LS6 install and now a hissing noise?
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LS6 install and now a hissing noise? I installed my LS6 intake yesterday w/o a problem. Did the !AIR/!EGR bit with block-off plates. I know the vacuum line on the back of the intake is on, as is the sensor connetion. The brake booster line is fine. While the motor runs, it sounds normal. When I shut her off, I get a somewhat soft hissing noise coming from the passanger side of the motor, towards the rear corner. I'm lost, I couldn't find any hoses that were left layin around. Any ideas? I'm pretty sure its some sort of vacuum line but could have no idea which one, as all the ones that I disconnected are already back on. TIA - Travis
i'm in the middle of the install myself, but my car is running real rough and popping after the install, i know most people are saying my intake might not be seated properly, maybe its the same thing with yours?
my friends '00 camaro does the same thing and its never been taken apart. Runs fine also. We sprayed carb cleaner all around it to try to find the vacuum leak but it never idled up. We don't have any more ideas either.
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Good call John. I'm cyphur's brother, helped him with the install, and he found out that the top air vents inside don't work, so we figure that's the hose that isn't hooked up right. Anyone know exactly where that hose is?
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Originally Posted by John_D.
maybe the small hose that goes to the inside for the hvac controls?
John_D i think you hit it right on the head. i drove the car back down to fort hood(did the work in dallas), and never turned the AC on. turned it on today, and presto, no ac in the dash(works on the feet tho). which hose are you referring to? have a feeling thats exactly the problem. can anyone tell me if its possible to discern this hose from the rest w/o taking the intake back off....my hands are already looking like shredded meat from the install(forgot to file down the block after i took the EGR mounting bracket off, and never did file down the posts that keep that plastic lip on at the bottom of the windshield). Don't wanna have to take the intake off again lol. BTW my car idles fine.....but you should check your brake booster vacuum hose, i know i forgot to check mine the first time and it barely ran, had to gas it to keep it runnin, but i had forgot to re-connect it...now it runs perfect.
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well i traced some of the tiny hoses, and found one unattached. it was over there the air junction sat, on the drivers side. i hooked it back up, it hooked into a little sensor that is on a bracket that attaches to the intake(one of two on each side). however there is still a connection open, and still no ac controls. i haven't been able to get way back behind the motor cuz even after sitting for an hour and a half in the texas sun the engine compartment stays in the triple digits. i'm starting to run out of ideas, i checked as many of the small hoses over near the ac box on the passanger side of the motor, where the hoses go thru the firewall. ANY IDEAS? i'm about to just drop the motor out the bottom and figure it out lol. its that f_cking hot down here, at least in bdu's.
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Verdad Gallardo on the back of my ls6 intake (i just did the install) there were 2 pcm connections and a spot for a small hose to go on, is that hose connected? Thats the only one i had to remove to do my installation, i double checked mine before bolting the intake down and it was good and tight, and whala my A/C works excellent. Not sure according to your post if thats the hose you reconnected or not? It's hard to reach the one on the back of the intake with it all back together, i just went out and tried, i dont see how you could connect it with out getting some room back there (moving intake) It's a pain to get in the rubber connection. good luck 
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yea, your talking about the little connection under the sensor connection. that is a PITA for sure. i thought i had it on there, but now that i think about it, its about the only connection that is over there that would have had the chance to come undone. i'll have to check it tomorrow at 5am before PT b/c thats the only time of the day the engine will be cool enough to go near 
same problems here.........!!!!!this is weird plenty peeps swapping those cheap LS6 intakes......!!!!! I'm in the same boat no A/C vents.......guess I can check the rear hose of the intake but I thought it was on good maybe the hose is tore like the front 1 in my car. Hope we all can figure out the solution for the A/C fosho lets see who finds it FIRST!!!!!!!!! lol...Let ya all in if i do.....
Last edited by 2000Z28M6; Jun 4, 2004 at 10:06 AM.
I bought an LS6 intake to try and when I went to bolt it on, found that it was warped! Could have probably tighten it down and gotten by, but I sent it back. Was not impressed with the quality of the LS6 Intake!
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Well I got my LS6 intake from MorePerformance, and it was in great condition. Extremely clean, not warped at all, and the gaskets were still in pristine condition. Guess I lucked out. Anyhow like I said I was going to do, I got under the hood this morning at o dark hundred(5am for the civilian types) before PT and tried checkin out that little hose. VIOLA!! As I had thought, I got the rubber connector on, but what I didn't realize that somehow as I put that on, it detached itself from the plastic vacuum hose. So in pitch dark I found myself kneeling on my battery and strut tower tryin to finagle that thing back on. Got that all squared away and now my a/c works perfectly again. I appreciate all you guys' help with this, now I can cruise in comfort again!!
cyphur are you talkin bout the big hose that goes to the back of the intake? Is that what fixed the vents? I checked everything I could find and the only other hose that is not plugged in is the on that goes into the harness from when I removed the AIR system and that one shouldnt matter rite? If I have to double check the one on the back of the intake so be it but I touched it and it felt like it was on there, but I guess you cant really tell unless u really get back in there. Help if you can.
Last edited by 2000Z28M6; Jun 3, 2004 at 02:53 PM.
I think I figured it out, The LS6 Intake I have is off a Corevtte and it does not have the little fitting for the vaccum for the vents. So I now have to finding vaccum from somewhere else and fix it by tapping it with a T-fitting. I think this will do the trick let you all know lata.. Just wanted to make things clear, but this is what I'm referring too.
Last edited by 2000Z28M6; Jun 3, 2004 at 04:43 PM.
Yep, that will fix it.
I have the Weiand intake, which also doesn't have the AC vac line provision.
I "T"'ed into the fuel vapor vac line on the driver side of the intake, and everything works peachy.
Bad30th
I have the Weiand intake, which also doesn't have the AC vac line provision.
I "T"'ed into the fuel vapor vac line on the driver side of the intake, and everything works peachy.
Bad30th
Sorry I don't have the best pic in the world handy, but here's the idea... This is when I still had the cough, blue engine loom.
At the driver side of the intake right behind the TB there's a vac line that extends to the fuel evap. Just "T" into that and extend the vac line from the pass side under the TB and into the "T" fitting :
Hope this helps !
Bad30th
At the driver side of the intake right behind the TB there's a vac line that extends to the fuel evap. Just "T" into that and extend the vac line from the pass side under the TB and into the "T" fitting :
Hope this helps !
Bad30th
Last edited by Bad30th; Jun 3, 2004 at 05:01 PM.