rough starting engine 92 c/k
bskit88
02-23-2006, 05:38 PM
5.7L v8 with 50K miles (automatic tranny). Had a tuneup 2 months ago and replaced fuel pump and filter 2 weeks ago.
Upon initial startup each day engine sputters with slight misfires (or backfires?) it comes close to stalling. After 30 seconds or so, engine sounds and runs great. Idle seems to be a little low at stop lights with my foot on the brake but doesn't stall.
I'm in Southern California, so it is not really cold. It's been 75 degrees outside when starting engine.
If I do nothing, will this get worse or harm anything else down the road?
Or should I try and fix it?
Thank you
Upon initial startup each day engine sputters with slight misfires (or backfires?) it comes close to stalling. After 30 seconds or so, engine sounds and runs great. Idle seems to be a little low at stop lights with my foot on the brake but doesn't stall.
I'm in Southern California, so it is not really cold. It's been 75 degrees outside when starting engine.
If I do nothing, will this get worse or harm anything else down the road?
Or should I try and fix it?
Thank you
Bob B
02-24-2006, 10:28 AM
Ok First, is this a carburator engine?
If so it sounds like the choke isn't closing.
When it is cold, take the air filter off and look down the carb. The butterfly is probably open from th last run.
Use the linkage or press the gas pedal one time to the floor. This should allow the choke to pop shut. If it doesn't you found the problem.
Holding the carb linkage open, the choke should be trying to move and might need a bit of help. If so it needs to be cleaned and lubed.
If it doesn't even try to close, it may have been adjusted wrong by a previous owner. Usually it's not too hard to adjust.
If your truck is FI, then never mind!
Bob B
If so it sounds like the choke isn't closing.
When it is cold, take the air filter off and look down the carb. The butterfly is probably open from th last run.
Use the linkage or press the gas pedal one time to the floor. This should allow the choke to pop shut. If it doesn't you found the problem.
Holding the carb linkage open, the choke should be trying to move and might need a bit of help. If so it needs to be cleaned and lubed.
If it doesn't even try to close, it may have been adjusted wrong by a previous owner. Usually it's not too hard to adjust.
If your truck is FI, then never mind!
Bob B
2000CAYukon
02-24-2006, 11:51 AM
92 is TBI. You could have a bad fuel pressure regulator that leaks gas into the intake over night. Take the air cleaner off and see if you smell gas in the morning. You could also plug the vacuum hose to the EGR to make sure that it is not causing your problem.
Other possiblities could be IAC, MAP, pickup coil, coil.
A scan tool hooked up when the problem occurs could also help trouble shoot the problem. Any codes stored?
//2000CAYukon
Other possiblities could be IAC, MAP, pickup coil, coil.
A scan tool hooked up when the problem occurs could also help trouble shoot the problem. Any codes stored?
//2000CAYukon
bskit88
02-24-2006, 02:25 PM
Thank you,
Yes it is FI.
I will check out these suggestions. I will do a search and find out about "any codes stored" as I do not know what this means.
If I do nothing am I putting myself at risk of being stranded on the road or causing any major problems?
Yes it is FI.
I will check out these suggestions. I will do a search and find out about "any codes stored" as I do not know what this means.
If I do nothing am I putting myself at risk of being stranded on the road or causing any major problems?
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