no start after rough idle question
Thread Starter
Burning Brakes
Joined: Jul 2003
Posts: 888
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From: Angola IN
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no start after rough idle question
Hey guys maybe you can help. Took my 89 out today for the first time today. Ran about 50 miles without an issue. Got to my turn around point and it started idling rough, and was down on power, made it back home after a trip with poor power pulled into the garage with a rough idle still there about 5-600 rpm idle surging, then it died, wouldn't restart. Have it on the charger now.
I thought it was just poor gas from its winter sleep, until I started to not be able to pull hills, lousy throttle response, and no kick down (auto tranny).
Any ideas on a start point? The no start has me concerned. I know it could be a number of things, but going from running fine, to rough idle and now a no start.
BTW its a 1989 with auto tranny and 27K miles.
BTW I have a manual from the 86 I used to own, are the check procedures and methods the same for the 89? Check voltages, fuel pressures the same? Just wondering if the no start flow chart in the manual is the same.
Thanks guys.
I thought it was just poor gas from its winter sleep, until I started to not be able to pull hills, lousy throttle response, and no kick down (auto tranny).
Any ideas on a start point? The no start has me concerned. I know it could be a number of things, but going from running fine, to rough idle and now a no start.
BTW its a 1989 with auto tranny and 27K miles.
BTW I have a manual from the 86 I used to own, are the check procedures and methods the same for the 89? Check voltages, fuel pressures the same? Just wondering if the no start flow chart in the manual is the same.
Thanks guys.
Last edited by garandfan; Apr 1, 2009 at 02:51 PM.
Melting Slicks
Joined: Jan 2001
Posts: 2,940
Likes: 5
From: Chesapeake VA
Could be a sensor that gets wierd when it heats up.
If it prevents the car from starting, then that should limit the number of potential sensors to look at.
When it fails to start, does it spin normally? Does it try to fire?
If it prevents the car from starting, then that should limit the number of potential sensors to look at.
When it fails to start, does it spin normally? Does it try to fire?
Thread Starter
Burning Brakes
Joined: Jul 2003
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From: Angola IN
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OK I let it do a complete cool down, went out for a drive, when cold it runs smooth, and shifts properly, when it gets warm, the rough operation starts, and will not shift properly. Here is what it does, at full temp when you kick it down, it will down shift, but feels like it is slipping, also the rpms, are severly limited, like 3-4,000 rpm, from a 1,400 or so run in OD.
Now I am puzzled, do I have one issue with lack of throttle response? or is two issues with throttle, and tranny??
BTW no codes are present, and cold starts are smooth, Runs the same with TPS disconnected, and in both open and closed loop (with A & B jumped during run condition).
Now I am puzzled, do I have one issue with lack of throttle response? or is two issues with throttle, and tranny??
BTW no codes are present, and cold starts are smooth, Runs the same with TPS disconnected, and in both open and closed loop (with A & B jumped during run condition).
Corvette Enthusiast
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Good luck on this! I would maybe un plug MAF and see how it runs. I have had MAF issues without a code before.
Heel & Toe
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From: Deerfield New York
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Thread Starter
Burning Brakes
Joined: Jul 2003
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From: Angola IN
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So after a day of working with this issue, I have two distinct issues. The tranny will require a visit to the tranny shop for a valve body tear down, and de-gum it. Valves are sticking.
The idle issue still has me perplexed, Runs fine in open loop with out peter commands, once it is warmed up and enters clossed loop is were the rough idle begins.
I'll do some more research, and open to any ideas. BTW the TPS voltage readings are normal.
I guess this is payback for a long time in storage!!
The idle issue still has me perplexed, Runs fine in open loop with out peter commands, once it is warmed up and enters clossed loop is were the rough idle begins.
I'll do some more research, and open to any ideas. BTW the TPS voltage readings are normal.
I guess this is payback for a long time in storage!!
