a straight ssssssss sound could be a vacuum leak
Are your Ltrims high, like in the 25 area when they used to be a lot lower? This happened to me when I installed the blower I knocked off a vacuum line to the blow off. The sssssss will get louder too as you rev as the engine is sucking in more air. Just a thought good luck

 

Glenn is allllll good. The sound he was hearing is the intake.....I think due to the heat, the truck is working a little harder and the intake is a little louder. We ran a scan on it and nothing showed up....

 

If your LTrims get that high you will throw an SES/MIL/CEL light. I know from experience.

When I installed my E-Fans, I forgot to tighten my hose clamps on my FIPK to TB and the intake tube fell off the TB! So when I ATAP'd it there were stuck at 25. I cleared the codes and it came back. I popped the hood and immediatly found my problem! Installed my hose clamps again, drove around some and the light was gone. Rechecked with ATAP and all was bueno.

 

yea I guess everythings cool. My ltrims dont average more than 6. I think I am just being paranoid and overly sensitive. Maybe the old cast iron maniolds were muffling up sounds I didnt hear before. Also maybe my truck is breathing better with the headers SO the intake noise is more pronounced. Either way no codes or signs of leakage.

Dr. blownchevy also checked my engine with is supercool scanner and stethoscope and it passed his professional diagnosis. Thanks DOC!

Hey what does everyone think is a good Ltrim average to have? Just curious since I am averaging 6.
Im sure HitmanX has some input on this.

 

You'll definately notice more noises after putting on headers. They're alot thinner than the cast manifolds and transmit more engine noise. I have a similiar noise that I started hearing after installing the FLP's but, it's not a leak. It doesn't even sound like a leak, it just sounds like the actual exhaust pulses whooshing down the pipes.

Check your Ltrims at WOT. If they're positive get them down to zero and retune for WOT. If they're not positive at WOT and are averaging +6 at part throttle then don't worry about them.

John

 

Mines about the same way. And when I go to WOT they freeze anywhere between +2 and +6. I was thinking about a maf translater to correct it but some people have said they are crap and don't work so I'm still looking into the issue before spending any money.

 

Hey marineblue glad you got it worked out. I was wondering about how the muffler shop welded the flanges to the cats. Did they do it from the outside or the inside? The guy that did mine did it from the inside and I think the welding stuff is restricting the exhaust flow. Just wondering if that is normal...

 

The welds on my trucks pipes were all from the outside. How could welds be done from the inside? Its late so maybe my tired brain cant comprehend what you are saying.

 

He welded the flange to the pipe from the inside and then grinded it smooth. He said the weld wouldn't stick to the outside for some reason. I think he was just dumb.