Normal Idle??
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Joined: Mar 2003
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From: Woolwich Me
Normal Idle??
Since I bought my 90 ZR1 I have had a consistent high idle that hangs for about 2-3 seconds and then drops down to around 800
It will hang @ 1200-1500 then drop
Could it be the vaccuum hoses under the plenum (Hope not) or is this typical of the LT5
It is very consistent
Any thoughts?
1990 Blk Blk #1138 :confused:
It will hang @ 1200-1500 then drop
Could it be the vaccuum hoses under the plenum (Hope not) or is this typical of the LT5
It is very consistent
Any thoughts?
1990 Blk Blk #1138 :confused:
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St. Jude Donor '03, '17
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Re: Normal Idle?? (jhoward)
I think it is normal for the 90-91 to do that when you stop at a traffic light eg...mine does it at times and I think it can be fixed by getting a new computer PROM from GM
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Re: Normal Idle?? (jhoward)
Mine stays about 1100 or 1200 until I come to a stop than it drops to around 750
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Thread Starter
Intermediate
Joined: Mar 2003
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From: Woolwich Me
Re: Normal Idle?? (LowFlight)
I did get the PROM update done but this did not change the idle
sounds like it a feature not a problem for the majority of the respondents
Thanks to all :seeya
sounds like it a feature not a problem for the majority of the respondents
Thanks to all :seeya
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Joined: Apr 2002
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From: Richardson TX
Re: Normal Idle?? (jhoward)
Try this :
At idle, with the car in neutral and on level ground - pump the brake pedal repeatedly. Watch the tach and notice that your idle will rise and fall just a tad.
I believe that when you're coming to a stop and you brake, the brake system is using vaccum and the idle will fluctuate a touch. It's normal - it is more pronounced in my ZR1 than other cars though.
[Modified by LM, 6:05 AM 5/12/2003]
At idle, with the car in neutral and on level ground - pump the brake pedal repeatedly. Watch the tach and notice that your idle will rise and fall just a tad.
I believe that when you're coming to a stop and you brake, the brake system is using vaccum and the idle will fluctuate a touch. It's normal - it is more pronounced in my ZR1 than other cars though.
[Modified by LM, 6:05 AM 5/12/2003]
