Rough Idle/Engine Dying After Stopping
Thread Starter
Pro
Joined: Mar 2008
Posts: 552
Likes: 2
From: Dubuque Iowa
Rough Idle/Engine Dying After Stopping
1987 Vette with a Manual Tranny
Engine always starts up quickly and idles well, however when taking it out of gear at a stop sign or a stop light my RPM's drop to 200-400 and sometimes it dies. If it doesn't die it will soon return to normal idle of 700-800 RPM. If it Dies it starts again easily.
Any Idea what the problem could be??
It accelerates extreamly well under partial or heavy throttle. Never misses.
Last night it was dying at stops more than usual.
Engine always starts up quickly and idles well, however when taking it out of gear at a stop sign or a stop light my RPM's drop to 200-400 and sometimes it dies. If it doesn't die it will soon return to normal idle of 700-800 RPM. If it Dies it starts again easily.
Any Idea what the problem could be??
It accelerates extreamly well under partial or heavy throttle. Never misses.
Last night it was dying at stops more than usual.
Heel & Toe
Joined: Sep 2009
Posts: 16
Likes: 0
Rough Idle/Engine Dying After Stopping
I had the same problem. Ran perfect under acceleration. Coming to a stop, coasting would stall or almost. Always started right back up. Turned out to be the alternator. Had it rebuilt and hasn't happened since.
Hope that helps!
Hope that helps!
Thread Starter
Pro
Joined: Mar 2008
Posts: 552
Likes: 2
From: Dubuque Iowa
Really?? Well will have to watch my volts then!
Heel & Toe
Joined: Sep 2009
Posts: 16
Likes: 0
No Codes!
Mine was throwing no codes either!
Now I'm having a random no start, no power, nothing. Well, it only happened once. Holding my breath every time I start her. I'm thinking bad ground, maybe? Still no codes.
Now I'm having a random no start, no power, nothing. Well, it only happened once. Holding my breath every time I start her. I'm thinking bad ground, maybe? Still no codes.
Thread Starter
Pro
Joined: Mar 2008
Posts: 552
Likes: 2
From: Dubuque Iowa
yeah probably a loose wire somewhere. I won't be able to check my volts till this weekend cuz I'm workin on the road.
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Pro
Joined: Mar 1999
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From: Oslo, Norway
Hi I have an 85 manual 4+3.
I have modified the engine with a larger cam and ported plenumm and intake and large tube runners. Had idle problems which showed to be vacuum leak and EGR valve. Then it stalle as you describe. Everything were alright all sensors looked ok with scanning tool. BLMs and INT looked alright. I adjusted the min idle air and set ita little higher than the book said. It became a little better. Then I discovered that the courtesey light flickered we idling. and the voltage were withinin reason and it charged alright.
It was the voltage regulator which oscillated. I changed the alternator as it had 70000 milies. The flickering dissapeared and the stalling also dissapeared now I am happy especially as I changed the injectors to the gen III Bosch from FIC. It starts very fast when warm also and repond very well .
I think for me it was the alternator that gave wrong voltage to the computer and injectorors when on idle and therefore disturbed the dutycycle on the injectors and maybe the signal from maf. Anyhow the stalling is fine now and I am very satisfied with it
I have modified the engine with a larger cam and ported plenumm and intake and large tube runners. Had idle problems which showed to be vacuum leak and EGR valve. Then it stalle as you describe. Everything were alright all sensors looked ok with scanning tool. BLMs and INT looked alright. I adjusted the min idle air and set ita little higher than the book said. It became a little better. Then I discovered that the courtesey light flickered we idling. and the voltage were withinin reason and it charged alright.
It was the voltage regulator which oscillated. I changed the alternator as it had 70000 milies. The flickering dissapeared and the stalling also dissapeared now I am happy especially as I changed the injectors to the gen III Bosch from FIC. It starts very fast when warm also and repond very well .
I think for me it was the alternator that gave wrong voltage to the computer and injectorors when on idle and therefore disturbed the dutycycle on the injectors and maybe the signal from maf. Anyhow the stalling is fine now and I am very satisfied with it
Thread Starter
Pro
Joined: Mar 2008
Posts: 552
Likes: 2
From: Dubuque Iowa
Hi I have an 85 manual 4+3.
I have modified the engine with a larger cam and ported plenumm and intake and large tube runners. Had idle problems which showed to be vacuum leak and EGR valve. Then it stalle as you describe. Everything were alright all sensors looked ok with scanning tool. BLMs and INT looked alright. I adjusted the min idle air and set ita little higher than the book said. It became a little better. Then I discovered that the courtesey light flickered we idling. and the voltage were withinin reason and it charged alright.
It was the voltage regulator which oscillated. I changed the alternator as it had 70000 milies. The flickering dissapeared and the stalling also dissapeared now I am happy especially as I changed the injectors to the gen III Bosch from FIC. It starts very fast when warm also and repond very well .
I think for me it was the alternator that gave wrong voltage to the computer and injectorors when on idle and therefore disturbed the dutycycle on the injectors and maybe the signal from maf. Anyhow the stalling is fine now and I am very satisfied with it
I have modified the engine with a larger cam and ported plenumm and intake and large tube runners. Had idle problems which showed to be vacuum leak and EGR valve. Then it stalle as you describe. Everything were alright all sensors looked ok with scanning tool. BLMs and INT looked alright. I adjusted the min idle air and set ita little higher than the book said. It became a little better. Then I discovered that the courtesey light flickered we idling. and the voltage were withinin reason and it charged alright.
It was the voltage regulator which oscillated. I changed the alternator as it had 70000 milies. The flickering dissapeared and the stalling also dissapeared now I am happy especially as I changed the injectors to the gen III Bosch from FIC. It starts very fast when warm also and repond very well .
I think for me it was the alternator that gave wrong voltage to the computer and injectorors when on idle and therefore disturbed the dutycycle on the injectors and maybe the signal from maf. Anyhow the stalling is fine now and I am very satisfied with it
So I took it for a drive last night and saw that my voltage is between 13.7-14.1 while it is running good. When the idle drops the voltage is around 12.1-12.3 or so... I bet the alternator is the problem!
I have replaced the EGR last fall, and also put a full melrose exhaust system with headers on the car. New O2 sensor, new temp guage, new knock sensor, new plugs 'AC/Delco Rapidfires...
Heel & Toe
Joined: Sep 2009
Posts: 16
Likes: 0
Rough Idle/Engine Dying After Stopping
So I took it for a drive last night and saw that my voltage is between 13.7-14.1 while it is running good. When the idle drops the voltage is around 12.1-12.3 or so... I bet the alternator is the problem!
I have replaced the EGR last fall, and also put a full melrose exhaust system with headers on the car. New O2 sensor, new temp guage, new knock sensor, new plugs 'AC/Delco Rapidfires...
I have replaced the EGR last fall, and also put a full melrose exhaust system with headers on the car. New O2 sensor, new temp guage, new knock sensor, new plugs 'AC/Delco Rapidfires...
Heel & Toe
Joined: Sep 2009
Posts: 16
Likes: 0
Rough Idle/Engine Dying After Stopping
Well, I finally got to the bottom of my no crank, no power, no anything! It turned out to be the simplest damn thing. Previous owner installed a quick disconnect on neg. battery terminal. First thing I checked, was tight, I thought. I was looking for loose connections in the dark last night. Wiggled neg. battery terminal, interior lights flickered. I took the quick connect off. So far so good.
