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rx-4
01-22-2010, 07:50 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?

Ender
01-24-2010, 12:38 AM
What's the number on the ECU you're using? And what wiring harness are you using? Give us more details about the swap. Like is it a fresh rebuild? If so, what was done? Any porting work? Injector size/shape/color is important. You mentioned the rear plugs looked brand new, that would make me suspect the rear injectors aren't opening. Rotaries don't burn terribly clean, especially if they're not running right, so if they're clean I'd be at least suspicious. It's also possible you have a faulty TPS and or bad electrical grounds, those are common problems.

vkjrocker
01-24-2010, 01:29 AM
hmm almost sounds like my problem... good luck man. i'm still trying to figure out mine :\

RETed
01-24-2010, 04:48 AM
Get a competent mechanic / shop to sort out your problems.
These "backyard" swaps ruins these cars, and you're in over your head.

I couldn't read past the first few lines, cause of no punctuation and bad grammar made my head hurt...


-Ted

N.RotaryTech
01-24-2010, 07:04 PM
Get a competent mechanic / shop to sort out your problems.
These "backyard" swaps ruins these cars, and you're in over your head.

I couldn't read past the first few lines, cause of no punctuation and bad grammar made my head hurt...


-Ted
This better?
OK i got a 91 Rx7 n/a with a turbo swap.
I was having a problem with the injectors not firing.
I 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 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 let 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?

Its funny that I bothered to do that.

RETed
01-26-2010, 08:45 PM
This better?

Its funny that I bothered to do that.

Lame attempt at capitalization, but your grammar still is poor.


-Ted