Warm start problem
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Burning Brakes
Joined: Sep 2003
Posts: 1,197
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From: Wine Country, CA
Warm start problem
Recently I been experiencing an occassional warm start problem. Normally my '82 fires right up and settles into a nice smooth idle.
However, every once and a while, after it has been driven a while and shut off, when I try to start it again, it fires and just kind of goes BLAAaaa, won't idle or rev and dies. Kind of feels like it's missing or not running on all 8 cylinders.
If I fire it up again and play with the throttle I can keep it from dying and within a minute or so it smooths out and idles OK.
Anyone had the same problem or have any thoughts on what the problem might be? Thanks.
James
However, every once and a while, after it has been driven a while and shut off, when I try to start it again, it fires and just kind of goes BLAAaaa, won't idle or rev and dies. Kind of feels like it's missing or not running on all 8 cylinders.
If I fire it up again and play with the throttle I can keep it from dying and within a minute or so it smooths out and idles OK.
Anyone had the same problem or have any thoughts on what the problem might be? Thanks.
James
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From: Australia
If CIS, check some recent posts on hot start solenoid problems, or leakage from same....mine takes a bit of cranking when half hot to fire. Shut down only minutes is fine, but 1 hour, more cranking.
jp 83 Euro S AT49k
jp 83 Euro S AT49k
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I have this same problem with my '93. Starts great first thing in the morning - no messing with the gas pedal at all. But after driving it a bit, any re-start requires almost holding the gas pedal to the floor.
Drove the car up to SLC today and talked to Dave Lomas about it. One possibility he raised is that of a "leaky" injector(s). This would possibly allow an extra rich fuel mixture and result basically in flooding the engine. When you let the car sit overnight, the flooding would resolve - so then it starts fine.
And, if you floor the accelerator pedal and hold it down - which actually increases the amount of air, not fuel - it hot-starts better. (This is what you do to start a flooded car.)
He watched as I started my car, and indeed the tailpipe exhaust was quite dark - too rich. You might have someone check the appearance of the exhaust as you hot-start the car.
Just a thought.
Drove the car up to SLC today and talked to Dave Lomas about it. One possibility he raised is that of a "leaky" injector(s). This would possibly allow an extra rich fuel mixture and result basically in flooding the engine. When you let the car sit overnight, the flooding would resolve - so then it starts fine.
And, if you floor the accelerator pedal and hold it down - which actually increases the amount of air, not fuel - it hot-starts better. (This is what you do to start a flooded car.)
He watched as I started my car, and indeed the tailpipe exhaust was quite dark - too rich. You might have someone check the appearance of the exhaust as you hot-start the car.
Just a thought.
Under the Lift
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Flooding from leaky injectors is a good guess. Cold starts are not affected as the gas evaporates by then. Classic is if you run the car, shut it off when warm, it will restart if you try immediately (not yet flooded), but if you let it sit 10 minutes to an hour ( time enough to flood but not evaporate), it will have great difficulty restarting. Let it sit 8-12 hours, it is fine again.
Under the Lift
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bigs: Get them cleaned. The services, like Marren or Cruzin
http://www.injector.com/injectorservice.php
http://www.cruzinperformance.com/fuelinj.html
will clean and flow match the injectors for a very resonable fee.
http://www.injector.com/injectorservice.php
http://www.cruzinperformance.com/fuelinj.html
will clean and flow match the injectors for a very resonable fee.
Inventor
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Could be the cold start thermo-time switch.
When the car is warm and off, unplug the cold start thermo-switch (faces forward on the coolant bridge), then start the car and see if the problem persists.
When the car is warm and off, unplug the cold start thermo-switch (faces forward on the coolant bridge), then start the car and see if the problem persists.
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Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 1,197
Likes: 29
From: Wine Country, CA
Thanks guys:
Gives me a few things to check. It doesn't happen very often, but often enough that I was starting to get a little concerned.
It happened yesterday at our 1st autocross of the season. Did my runs then did a work session. When it was time for my second set of runs it did the BLAAaaa, phft, phft, phft, die, thing when I tried to fire it up.
By the way, I had the 928 ttd (there were three of us) until the very last run of the day when Greg in an "85 pipped me by 2 tenths of a second. Must have been that extra 68 hp
James
Gives me a few things to check. It doesn't happen very often, but often enough that I was starting to get a little concerned.
It happened yesterday at our 1st autocross of the season. Did my runs then did a work session. When it was time for my second set of runs it did the BLAAaaa, phft, phft, phft, die, thing when I tried to fire it up.
By the way, I had the 928 ttd (there were three of us) until the very last run of the day when Greg in an "85 pipped me by 2 tenths of a second. Must have been that extra 68 hp
James
