Running really rich after some engine work
Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 7,890
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From: FL
Running really rich after some engine work
I posted this in the general C5 section and didn't get any immediate replies. Hopefully this is the more appropriate place and I can get some help.
http://forums.corvetteforum.com/show...3&forum_id=103
http://forums.corvetteforum.com/show...3&forum_id=103
Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 7,890
Likes: 0
From: FL
Would a vacuum leak really do that?
It's misfiring horribly at low rpms and the idle is slightly lower.
When you get over 2000rpms you can only feel it sometimes if you push the gas very very slowly. At Wide open throttle you can't tell.
It's misfiring horribly at low rpms and the idle is slightly lower.
When you get over 2000rpms you can only feel it sometimes if you push the gas very very slowly. At Wide open throttle you can't tell.
Pro
Joined: Aug 2004
Posts: 575
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From: Richmond Hill Ontario
Since the trouble started after you removed the intake manifold it's logical to assume that either the intake a vacuum hose is the problem. You really need to recheck all your connections, especially at the rear of the intake. Take a spray like WD40 but something that's not flammable (liquid wrench) and spray it around the intake where it seals to the head. If you've got a leak you'll hear the motor smooth out.
Drifting
Joined: Oct 2003
Posts: 1,540
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From: bloomfield nj
sounds like a air or vacuum leak.check and see what faults you have,if any.if the problem happened after taking of the intake,i would think either a pinched broken vacuum line or you had a intake gasket move.if you were actually running rich[02 voltages high],your long term fuel trims should be in the minus[pcm pulling fuel out].if you have a air/vacuum leak[o2 voltages low],your long term fuel trims will be in the plus[pcm fattening up the fuel].without a scanner you can't look at the voltages or the trims,but check your faults,with the cats out,you should have cat faults,no fuel/mixture faults.if you pinched a intake gasket or cracked a vacuum line,spray some carb cleaner around the intake with the car running,if the rpm's raise you found your leak.also listen for a hissing noise,if you hear one,you have a vacuum leak.
Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 7,890
Likes: 0
From: FL
P0420 TWC System Low Efficiency Bank 1
P0430 TWC System Low Efficiency Bank 2
These are the 2 codes that I pulled. The others I have all have to do with the A/C. Do these have to do with removing the cats?
So the vacuum leak would cause the car to run lean right?
I will recheck everything again but I don't really know what I'm looking for since my friend did most of the work. I put some simple things back at the very end.
P0430 TWC System Low Efficiency Bank 2
These are the 2 codes that I pulled. The others I have all have to do with the A/C. Do these have to do with removing the cats?
So the vacuum leak would cause the car to run lean right?
I will recheck everything again but I don't really know what I'm looking for since my friend did most of the work. I put some simple things back at the very end.
