1990 sb truck/ 22re won't start. no codes. no spark, coil wire to head. rotor turns. measured .020 dist. air-gap. 12vdc at coil's primary. pick-up coil, coil wire, coil, igniter module are good. will check rotor position and for loose grounds today. can't find the cpu's fuse. any suggestions for another location. its not in the driver's side kick-box as per manual. can a slipped timing chain cause the cpu not to allow fireing. have i missed anything. thanks eh, me

 

Any history ?
was it fine and then one day it flat wouldn't start or ..........





Fred

 

Truck died while running. Ran very good previously. Engine has about 150k miles. fluids routinely changed. engine, trany, cab, gas tank and wiring harness recently changed to 1989 chasis. I used the 89's instrument cluster in the new cab, for esthetics. perhaps this is why there are no codes or bad bulb. Grounds appear to be in good condition. What I can't understand is why it won't fire. Question? if the timing chain has slipped a tooth would the CPU prevent fireing? Again thanks, Me

 

Check and make sure your Air Flow Meter connection hasn't come off.

 

You mean they're OK per ohm specs in the FSM?

IT could be a bad connection.. But ignition is hard to debug without an oscillioscope.

The signal path is:
distributor -> ignitor -> ECU -> ignitor -> Coil

You really need to check you IGt signal, but the FSM says to do that at idle.. not much help if it won't run.

Know anyone into electronics?