I am trying to help my neighbor fix his 89 which seems to have developed multiple issues at once and I dont know where to look for a common thread.
It was running fine, he parked it, a week later it was a no start. I checked it out for him and immediately discovered it had no fuel pressure and the pump was not running. Plenty of juice at the tank, so I gave him a spare I had sitting around and he replaced it. Now the pump ran and we had fuel pressure but still no start.
So I checked for spark and injector pulse and can find nothing. No 12V at the distributor either. There is definitely no spark, I dont have a noid light so I used a digital voltmeter to check for injector pulse, not 100% sure that can be done that way.
When I plug in datamaster it seems to communicate fine with the computer. All this going wrong at once just doesnt make any sense to me. Ideas?
Thanks
Roy

 

Try cranking the car for 20 seconds straight....watch the RPM gauge for movement. If you can see the RPMs show up then that means the ICM and pickup coil are most likely OK. Or you can remove the ICM and have it tested at the auto store for free....but you'll still need to test the pickup coil with an ohm meter.

You can strap a timming gun pick wire on one of the plugs while you crank the engine for the 20 seconds to see if a spark ever occurs...it takes about ~1 full revolution of the distributor before the unit will fire the plug.

There are fuses for the injector harness in the fuse panel marked inj 1 & inj 2....you may want to check those out too.

If everything (fuel pump, pressure, ICM, pickup coil, ing. coil, fuses and you have injector pulses) check out to be OK and the car still will not start -- spray (~10 seconds) some ether into the throttle body and give her a crank to see if she will fire up for a few seconds.

Bad OEM "Multec" brand fuel injectors are a common problem for the '89 cars. Even if these injectors ohm ok they can still be bad.

If you need more info use the forum's search function....tons of info out there. Other than that I'd also recommed your buddy get a FSM (factory service manual) for his year car they run about $130 for a new reprint....I saw used one in the C4 parts for sale section the yesterday for much less.