Hello. I have a JDM S4 TII engine and tranny in my GSL-SE. I got it to run today. It fires up and idles great at about 500rpm. The problem is when i rev it past about 1200rpm, the motor starts to cut in and out. I can hold the trottle still and it will rev, then cut out, then rev,..... I have an Air/Fuel meter and it goes blank when the car stumbles, then comes back when it revs. The car has an 1987 TII ECU. I have removed all the emission system including the rats nest. I can rev it between the cuts up to 4000rpm with about 1.5psi of boost. Anyone have any ideas?

 

All I got for you is that it is an electrical issue.

 

there could be a couple of issues, you said idles good but you cant tach it up? could be a bad coupler between the mafs and the throttle, bad tps or out of adjustment tps, ignition breakup (kinda a strech there) or injector issue. s4 jdm does it have the high or low impedence injectors? if they are low do you have the resistor pack installed? the a/f meter is it a wideband or narrow? if its narrow its pretty much useless. i am not sure what you have for a setup but if you are using a stock turbo inlet pipe (tip) they crack regularily. you may want to do a boost leak check.

 

I have a S4 non-turbo resistor pack On the sensor, I have a $50 Cyberdyne unit. I am also using a the tps of my GSL-SE engine.

 

what's your fuel pressure?

 

I haven't checked it. I installed a Walbro 255lph unit.

 

Check the wiring and harness around the CAS, and try swapping in another CAS.

 

I don't believe it is spark issue, rather a fuel issue. If the CAS was bad, I would be losing spark too, right? Could a bad boost sensor be my problem or is it still most likely my GSL-SE TPS not being set up right.

 

Check the TPS...


-Ted

 

TPS is a good one too.

The CAS controls basically the entire fuel injection system by telling the ECU the position of the engine. All kinds of weirdness occurrs when it's bad.

 

Just swapped back in the TPS that came with the JDM motor. The engine had a twin TPS, but I only used the one sensor. The car will now rev out, but still will bounce about 200rpm while the throttle is being held still. Maybe the TPS is out of adjustment?

 

If you swapped the TPS, you must go through the adjustment procedure.

 

where can i find the adjustment procedure????

 

Factory Service Manual.