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1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

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Old 02-29-2008, 05:31 PM   #1
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I installed my new PEMs today, that was quite a battle. The problem is now I have a bit of a rough idle. Engine runs fine when driving, no misses, stutters, nothing. But when I just idle, it'* rough. Any clues on what this might be? Where to look? Etc. Was thinking O2 sensor, I checked vac. lines and they all look good. I don't see anything out of place. Any thoughts will be helpfull.
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Old 02-29-2008, 06:00 PM   #2
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Just got a engine light, the error is
P0171
Powertrain: Fuel trim system lean bank 1



I'm thinking it may be my trim table. I disconnected the batery for 5 or 10 mins. Still rough but it will take a few starts and some driving to reset them. Any other ideas?

After disconnecting the battery I got a second SES light

P0300
Engine misfire detected

Seems like it runs good, then rough, then good again. When first started, smooth idle. Then gets rough after a short time. Smooths out for a bit, the rough again.
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Old 02-29-2008, 11:07 PM   #3
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How long would you recomend disconnecting the battery to reset the trim tables? How long will the relearn take, number of starts, time running, etc.
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Old 03-01-2008, 12:29 PM   #4
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Up date here. Now I got a code P0172 which is bank 1 rich, which seem sto be a condridiction of the P0171 code. The only thing I can think of is I had picked up the O2 sensor with my dirty gloves and wasn't thinking and picked it up by the probe side. Is it possible I messed up the sensor? I'm planning to order a new one anyways.

I have ruled up a spark plug wire close to the O2 wire, and have cleaned my battery wires. The O2 sensor is the only thing I touched.
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Old 03-01-2008, 01:21 PM   #5
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What brand O2?

Have you checked your coils?
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Old 03-01-2008, 01:48 PM   #6
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Quote:
Originally Posted by azu
What brand O2?

Have you checked your coils?
The O2 is what ever came with the car. I suspect it'* going because my MPG is down, I only average about 18MPG, last year I was getting about 28 hwy and average 23. I'm only getting about 22 hwy now. I'm planning to order a Desco some time this weekend.

The coils look good but I will give them a real close look.

I also checked for Vac leaks, found nothing.

I'm also getting a P0748 code, Pressure control solenoid. I checked my trans fluid and it was low, so I topped it off.
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Old 03-02-2008, 10:50 AM   #7
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Looks like I found the problem, just need to get it fixed.



Looks like it got twisted when I was working on the exhaust manifolds.



A bit of a vac leak. Never checked down in that area. This is from the EGR valve to the intake manifold. Going to solder it if possible for a temp fix until I can get a replacement. Any ideas who may have this? Or if anyone has one laying around, I'll take it.
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Old 03-02-2008, 12:01 PM   #8
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Solder will melt. It needs to be brazed at the bare minimum.

Coils will have no effect on fuel trims. Ignore them if you didn't have a problem before. Your misfire is due to crappy AFR'*.

I suggest a wrecker for a replacement.
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Old 03-02-2008, 12:20 PM   #9
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I used some JB weld to fix it for now. Not a perminant fix by any means. But hopefully it will hold good enough till I get a replacment. It cant be any worse then it was.
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Old 03-02-2008, 12:25 PM   #10
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Until you suck in a broken piece of JB Weld and it wipes out your rotors.

I suggest undoing that one and using the highest temp-rated RTV you can find instead.
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