fuel injectors won't go.

Driving along it on a trail and the engine quits. First plan of action was to do a CPS which did nothing. We then realized that the fuel pump wasent going so we did a jumper wire to get it going. now cranking along with the fuel pump pumping and the sparkplugs sparking it will not start. The fuel injectors dont seem to be opening its 1990 with renix auto trans. is ther diagnostic stuff or any ideas? thanks

sounds like a fuel pump to me, get a gauge on it

what controls the injector signal. could it be a bad ecu? I find i kind of odd that the fuel pump would quit and the injectors would stop getting signal at once. I will try a pressure guage and see whats going on with it.

i believe the stator/cam postion sensor in the distributor housing controls the timing of the injectors.

hmm never heard that. somthing else to check. thanks

Most likely it's fuel pressure, if the pressure tests out OK you may want to check your injector grounds. If it's getting spark the CPS and associated wiring is likely OK.
Post back up and let us know what you've tested. Cam position sensor would be low on my troubleshooting list for a Renix, my motor runs just fine with it disconnected.
The injector drivers in the ECU have been known to go bad, but if it is the injectors themselves a wiring problem is more likely. The grounds for the injectors go through a bunch of splices any of which could be loose. Where the injector harness makes the bend at the firewall is a known trouble spot for under the insulation wire fatigue breaks. Wires sometimes break under the insulation and can be a pain to find.

My 1990 quit in the same manner. I had to jump the fuel pump to drive it. Then the injectors lost signal and it would not start.

Ended up being the relay harness(that holds the fuel pump relay) was corroded underneath. I had to flip it upside down(all 4 of them at once) and use electrical contact cleaner and a toothbrush to scrub it clean.

Now the fuel pump runs and the injectors work!

MapleDitch said:

My 1990 quit in the same manner. I had to jump the fuel pump to drive it. Then the injectors lost signal and it would not start.

Ended up being the relay harness(that holds the fuel pump relay) was corroded underneath. I had to flip it upside down(all 4 of them at once) and use electrical contact cleaner and a toothbrush to scrub it clean.

Now the fuel pump runs and the injectors work!

Click to expand...

great thanks this seems to be the fix that makes the most sense to me.

Possible it's something at the fuel pump relay or associated wiring. But when you jumped the relay you should have also been providing injector 12 volt in. Either the power to the relay is too low due to faulty wiring or connectors or the ECU isn't letting the injectors fire, which is almost always the CPS (especially when the fuel pump isn't running).
If you have a new CPS in there the problem may be in the CPS wiring, only one way to know for sure, is to ohm test the circuit.