I recently took of S/C to paint and just put it back on and was making sure everything was alright. Well, seems everything is pretty good, except for idle.

It kinda likes to idle around 1000 where it use to be around 800. And it kinda makes a pssh sound erradically. Like it would sound normal and a pssh pssh (kinda like air and you can feel a small burst come out thats different then the rest). It will do it 1-2 times, stop for a sec and do it again.

I test drove it and I still hit about 16 psi in boost and WOT sounds normal. Is this a normal sound, because maybe I just overlooked it and now pay more attention making sure everything is working normally.

MODS:
OTTP stage 1 with 2.85 pulley
OTTP H/E
GMPP cat back.
Injen Intake

 

the psshh sounds u are talking about, comes from the exhaust?

 

yeah. I tried cleaning the TB, but still kinda happens. Maybe I didn't clean it well enough? Now when I rev it, it will float. Like Ill rev to 4k, then it will drop to about 1k, jump to 2k, then slow float back to around 800-1k

 

maybe it's from ur sc gasket...could be leaking...
hence vac leak which could cause poor idle, and more then likely the exhaust notes doing that.
just my 2 cents I have a a problem like that..happened after I pulled my sc to replace my alternator...haven't put a new gasket in yet, but it's going to the dealer in a couple of days for a comp diag. to check to see whats up.

 

are you running ottp stage1 kit with ottp tune?NO!! YOU FAILsend the tune file to OTTP GUYS,they know how tunes and stop getting bbq tunes from terry...

 

did u clean ur TB when u took of ur sc??? if u clean off ur tb this seems to happen to everyone elce... when u clean it its used to having carbon build up in the spaces u can see through ur TB never closes and its hard to get a steady idle when its ... built in a way to have carbon build up on it for it to work at 100% function.... u pritty much took the gasket off of the TB by cleaning it but drive it around and it will be back to normal in no time.(once carbon builds back up... which i know sounds bad but its the truth)

 

its actually a modified OTTP tune, I run the same tune as brandon

You mean the orange piece between the TB and S/C?

where is the s/c gasket?

 

no i mean the throttle body>?? the whole thing... the plate that opens up alowing air to flow into the motor did u happen to use throttle body cleaner on it or carb cleaner? SC gasket is located between supercharger and manifold.

 

hmm? When I took it off there was no such gasket there? It just fit right over the holes...

I used brake cleaner

 

I used brake cleaner on some plastic parts a few years ago, and they just fell (crumbled) apart.
Hope you don't have the same problem.

 

TB isn't plastic lol.

 

I would remove the s/c again an check for proper placement on the gasket, could be a vacuum leak.

 

What gasket? There was no gasket when I took it off that I know of. It was bare metal on the S/C and the manifold. It just sat over the screw holes...

Edit: I also checked your site LSJwannabe and couldn't find a gasket for the S/C either...

Also, how bad is it to drive with a vaccum leak (if thats what it is and i need a new gasket). I mean, WOT seems fine, standard driving seems fine and I still hit full boost. Its just idle that seems funny.

 

The gaskert for the sc is a big metal on you probably missed it when you took it off it may have stayed on the manifold but there is one there

 

I'm assuming you have a boost guage.

What is your vacuum reading at idle and do you get full boost at WOT

 

Yeah, I have a boost gauge, but not sure how I would read vacuum. i do get full boot (or close to it, I get around 15-16 PSI with the 2.85.)

hmm, happen to know of any pics of it so I am sure I know what im looking for. If it did stay on the manifold the towels I used to cover it might of moved it?

 

vacuum is the opposite side of the boost gauge...

 

The boost gauge should be reading about 20 in mercury at idle.

Look at the gauge closely when the car is idling

 

Couple causes: bad s/c gasket, loose bolt, rotted vac hoses. Check all those, and not just visually. Pull the line, put back on, repeat for other connection points

 

Well, vacuum idles around 17.5-18.5. I revved it a bit to about 3k a couple times and it dropped to about 22-23 then went back to idle at around 17.5-18.5

So it seems to me its mostly probably the S/C gasket so I guess that will be the first thing ill check. Is it pretty safe to drive till I can get time to check it?

Also, I did a search again and seem someone talking about little black rubber peices below the S/C. I also didn't see any of these when I took it off either.

 

no dont have any pics and the little rubber pieces may have stayed in the supercharger bolt hole when you removed it

 

Anyone know the part # for the black rubber spacers? I checked all the hoses and the gasket was seated properly. made sure all the hoses were good, so Im guessing me missing these 2 black rubber peices is causing it? However I can't find them on CED.

 

I checked the gasket, it was good and set. Cleaned the TB, rechecked all hoses and I still have the problem. It sounds like its missing, like a foul plug, so I checked all the plugs, they are good. I got a CEL yesterday for a misfire in Cylinder 3 and cleared it as random and hasn't happened again. But the exhaust just sounds terrible. like duh duh duh...duh has that erradic step in it. And its leaking quite a bit of what looks like water or carbon. Hard to tell since any water coming out of the exhaust will end up black.

So any other ideas?

 

if you are running the ottp tune it has a slight misfire at idle. mine is the same way. i asked about it a couple days ago and a couple people that have there tune also have the same situation. if you know someone with hp tuners they can look over your tune and fix it. thats my 2 cents.

 

Well i'm not an ss, nor do i have the ottp tune but i am have been having similar issues. I have a turbocharged 2.2, i'm tuned by trifecta. But i was having a random surging issue at idle, sometimes it would be normal, when normal it would idle at 800rpms. In the process of trying to fix my surging issue, i took my throttle body off and cleaned it, put it back on, then it started idling at 1100 rpms and still had the surging issue.
Long story short, we were able to tune out the surging issue, but it is still idling above normal. Today, i replaced my intake manifold seals and throttle body seal, i also replaced my throttle body with a new one from gm, and i'm still idling at 1000 rpms. So i'm just gonna drive it and see what happens, no solution, but i feel your pain, lol...