i am looking to buy a turbo2 that has a problem cutting out around 3500 rpms. when you drive nice and easy it drives fine, as soon as you give it 50% throttle it cuts out. which made me to believe the secondary injectors aren t working properly. does anyone have some solution to the problem or any helpful ideas. of course the first step would to make sure the injectors are plugged in properly, but i have no ideas after that. any suggestions would be greatly appreciated. thanks.

 

If you mean that it totally dies when you give it more than half throttle, it means it needs a new ECU. I had an 86 base that did that; it'd rev fine, but once you gave it more than 50% throttle, it'd die; you could stomp on it at idle and it would die. You could rev it up to 6k rpm, give it 50% and it would die. Of course to kill it totally, I had to keep the accelerator depressed. I took the ECU apart and it was totally fried inside (burnt blue resistors and a scorched PCB under them).

If it's just hesitating really badly, plan on doing a complete grounding job as well as a fuel pump re-wire and replacing all the vacuum hoses. To test the injectors, swap them (primaries and secondaries). To see if the secondaries are turning on, either use a multimeter that tells duty cycle (DC) or just hook a regular multimeter and look for a voltage increase. Aside from that, test all the sensors/electrical devices (coils, CAS, BACV, AWS, ect..), and check fuel flow/pressure.

 

thanks for the suggestion.
what is all involved with rewiring the grounding? what ground wires are you refering to?

 

Doing a "ground job" is pretty easy. If you have a decent soldering iron, flux (makes copper/aluminum "sticky") or solder with flux (most of it is), then you'll be able to do this. Read this thread: https://www.rx7club.com/showthread.p...hreadid=179899

As some pointers, Don't get frightened by the #'s for the pins on the ECU. Really, just all the wires that are already bundled together about 6" up the harness (the one with 2 plugs) need to be grounded. I HIGHLY suggest you get pin 2C. Throw plenty of solder on the factory "crimp" connection(s). If you don't have a nice pair of crimpers, solder the wires inside the ring connectors. They're grounds, so if the plastic melts a little, it doesn't matter. Make sure to tape everything (the actual solder joints) nicely when you're done.

I noticed, however, that when I had both the ECU and the Boost sensor re-grounded that it somehow managed to make my problem worse. How, I still don't know (the ground was still reading 0ohms with or without the tertiary ground).

Best rule when doing something that seems hard: Keep it simple.