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Help Help Help 48kw

shotter

By shotter,
in Engines & Forced Induction

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shotter Rising Star

shotter

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Ok i took my car in to get dynoed and tuned today and it was going fine and making about 180kw. Then during a run it made a loud popping noise and started backfiring. then it kept backfiring as you back off the throttle. and The car only made 48KW. Basically we tryed a lot of things to find the problem. the adj valve timing solinoid wasn't working for a little while, then it started working again. The AFM decided to go to 5.1V and the car wouldn't start. After some searching we found a cracked solder track. Fixed that and the car started but still no power. Tryed different AFM. Does anyone have any idea's or have been thought this problem before?

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Cjmartz2k Proficient

Cjmartz2k

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Still sounds like a boost leak problem. Maybe split grommet or blown gasket somewhere. Do a boost leak check--quick, easy, and next to free, just to eliminate that as a potential problem. Maybe that's not it, but that's where I'd start.

VB- Veteran

VB-

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Still sounds like a boost leak problem. Maybe split grommet or blown gasket somewhere. Do a boost leak check--quick, easy, and next to free, just to eliminate that as a potential problem. Maybe that's not it, but that's where I'd start.

its making boost thought, even if there is a leak, its still getting 12psi or whatever hes running in the plenum, should be making more than 48kw.

the only powerloss from a boost leak should be the drop in effeciency as the turbos spinning hard to make the required boost at the plenum, due to the leaking air somewhere else. unless theres something im missing?

shotter Rising Star

shotter

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The air ratio's are around a normal level. So nothing bad going on there. We thought it could be a timing problem when the adj valve timing stopped working. So we pulled the front cove off and pulled the trigger wheel off and noticed that the key that sits inside the cam and also the trigger wheel had snapped off. But we didn't think that was a huge problem because we checked the timing and it was ok. The one think that did pop out was the PCV hose and grommet. The grommet split. So we were able to put a bigger rubber hose in the hole and slide the PCV valve into it. It doesn't sound like it's leaking. But i dont know if it's venting pressure into the top of the crank case. And i guess it could even be the std ecu. it's not logging any fault codes but i dont know if that is causing it. Another idea i had and i really dont wanna think about this one is could i of melted a piston?

Ultimategtr Proficient

Ultimategtr

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It shouldnt be any internal damage i dont think.

I suppose it doesnt make any funny noises when you drive/boost?

Can you post up the last dyno run before it "blew"? It could still be a boost leak somewhere, but the turbo would be working harder to "make" 12 psi or whatever you boost. What was the peak boost you had?

Just a wild and noob suggestion - have you reset the ecu? since you said youre running the stock ecu, and if thats the case, able to swap ecu's or even the CAS with a working one off your mate?

You say that its boosting ok, does that mean you can "feel"the power as before? or you feel the turbo boosting but you dont go anywhere, is that the case?

Whats the timing set to?

shotter Rising Star

shotter

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I dont have any dyno sheets. and it is still on the dyno. You can hear the exhaust note change at about 3000 rpm, it just goes really flat.

We have pulled the ecu out and tryed running the car with another r33 ECU but the car wouldn't turn off with that one connected. So we decided not to do a run with that connected. And it does make a ticking / rubbing noise at idle. which went away when we loosend off the bolts on the timing wheel /trigger wheel / destributor... whatever you call it.

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