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rx-4 07-30-2009 05:54 PM

OK i got a 91 7 n/a with a turbo swap i was having a problem with the injectors not firing tried a lot of things and finally i put a different engine harness on and i got them to fire.i tried to start it and it took about 15 min before it finally started and when it did finally start it if i let it get below 2k rpm it would start running rough and then it would die. so i reset the timing after i did that i started it up and then when it hit about 3k rpm it would just cut out and sound like i turned the key off and as soon as i let off the gas it would start up running again. so i warmed it up and adjusted the TPS and it ran fine. i left it idle for like 45 min and just watched for leaks tweaked the timing and checked for vac leaks didn't see any problems so i tried to drive it. and as soon as it wants to try to start boosting it just cuts out and sits at around 1.3k rpm for a few seconds and then dies unless i let off the throttle and if i just feather the gas and keep the manifold pressure below -0- it will drive fine i got going fast enough to get into second in less than a half a block. i pulled it back into my garage and turned it off and left it sit for 5 min and went to start it back up and it wouldn't start so i pulled the plugs and the front rotor plugs were black and the back rotor plugs still looked brand new. i cleaned the plugs and put them back on and it started up. i used my timing light to check if all the plugs were firing and they are. so i checked the timing again and it was about 25 degrees advanced now so i set it as good as i could (about 5 degrees advanced) and tried driving it again and nothing changed. i have an extra ecu and figured i would try swapping them to see what happens and all my problems started back up again it wont run above 3k rpm the timing went to about 30 degrees advanced again. any ideas on what to do now? possibly a bad cas, blown turbo, and/or stuck waste gate? also my boost solenoid and those other 3 vac sensors will start clicking sometimes with the key on. possibly messed up wire? anyone got any help or direction for me?

rtrypwr98 08-01-2009 08:15 AM


Originally Posted by rx-4' post='924935' date='Jul 30 2009, 05:54 PM
OK i got a 91 7 n/a with a turbo swap i was having a problem with the injectors not firing tried a lot of things and finally i put a different engine harness on and i got them to fire.i tried to start it and it took about 15 min before it finally started and when it did finally start it if i let it get below 2k rpm it would start running rough and then it would die. so i reset the timing after i did that i started it up and then when it hit about 3k rpm it would just cut out and sound like i turned the key off and as soon as i let off the gas it would start up running again. so i warmed it up and adjusted the TPS and it ran fine. i left it idle for like 45 min and just watched for leaks tweaked the timing and checked for vac leaks didn't see any problems so i tried to drive it. and as soon as it wants to try to start boosting it just cuts out and sits at around 1.3k rpm for a few seconds and then dies unless i let off the throttle and if i just feather the gas and keep the manifold pressure below -0- it will drive fine i got going fast enough to get into second in less than a half a block. i pulled it back into my garage and turned it off and left it sit for 5 min and went to start it back up and it wouldn't start so i pulled the plugs and the front rotor plugs were black and the back rotor plugs still looked brand new. i cleaned the plugs and put them back on and it started up. i used my timing light to check if all the plugs were firing and they are. so i checked the timing again and it was about 25 degrees advanced now so i set it as good as i could (about 5 degrees advanced) and tried driving it again and nothing changed. i have an extra ecu and figured i would try swapping them to see what happens and all my problems started back up again it wont run above 3k rpm the timing went to about 30 degrees advanced again. any ideas on what to do now? possibly a bad cas, blown turbo, and/or stuck waste gate? also my boost solenoid and those other 3 vac sensors will start clicking sometimes with the key on. possibly messed up wire? anyone got any help or direction for me?

Did you replace everything needed to make it a turbo car. Map sensor turbo AFM, ECU etc?

rx-4 08-04-2009 04:01 PM


Originally Posted by rtrypwr98' post='925052' date='Aug 1 2009, 08:15 AM
Did you replace everything needed to make it a turbo car. Map sensor turbo AFM, ECU etc?



yes everything is from a turbo car. the only thing that is from a non-turbo is the body harnesses everything under the hood is turbo.

13bturbofc 08-04-2009 07:35 PM

sorry to say, it sounds like the front rotor has seen better days...if you pulled the plugs and the front was nasty looking and the rear was clean that is a tell tale sign that there is a problem with the front rotor. have you done a compression test yet? what you can do is just remove the front leading plug and unplug the CAS so it dosent start, your listening for 3 strong and even compression pulses. then put that plug back in and do the same with the rear. If the pulses are weak or non existing then you have some blown apex seals. What probably happend is your harness shorted out and an injector wasnt firing causing it to run lean and blowing the motor.

rx-4 08-09-2009 03:12 PM

i tested the compression and the front and rear rotor read right around 90 all around. and the thing with the injectors is they wouldn't hit at all before so it wouldn't start. also it always smells rich and it floods out sometimes (rear rotor plugs usually drenched in gas). i checked the spark and each plug gets a nice spark.

ryosuke_fc 08-09-2009 09:46 PM

Hey man, I don't have any sage advice for you unfortunately. However, I just swapped an S5 Turbo JDM motor into my '87 TII and I'm having the same problem as you. The car won't stay running on its own and anything about about 3k rpm is really rough. So far, I've only been able to keep it running long enough to get the timing "close" to right. The timing seems to stay where I set it on mine though. Did you do the resistance check on your CAS? IIRC, it's supposed to read ~ 1 ohm across each pair of wires. If you have any luck, please update this thread. I'll do the same.

rx-4 01-13-2010 02:40 PM

still having these problems anyone have any advice?


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