My 89 5.7 stalls about 10 minutes after starting and will not restart for an hour or so.

I've replaced the ICM, plugs, cap, rotor, wires, and coil. I have spark and fuel, but for some reason it won't restart once it stalls for an hour.

Don't know where else to look ??

 

for fuel did you check pressure? should have 62-90 kPa (9-13 psi) engine off key on

 

If it doesn't start, then you probably don't have spark & fuel! Good spark & 9-13psi fuel pressure. If it will fire up with gas poured directly in the TBI then it's probably low fuel pressure (time for filter/pump)

Make sure ICM has good ground (dizzy bolt tight). Your timing might be set wrong. Rotate engine to TDC with breaker bar on crankshaft pulley bolt and see where the distributor is pointed. Verify it's TDC and not exhaust stroke by pulling spark plug #1 and feeling for puff of air as the timing notch on the harmonic balancer starts to approach the timing tab.

From there you can try advancing it a bit to get it started, and then reset it with a timing light (turn dizzy counter-clockwise to advance). It'll idle anywhere from 10* retarded to about 40* advanced when the EST wire is unplugged, smoothest idle will be around 20*-25* advanced (ICM controls this based on the ECU PROM when the EST bypass wire is connected)

You can also hook an LED+resistor to the tach wire off the coil and see if you're getting proper spark pulses from ICM when you crank.

 

I have spark and fuel, (pressure 11psi) if anything by the smell I have to much fuel. Could my TBI be dumping to much fuel and flooding the plugs?

 

I just replaced the coolant Temp Sensor and SHAZAM My problem is fixed !

Figured for $12 it was worth the test since I thought for some reason it was flooding.


Thanks..

 

ya those coolant temp sensors can cause some crazy thing.