Intercooler Problems

[rick444]

I just fitted a new justjap intercooler on my r33 s2. The car runs fine, until you reach 5500 - 6000 revs then boost drops off.

I've been told that a small leak in an intercooler pipe or join would cause this, but I've tightened them all up, and it's still happening.

Is there something else I should be looking for?

Thanks

[paulr33]

check all of the silicon joiners, make sure they are good quality silicon ones with tightened hose clamps

[SECURITY]

go around with some detergent in a spray bottle and spray it on all your pipes/joiners with the car on. wherever it starts bubbling up - thats where your leak is.

[Devils_Advocate21]

It should be in the joiners or around the clamps, invest in some t-bolt clamps they are your friend, and vpw for you silicon needs as they usually stock tripple layer stiched silicon joiners

plus boost leak can be also something else like controller bleed valve etc but start with the basics first and securitys idea should help aswell

Good luck

[rick444]

Ok I will double check all my joins, thanks for all your help.

Sounds like a great idea SECUR1TY, i will be trying that.

[rick444]

Unfortunately I still can't find a leak, I've checked all my joins, tightened them all up and tried SECUR1TY's trick. It's still losing power around 4500 - 6500. The car feels great up until then.

When it happens, I car feels a bit jerky, and i can hear this muffled/faint bumping noise. :S

When I replaced the intercooler, I had to reattach the wastegate actuator vacuum to one of the new cooler pipes using a nipple screw I bought from repco. The new nipple is a bit smaller in diameter to the nipple from the old stock cooler pipe, could this be the problem?

I've read that cracks in coils would also cause this behavior, but it seems strange that it would start happening the day after I replaced my intercooler.

I have a 3" exhaust and pod, and I believe I'm running 10psi, according to the previous owner (I don't have an electronic boost controller).

If this is definitely a joiner problem, I will have to get some t-bolt clamps like Devils_Advocate21 suggested.

Thanks for your help.

[skylinegtts]

sorry to hijack the thread,

but could there be a leak where the joins are somewhere, but there isnt a loss in boost reading from the boost gauge? i.e theres a leak but it still shows 10psi on the boost gauge (working correctly) but its really say 7psi?

[RBwhatever]

sorry to hijack the thread,

but could there be a leak where the joins are somewhere, but there isnt a loss in boost reading from the boost gauge? i.e theres a leak but it still shows 10psi on the boost gauge (working correctly) but its really say 7psi?

I've had an intercooler hose incorrectly tightened up thanks to me and it half blew off. It started to leak quite a bit of boost but it would still hit my preset 10psi. It would later on in the rev range lose a couple of psi. It would kill alot of performance also.

But although it was leaking big time it was still hitting full boost.

The only way for it to do this would be for the turbo to work harder to create the predesired boost.

So essentially the boost leak just became a massive bleed valve, without the valve bit.

[RBwhatever]

I just fitted a new justjap intercooler on my r33 s2. The car runs fine, until you reach 5500 - 6000 revs then boost drops off.

I've been told that a small leak in an intercooler pipe or join would cause this, but I've tightened them all up, and it's still happening.

Is there something else I should be looking for?

Thanks

Could have something to do with your boost controller.

What kind do you have?

[RBwhatever]

Sorry disregard my last post.

[rick444]

I've had an intercooler hose incorrectly tightened up thanks to me and it half blew off. It started to leak quite a bit of boost but it would still hit my preset 10psi. It would later on in the rev range lose a couple of psi. It would kill alot of performance also.

But although it was leaking big time it was still hitting full boost.

The only way for it to do this would be for the turbo to work harder to create the predesired boost.

So essentially the boost leak just became a massive bleed valve, without the valve bit.

I've checked all the joins though, and I don't think I can tighten them any more. I couldn't find any leaks either. Is it likely that air is escaping under a tightened hose clamp?

Thanks

[RBwhatever]

You can do a leak test.

What you'll have to do is,

1. take your pod and AFM off.

2. use a baked bean can (full) and put it into your rubber intake pipe (assuming its still the stock one).

3. tighten up the hose clamp onto the tin creating a seal.

4. Open the throttle body with a brick on the accelerator pedal, so you can read pressure on the boost gauge.

5. take a hose that is plumbed into your intake between the turbo and the plenum or off the plenum itself (you could probably use that nipple you installed).

6. Get an air compressor and pressurize the system through the hose and get someone to read the psi on the boost gauge. you only need about 5psi. you can use the compressors at the servos.

7. Listen for a leak. and use the soapy water in the spray bottle to find exactly where it is.

It is easier to find a boost or pressure leak using this method because the car is not running.

[rick444]

That sounds like a good idea, I might have to get hold of an air compressor.

So would you say this is definitely an air leak problem, rather than something do with the coils, or the new nipple?

Edited April 16, 2007 by rick444

[sky-017]

when your boosting is it making a fumbling noise , and noticable out of your exhaust? if so your probably having a misfire .... could of just started when you put your intercooler on .. and emerged when the boost was raised .. your not using a turbo tech boost controller are you? your going to need to drop to 0.8 for your spark plug gap .

also another thing to do is , block your nipple from the intercooler pipe and try run it from the bov vacume hose . if your worried about the nipple effecting how the car runs , this could be your problem .

see if these help - cheers

[RBwhatever]

Its hard to say whether it is or not.

But its good to do the test regardless to make sure there is none.

Even if there is a small leak that doesn't seem to be a problem or create any problems, IT DOES have an effect on performance.

Your essentially pressurizing the system as the turbo does, except you'll be doing it without the car running. Its easier to hear the leak when the cars not running.

I had hesitation when mine was leaking, and it was overfuelling and killing all the power especially between 4000 - 7000 rpm. And it would take ages to rev out and would also backfire.

Edited April 16, 2007 by KeyMakeR33

[rick444]

when your boosting is it making a fumbling noise , and noticable out of your exhaust? if so your probably having a misfire .... could of just started when you put your intercooler on .. and emerged when the boost was raised .. your not using a turbo tech boost controller are you? your going to need to drop to 0.8 for your spark plug gap .

also another thing to do is , block your nipple from the intercooler pipe and try run it from the bov vacume hose . if your worried about the nipple effecting how the car runs , this could be your problem .

see if these help - cheers

Yes it is actually, I'm not sure if it's related to my exhaust though, its very muffled.

I haven't raised my boost at all though. I've been running 10psi since I bought it, and it's been running fine until I replaced the cooler.

When I first replaced the cooler, I drove the car without the hose attached to the pipe, and it lost all boost around 3500, so I attached it back to the pipe, and it runs well until 5500 now. I haven't tried attaching it to the bov vacume hose yet, I might try that.

[Pauly33GTS-t]

Make sure you double check all the vacuum hoses you may have disconnected again. and make sure they are going to the rigth places.

[sky-017]

as i said try relocate the vacume hose to the vacume hose running off the BOV... but yeah you will know if its misfire because close to 6000 rpm she will drive like shes slipping and will make a very noticable noise .

open up your coil pack cover . check all the coil packs for cracks . . . if your spark plug gap is 1.5 , change them to 0.8 . that will fix the problem

mode no : ngk's , BCPRE6S ... $3.80 a plug from super cheap auto . i replaced mine the other week - made my car run so much better when i had misfiring from installing a turbo tech boost controller...

hope this helps - i think its your problem cheers...

[skylinegtts]

I've had an intercooler hose incorrectly tightened up thanks to me and it half blew off. It started to leak quite a bit of boost but it would still hit my preset 10psi. It would later on in the rev range lose a couple of psi. It would kill alot of performance also.

But although it was leaking big time it was still hitting full boost.

The only way for it to do this would be for the turbo to work harder to create the predesired boost.

So essentially the boost leak just became a massive bleed valve, without the valve bit.

ahhk.. thanks mate