What makes my car screech, jerk and then blows apart my intercooler?

[ixi]

First off my car was running great for two years before this developed, no new hardware was introduced to produce this problem.


Oooookay, so kind of a long story but I've been trying to track down a major studder/shudder/jerking/stumble/boost leak/limp mode/car runs like shit/ problem for about 3 months now.

It developed when I was trying to get up a very snowy, slippery road and I was spinning my wheels like crazy and was in 3-4k rmps for about 30 minutes. Well after this my car started stumbling/studdering/jerk...etc...whenever I went over 8 psi or so.

When I get to about 8 psi or so it just shuts down, it makes a screech along with a sputtering gasping noise then the boost just shuts down.


I've tried EVERYTHING........

Things ruled out

N75 (swapped out with a new one)
accordion hose (new APR hose)
new spark plugs
NO boost leaks (boost tested and plugged up several small leaks)
no maf problems (unplugged it and it runs worse without it)
no cat problems (hi flow cat installed)
not a DV problem (switched out with another, no change)


Sooooooo, I decided to put in the red spring (instead of the yellow) into my Forge DV to see if there was any difference. Well I was pushing it a bit to see if there was any difference and it was acting the same as before when I hear a loud POP! I figured I just blew one of my intercooler hoses, so I limped home slowly.

Come to find out I blew apart the lower portion of my stock intercooler. What the hell? Was there a blockage here, a leak?

Here's a pic, it's where the hose connects to the intercooler from below. What could have caused this? (I know it's filthy, I keep destroying belly pans)






What is wrong with my car?

99 AEB 115k
k04 giac pc16
n75j
kenitic motorsports exhaust manifold
turbo back brullen exhaust, hi flow ghl cat, tt downpipe
lightweight crank thingy


I just replaced my intercooler and my boosting problem remains the same. Now I'm scared of boosting at all because I don't want to blow another ic apart.

Why do you think that happened in the first place? I've tried just about everything and I'm starting to worry my turbo could be bad after 30k. My wastegate has no play, the turbine spins freely with no blade damage. If I feather the throttle it will boost somewhat normal up to 20 psi.

Just to describe again what it's doing - when I punch the throttle it starts to screech around 10-14 psi, then it will jerk hard and boost just shuts down. No codes, and I don't have a laptop to log anything, that might have to be my next purchase.

So what causes a screech and jerk and also blows apart your ic?

Please help, I miss my car.

[Euro-Tuner]

your diverter valve isnt seized? even if it was I dont see that causing half the symtoms you describe

[ixi]

your diverter valve isnt seized? even if it was I dont see that causing half the symtoms you describe

No, dv is fine, just greased it up. I've also swapped it out with another and the problem is the same.

[ixi]

Well I just replaced my boost gauge since it was acting a little strange and I think it was bad. Now when I my turbo "screeches" I see a very fast spike to 25+ psi, not good. This wasn't reading on my other gauge. Strange.

So I guess thats why my IC blew, I'm just lucky it wasn't my motor. So is this a wastegate problem?

[Poopie]

you shouldn't be running a stock IC anyways with PC 16. Sounds like a blown turbo to me.

[Monk]

when I punch the throttle it starts to screech around 10-14 psi, then it will jerk hard and boost just shuts down.

Misfire.

So is this a wastegate problem?

This was in your original post . ..

My wastegate has no play,

[mike-2ptzero]

Sounds like it could be your wg just seized shut causing you to over boost. Have you tried bypassing the N75 valve allowing pressure to get right to the wg actuator? Doing this will cause the wg to open right away and you should only see no more then 5psi, if you get more the wg isn't opening like it should.

[ixi]

Sounds like it could be your wg just seized shut causing you to over boost. Have you tried bypassing the N75 valve allowing pressure to get right to the wg actuator? Doing this will cause the wg to open right away and you should only see no more then 5psi, if you get more the wg isn't opening like it should.

I was just reading about that in another post. So I string some vacuum hose from nipple to nipple right? I'll go give that a try, might take a wile.

[mike-2ptzero]

I was just reading about that in another post. So I string some vacuum hose from nipple to nipple right? I'll go give that a try, might take a wile.

You can do it that way or just remove the 2 lines from the N75 valve and connect them together with a vac line adaptor. Either way will work since you just want to get pressure directly to the wg actuator.

[Militant-Grunt]

How are you running Pc-16 on a stock intercooler..?

[ixi]

You can do it that way or just remove the 2 lines from the N75 valve and connect them together with a vac line adaptor. Either way will work since you just want to get pressure directly to the wg actuator.

Ok, much easier, do I need to plug up the nipples?

[mike-2ptzero]

Ok, much easier, do I need to plug up the nipples?

yeah you will want to loop the 2 nipples together so that unmetered air doesn't get into the TIP, but if you dont plan on running it this way for more then just a quick test it should't be a problem.

[ixi]

yeah you will want to loop the 2 nipples together so that unmetered air doesn't get into the TIP, but if you dont plan on running it this way for more then just a quick test it should't be a problem.

Ok, just took her for a drive and with the two nipples connected there is no change. It spikes to 25+ just the same. Same jerk, studder and shudder noise.

So is my wastegate not opening? Is the turbo shot? Shit.

[Poopie]

turbo sounds shot. any smoke coming out of the exhuast?

[mike-2ptzero]

Well if it is making 25+ psi the turbo is not shot, but the wastegate is not working like it should.

A dead turbo will not make any boost.

[ixi]

No smoke coming out the exhaust. It behaves almost normal until it hits 10-14 psi, then the screech and boost builds very fast until it feels like it just chokes out.


I've been reading up on wastegates and can't find much info on wastegates being stuck closed, only open.

How does a wastegate get sealed shut? If I pull my turbo can I adjust anything, pull it apart?

[audiFUEGO]

you held 3.5k rpms for 30 min with pc16 and stock intercooler?

[ixi]

you held 3.5k rpms for 30 min with pc16 and stock intercooler?

Kind of. Had to get to work. It was 0 degrees out but whatever.

Lets talk about wastegates.

[mike-2ptzero]

No smoke coming out the exhaust. It behaves almost normal until it hits 10-14 psi, then the screech and boost builds very fast until it feels like it just chokes out.


I've been reading up on wastegates and can't find much info on wastegates being stuck closed, only open.

How does a wastegate get sealed shut? If I pull my turbo can I adjust anything, pull it apart?

It just gets jammed in 1 position. I had this happen to a external wg and the boost kept going up till the ecu would close the throttle once the maf sensor maxed out.

[ixi]

It just gets jammed in 1 position. I had this happen to a external wg and the boost kept going up till the ecu would close the throttle once the maf sensor maxed out.

I know an external wastegate is different but what happened with yours? If I pull my turbo can I just wiggle it free? force it free? install a new wastegate?

[ixi]

If I take off my exhaust manifold will I be able to see the problem?

[390wheel]

are you running a stock turbo ???
if yes, i dont think the k03 or a k04 are able to blow the stock intercooler. and the ecu will go into limp mode as soon as it sees the over boost. is the car running good other wise????
no misfire or anything like that??? i think maybe some crazy back fire could do that. if you need intercooler i got one... pm me...

[ixi]

are you running a stock turbo ???
if yes, i dont think the k03 or a k04 are able to blow the stock intercooler. and the ecu will go into limp mode as soon as it sees the over boost. is the car running good other wise????
no misfire or anything like that??? i think maybe some crazy back fire could do that. if you need intercooler i got one... pm me...

I appreciate the offer but I've already installed another one. I'm running the k04 and at this point I'm pretty sure the wastegate isn't opening at all.

Now I'm looking for any info on frozen shut wastegates and what to do about it.

[Yaktizzle417]

Your PC-16 K04 is pushing so many cfms of air through the IC, it blows it to pieces.

You're murdering your car with that stock shitty SMIC.

Get a front mount immediately.

[gotaudi]

He is probably pulling an insane amount of timing without the proper cooling. I bet he isnt making any more power than an aggressive Ko3 setup.

[Yaktizzle417]

I bet he isn't making any power period..

[ixi]

I bet he isn't making any power period..

Jesus....I don't drive my car hard, a few aggressive corners and more power passing on the freeway is all I have this setup for. I've run without a fmic for two years and it's been fine. I don't need one and I'm not getting one.

How about helping out on the wastegate problem. When a wastegate is shut is it a faulty rod or is it the "flap" that's the problem.