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Hey all,

My car is currently at my tuners with a rather annoying problem... The car was there to be tuned after I fitted a Plazmaman intake plenum and 72mm throttle body, as well as ID1000's, HKS fuel rail, -6 braided fuel lines, Sard FPR etc. So it's undergone some pretty major modifications.

It also had some problems with the NIStune, so I bought a Link G4 plug in which has now been fitted and it is up and running and it seems that it only has the one problem left, in that it wants to rev itself to redline as soon as you start it. The boys have tried blocking off the IAC valve as well as the throttle body, but it is still doing it, so obviously there is a pretty major air leak somewhere. They are currently trying to find it by blocking off hoses etc, but I was hoping some brainstorming may be able to help.

The issue is, it's very hard to find an air leak when you can't start the car... We would try the smoke or throttle cleaner tests, but when the car is smashing limiter within a few seconds of starting, there isn't much one can do. So I just wanted to find out what sort of air leak could cause the car to do this? I mean, surely it takes a substantial amount of air to make the car rev so hard, so it wouldn't be just a small hose or something? We reused the upper plenum gasket when we installed the plenum as it was in perfect condition, but would a leaky plenum gasket do this? What else could leak such a large amount of air?

Thanks for any help, I understand it could really be anything and playing e-Mechanic probably isn't going to get much done, but I'm desperate at the moment...

Cheers,

Martin.

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Get a piece of stainless tube the same size as your pod fitting, weld one end shut, drill a hole in that end, and weld in a air compressor fitting.

Should take a fabricator about 10 mins.

Take off pod, install device, and then hook air compressor hose up.

Listen to air whistling out of somewhere with the car shut off.

Edited by The Mafia

Yeh I've tried a similar idea before when I had a vacuum leak, but found the whistling from the air compressor was way louder than the whisteling from any air leaks, so it didn't make it any easier to find.

Still worth a go though.

what mafia said, you want to regulate the pressure though, you dont want to be pumping 100psi into your intake. a valve from a car wheel/tyre works well and just pump it up like a car tyre.

if you cant find it with soapy water, try and get some smoke into the intake and see if you can see where its coming out from.

what mafia said, you want to regulate the pressure though, you dont want to be pumping 100psi into your intake. a valve from a car wheel/tyre works well and just pump it up like a car tyre.

if you cant find it with soapy water, try and get some smoke into the intake and see if you can see where its coming out from.

Yeh this is what I've got and tried in the past. I'll give it a go if the workshop can't find anything. Though I'm starting to think that for such a major leak to occur, it is most likely to be the new plenum not sealing, maybe I didn't get the plenum to sit flat on the runners properly :(

Thanks guys, I'll see what I can do.

That's not true, the new ECU was supposed to arrive today or tomorrow, but instead it arrived last Friday!! That's a win, right!?

Right?

Lol yeh, I'm very lucky my tuner doesn't want to charge me anything for the car being there for so long. It was only meant to be a quick retune, it's been there for a month now :/

hey i had the same problem when i did my Plazmaman plenum, you need to put gasket gue on both side of the plenum gasket and tighten the bolts i know its a bitch to get to lol it took me 3 hours to do them.

I wouldn't use Gasket goo on it, use Loctite 515 (also dont use much of it, only a thin 1mm bead) its a much better product for manifold type seals, atleast on the intake side of things.

Edited by 51NNA

I used one of the Loctite sealants, can't remember which one. The correct one for the application anyway.

It had nothing to do with anything like that lol.

Blue maxx? I used threebond on my intake manifold gasket, just a thin layer and has been all sweet so far

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