The lo3 has been acting weird as of late.The tach has been bouncing,sometimes the engine surges a little....I finally decided on the EGR,but its hard to find free time to work on the camaro when I work 60 hours a week.Anyway,today I'm coming home and suddenly PFFFFFT! theres a sound like a release of air from under the hood.It was a sudden,short,loud PFFFT!(I cant think of how else to descibe it).When it happened,the car jerked like for a second it wanted to die.All this is while driving.Does this sound EGR related too?

 

it really doesn;t sound like the EGR to me...sounds vaccuum related simply due to the air noise you heard.

 

Make sure none of the plug wires came loose from their spark plugs.

 

The EGR systems on most of our cars are very tempramental. If there was even the slightest problem, you'd probably be getting a code for the EGR. How are all your TB seals?

 

Here's a thought...I had the SAME thing on my L03 in my Caprice...clogged cat...it acts like a bad EGR, and then actually blows a hole in the air line coming from the pump...get under it and see if you can hear where the noise is coming from...

Just my $.02...

Jim

 

Hmm, yeah, good idea. I just took the 190K mile cat off my truck for that reason.

 

Thanks guys.
Quick follow-up...
I popped the hood for a look after it all cooled off and found that the vacuum cap from the hose under the throttle body,which I capped off after installing a open element, had come off and was lying on the intake manifold.I assume that was the "bb gun" noise I heard.Why would it shoot off?I put it back on (after dabbing on some gasket seal...heh heh heh come off now...) but the tach still bounces and the cars still sluggish and sputters. I know I have a exhaust leak in the exhaust manifolds, can that do it?

Btw...I've already done a tune-up(plugs,distibutor cap,rotor and fuel filter).It helped but it started acting up again a few days later.

 

I saw a very similar thing at work with a tbi camaro and the guy had no cat and no muffler well long story short the egr valve was opening up and causing it to run like yours but, he had a egr code though