Topic: Chugga Chugga
in Forum: C3 Engines
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I've got a question about what a normal 82 engine should sound like at a cold start. We have zero experience with vettes of any year so don't know if the chugga chugga sound ours makes when first started is normal.
Basically it sounds like a steam train when first started up. Not a skipping kind of thing but a "chuggy" idle.
It smooths out and sounds fine after a couple of minutes so maybe this is normal for the crossfire 350? It seems to idle a little high once it smooths out but then again we're used to early sixties big Chevy sounds. The car has only 43000 original miles. On the road it runs great. Is the chugging thing at startup normal?
Any advice will be appreciated. Thanks!
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Duncanville, TX - USA
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Is it blowing any black soot from the tailpipes when it starts, and "chugs"? If so, you may have an injector that is leaking on one of the throttle bodies.
You may also have an issue with the coolant temp sending unit tricking the EMC into thinking it is way colder than it really is. This would cause the ECM to request more fuel for the cold start-up that the engine may not need.
The high idle may indicate the throttle bodies just need a cleaning, or there may be a small vacuum leak somewhere.
See if you can find someone to do a "scan" on it, and see if there are any codes set in the ECM. That would give you an idea of where to start in the diagnosis.
You may also have an issue with the coolant temp sending unit tricking the EMC into thinking it is way colder than it really is. This would cause the ECM to request more fuel for the cold start-up that the engine may not need.
The high idle may indicate the throttle bodies just need a cleaning, or there may be a small vacuum leak somewhere.
See if you can find someone to do a "scan" on it, and see if there are any codes set in the ECM. That would give you an idea of where to start in the diagnosis.
Joel Adams
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Cramerton, NC - USA
Joined: 8/22/2006
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Vette(s): black 1982 coupe slate gray interior, 350 crossfire, 1985 fuel pump, Steeroids R&P conversion
Janice, idle problems with crossfires is a common thing. If the chugga chugga sound you refer to is just a rough idle mine does it too on cold startup for about a minute. Mine starts and idles high for a minute or so then settles down to a normal idle of about 650 rpms I think the high idle on start up is pretty well common on crossfires. Joels suggestions may explain part of the sounds you are hearing and I would definately check the coolant temp sensor, I have replaced all of my sensors and it helped some with the problem. Crossfires have their quirks but in general they are reliable and run well. Ive had little problems with mine. Im sure other 82 owners will chime in here with whether or not theirs idles rough at cold startup.
On a cold start mine will ossilate on the idle between 1000 and 700 for about 30 seconds. Then you hear a click and the idle is steady at 850.
Someone told me the intake manifold might have a leak, but it runs fine,
If you can find someone in your area that knows Crossfires, see what they think.
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