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Am I looking at ECU related issue, fluke, or something else?

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Old 01-02-14, 11:13 AM   #1
tjschraf
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Default Am I looking at ECU related issue, fluke, or something else?

I have searched quite a bit and read quite a bit and for the issues I am experiencing- I see a couple things that can be the culprit. Seeing as I have a 1995- I am suspecting that the ECU capacitors would fix the problem. However, I plan to sell this car in 3 months and do not really want to deal with any work at the moment.

I drove about 70 miles yesterday and parked my LS for the day in cold Ann Arbor, Michigan for the winter classic. I came out and when the car started it died immediately and an engine light flashed. I tried again same thing. After that, I just kept revving the engine, I revved it the entire time sitting in trafffic. Once it warmed up it seemed to steady out and begin to idle properly. It did however shut off a few times. And after parking for 2 hours more it did it again.

This morning it worked just fine after being in a warm(er) garage for the night.

Is it possibly the fact that It was very cold and it was a fluke, that I was low on gas (1/8 and after fuel up it did not do it again), that I need to look at my TPS or Idler control, or just general tune up things like spark plugs?


I am believing it to be ecu related since I do have a few of the issues:
1. The idle was extremely low and does sometimes surge
2. The radio light is out (not sure if it is ECU related)
3. The trasnmission has a jerk when you let up on the gas when on highway
4. Original ecu (almost 20 years old)
5. The car never really revs higher than 3k rpm with my foot mashed down unless power button is on
6. It seems to hesitate to start a bit and it is not battery related.


I have 141k miles on it and it is an otherwise really nice car.
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Old 01-02-14, 11:20 AM   #2
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My suggestions:
- change ECU caps, because its cheap and easy!
- clean your throttle body
- check the transmission mount and if needed - replace
- check transmission oil and if needed - replace
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Old 01-02-14, 11:33 AM   #3
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Any codes?
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Old 01-02-14, 12:13 PM   #4
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Symptoms seem to chime with the ECU but you'll have to check other areas as well. Vacuum lines, kinked or frayed insulators on key parts of the wiring harness...etc. If this is an ECU issue, fixing it isn't big $ and the car will retain a better sale value when running properly.
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Old 01-02-14, 04:03 PM   #5
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The jerking problem when letting off the gas is an ECU defect that affects ALL the early 95 models which didn't show up until about 5 or 6 years later. Its remedied by getting a specific ECU and cruise control computer with part-numbers made later in the year. I've read they have low idle issues and stalling problems with the same ECU being the blame, but I never experienced that particular problem in mine before swapped them out.

The radio being unlit is simply burned out bulbs.
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Old 01-02-14, 04:33 PM   #6
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Hi, YoshiMan.
If you are referring to TC006-04, it was applicable to all 2004 LS430s, and 2005 cars before serial 005700 .
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Old 01-03-14, 05:35 AM   #7
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Thank you all. It has not happened again. It seems weird that after fueling up I have not experienced it. But I am still not sure. And obviously, I will need to take care of my ECU regardless. I appreciate the help of the forum.

Also, no engine lights on. The engine light came on for a second as the car shut off each time but when it fired back up it was off.
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Old 01-10-14, 05:53 AM   #8
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Update after a week and a half and ~600 miles. It has not happened again. I believe it was due to being so low on fuel. I have no doubts though when time frees up that I need to do the ECU
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