go to an Autozone parts store or similar nationwide store where they may do a free readout using a plug-in code reader. An independent garage will do the readout for $40 or less.
Roland
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QUESTION: Thanks Roland,
Sorry for the delay in responding but I now have the car here in town for the weekend. Here's the info you requested:
No check engine light, Actron ODBII loaner from Advanced Auto says no fault codes, I/M monitors are all OK or N/A, no freeze frame data. (The on-off-on-off-on procedure didn't seem to work on this car, I'm familiar with it though, from our other '00 Mopar, a Voyager).
This morning, cold, had the symptoms not on initial startup and driving even on the slight upslope out of driveway onto street, but about 1/2 mile down the road when I braked to stop for test purposes after turning onto a quiet side street. This car has auto trans. Sensation was as if braking to stop in a manual trans car in a higher gear and not de-clutching. I shifted from D to 2 and it seemed to clear it up. After that it seemed fine.
I'll also mention potentially hearing in the fall, and now probably do hear some leaky/sticky lifter type noise when car first starts. At Adv. Auto I got some "Marvel Mystery Oil" and put 1/2 quart in. Also some Lucas "Upper Cylinder Lube and Injector Cleaner" and put almost all in.
Hope this gives you more to go on, Larry
ANSWER: Hi Larry,
The stalling out when you come to a stop as you described it sounds to me like the torque converter lock-up clutch is not disengaging as it should when you slow down and come to a stop. That will stall the engine for sure. There is an electrical plug on the side of the transmission facing the front of the vehicle that has 3 pins but only 2 actual wires that is what activates and should also deactivates the clutch first when you go over 40 mph and then deactiveates as you drop below that. You could remove the plug from the socket and see if that solves the problem by preventing the clutch from locking up in the first place. Other than waiting for warmer weather in the hopes that the clutch will disengage more positively you may just want to drive it without that lock up feature in use. There will be a slight decrease in mileage on the highway (over 40 mph) but it is probably worth it to solve the problem for now. Otherwise it means opening up the converter to service that clutch mechanism.
Roland
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QUESTION: Roland,
Funny you should mention the TCC. At the end of September I replaced the solenoid after code P0473 - Torque Converter Electrical came up. The solenoid coil measured open circuit so I replaced it. Code cleared after that and with slow acceleration in 40's mph range was able to feel it lock in about 43 mph so all seemed well. But that's about when this was first noticed. Though I will note the first time I felt it, while the A/C load was on, I shut it off and it seemed to go away - possibly coincidence, though at that time in the driveway, it hadn't had time to shift other than between reverse and first gear.
You have a great temporary (tempting permanent) solution idea to disconnect it and I can alternate between connect and disconnect to see if the problem comes and goes to confirm if this is the problem so I'll pursue that as the first step. As for permanent solution, I was concerned that maybe at highway speeds it would be harder (hotter) on the transmission to run with the slip for sustained periods, like this one gets with 80 mile trips on the expressway to come home, not to mention the hit to mpg, so went for the fix. Sounds like you think it will be OK with TCC disabled, i.e., will act just like older transmissions which I don't think had the lockup feature. If the mpg suffers a bit, beats working in the cold garage in winter. If I go permanent, I'll have to put a dummy load resistor in the connector to simulate the solenoid to keep the check engine lite off, esp. for inspection and not to hide other problems (which have been many).
For now, I'll alternate with and without TCC for troubleshooting and let you know the results.
Here is some additional history that may be pertinent as to why the lockup clutch is acting up, if it turns out that is the case: This spring the trans cooler leaked inside the radiator so coolant and trans fluid both got cross-contaminated. For the trans cleanup part, I completely flushed twice by tapping into the cooler lines and going from pepto bismol to pink the first time, then a full 13 qts flush the second time, and refilled including a can of Seafoam. Thought all was well. Could this have caused the lockup clutch damage - this happened on the expressway and was noticed by steam, etc. coming from the trans filler tube? Do you think a failure of the solenoid to lock up could be related to lockup clutch failure such that one causes the other? Also, I'll point out that when the valve body was out for TCC replacment, I saw a lot of 'rusty sediment' inside on the top dry areas of the trans around the shift lever hole. I wiped what I could out, but let it go since it doesn't seem to be showing up in the trans fluid (fluid and parts look clean and new with no dirt seen in any of the workings).
The TCC was my first venture into an auto trans further than changing filter. Once in there, I noticed how simple it really is, as long as you've got the special tools needed to get certain parts off and instructions on any tricky steps. I'm curious as to how far in the clutch mechanism is, and wouldn't mind the challenge if was the problem, weather is warmer, and have a reasonable chance of fixing it with jury-rigged substitutes for expensive special transmission tools ...
AnswerHi Dwayne,
You are ahead of me on the internal details of the 3-speed atx. I have that trans on my '89 LeBaron coupe but haven't had the need to get into yet. It seems to be a very good design. About all I can offer would be pages from the shop manual which I can either xerox and postal mail or if I find it still in use in '04 I should be able to get it off the '04 Neon repair manual I have on a CD and can email to you. Many automatics don't lock up, so I doubt there will be an issue with heat if you don't use the clutch on the highway. Please let me know if you find otherwise.
Roland
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