[b][i][u]wen my car starts runing and the boost kicks in starts misfiring or seems to chug . when im running it at hy rpms. can anyone help me with my problem? thanks...

 

Boost leak? Pressure sensor?

Also, you might want to find a way to run a spell check on your posts. You come off ignorant.

 

my bad

 

Have you done anything to car recently? How many miles on the car + any mods?

 

yeap this>>>> intercooler,intake,no emisions.

 

Yikes. That makes me think it is a leak somewhere. How does it idle? Check all your intercooler sleeves and make sure there are no leaks. Make sure your MAF is plugged in. Double check all your rats nest removal stuff. Maybe a block off plate isn't tightened all the way.

If you have an air compressor, I have seen people rig up a PVC pipe to the intake, and pressurize it, then listen for leaks.

Also, I think there is a fuel cut built into the car. I don't have a TurboII myself, so I am unsure. I have read about people installing a FCD to counter this. Might want to check into it.

Good luck.

 

s4 or s5??? swapped??? or regular TII? sounds like apressure sensor issue. if it is a swapped turbo and you are using the NA pressure sensor it will do this

 

s5 pressure sensor is a N370..

 

So no emissions = no cats?

You might be hitting boost creep. Some kind of FCD should be on your shopping list soon.

 

What is FCD

 

Fuel Cut Defencer got it...

 

If your hitting boost creep the simple solution would be to port the wastegate.

If you drive the 7 carefully can you get it to go into the high rpm range without casusing the problem?

 

yep i can drive fine with out making boost on it. Everityng starts wen wen boost kicks in....

 

The stock boost gauge isn't going to be accurate. Get an aftermarket gauge so you know what boost level your at. Might as well port the wastegate cause it has to be done sooner or later.

The quick fix now could be to put on your stock intake and see if that helps with fixing the problem.

 

your blowing up your engine.


no exhaust emissions means you are boost spiking, means your runing way too much boost, means you not tuning for it, means your crapping out your engine.

 

Exactly. He's hitting fuel cut because it's boost creeping. The rear rotor must be loving all the abuse it's been getting.

DO NOT just buy an FCD and think it's fixed. You need fuel, fuel control & a ported wastegate. And yes, you can search for this info.

 

okok so i need to tun the car and what else

 

It's not that easy...you cant just tune your car.

Assuming the motor is stock besides the obvious no emissions and intake, you can get away with a wideband for now and air/fuel controller. Here's what I invested in right off the bat when i got my T2 motor back from rebuild:

-Wideband (to read air/fuel ratios)
-SAFC (to cotrol A/F ratios)
-FCD (to make sure you keep fuel)
-Boost gauge (to read boost under full throttle)


Once you have purchased these, which will cost you anywhere from $400-$700, you can at least get to safely run stock boost for daily driving. Once you get a bigger intercooler, injectors, turbo, etc you should invest in a full stand alone EMS... like: Apexi Power FC, Greddy E manage, Mega squirt, Microtec, haltec

 

All you have to do is port the wastegate and run stock boost for now! This will allow you to drive the car hard while you figure out how you are going to upgrade.

 

something like this http://www.aaroncake.net/rx-7/s4wastegate.htm

 

YES! Even though that is an s4 turbo the s5 is pretty much the same except you prob don't have to make a new flapper door.

 

What rpm is this misfire happening?

 

2000 +

 

Does it happen only above 4k? or does it happen if you jusr floor it?

 

yeap wen i floor it