Well I have this strange hissing sort of sound coming out from under the hood at 5800 rpm up to redline and throttle position does not affect it at all. If I get on it hard it does it and if I slowly creep up to 5800 it starts reguardless. I just don't get it. I just rebuilt about 1000 miles ago and it's been running great, no CEL's or anything out of the ordinary. I just started running it hard and this sound has come out of nowhere. It never did it before the rebuild. It almost sounds like air hissing, but it is consistant in every gear at 5800 rpm. I am stumped, the only thing I can think of is the tranny, but I don't know what it would be. Please help me out. TIA
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

hissing sounds are usually vac leaks. are you turbo? maybe a boost leak when your getting on it hard?

I'm at 8.8:1 comp and plan to turbo really soon, but right now I'm N/A. Would a vac leak only sound at 5800?? I hope that's what it is. When I idle, my vac is only at like 10, so you think that's it?
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

You sure its not the airfilter?

yes, I am positive it's not my air filter. It only does it from 5800 to redline. I have had the throttle at different positions from 5800 on up, and the sound didn't change at all, it's just a steady hissing coming out of the front of the car. I thought it was the intake at first also, but it isn't. Any other thoughts?
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

your vac at idle is 10? it should be like 18-21. maybe you just cant hear it ayt idle and only when your getting on it. i would check every vac line possible.

Well damn, I checked every vac line everywhere and just can't seem to find this stupid vac leak, I still am reading 9-10 vac at idle. What the hell?? Any places I might be missing? I just don't know where else it would be. I guess this being the only problem during rebuild is a blessing. Help me out.
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

get some carb cleaner. then start your car and spray the cleaner around every vac line possible, if the rpms seem to go up a little while your spraying, thats where your vac leak is. try that and then come back.

Don't overlook your TB gasket. My 95's leaks and it sounds like a really small turbo when I get on it at around 4K, and up higher when I am not at WOT.

Originally posted by marius
Don't overlook your TB gasket. My 95's leaks and it sounds like a really small turbo when I get on it at around 4K, and up higher when I am not at WOT.

anf the orings on your injectors :)

Okay, vac leak is no longer my worry, I know I have a vac leak, but am still narrowing it down, (I havn't had too much time to look for it.) Here's what I have figured out, when It's in 1st 2nd or 3rd gear, at about 5k rpm to redline, the hissing sound occurs, it's starting to sound more and more like a hissing sound, but more like metal. I had my car in the drive way in neutral and reved the motor up to 5k rpm and never made the sound, so I am coming to the conclusion that it is the Spec Stage 4 that I just installed 700 miles ago, or it's something making noise only when the car is under load. Anyone have a Spec stage 4 that makes that kind of sound at about the same rpm? It doesn't matter what the throttle position is when it's at 5k rpm, it makes the same noise in every gear, in every throttle position. I am stumped and pissed if I have to take out that clutch. When I did my rebuild, I never took the tranny out, and it never made this sound before. Thanks for all of the replies so far and TAI for anymore help (which I really need.)
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

Plus, the metal hissing sound doesn't get any louder or change pitch at all, it's steady and is the same sound from about 5800 rpm on up to redline. HELP!!!!!
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

I think its a sound quite a few of us get. It comes from the intake and goes away when you put an exhaust on. I know it doesnt make any sense at all but thats how it is caused im told. And the sound makes me sound like im turbo'd I cant say how many times I have been asked if i was boosted. Especially by fucking ricers. I usually tell them yea im boosted on a 14B with a 1st gen bov and I dont vent it. Don't worry about how many lbs Im boosted on. lol.. I hate ricers so I tell them that to shut em up. And I never race so I don't have to worry about people knowing its a lie.

I have a full exhaust system in my car, any other ideas? It never did this before, and I had the full exhaust then too.
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

Anybody?
~Jeffo


Hey, have you seen my tail lights? Yeah, well get used to looking at them.

Exhaust leak, not a massive one. I have the same problem, mine comes on after 4000rpm. Sounds almost like a turbo spool, gets the ricers all the time.