North Coast Cab

Can does not like to be real hot and won't restart when full up to temp without pumping the throttle liek crazy. It will then stumble and fire, running rough for a few seconds before it levels out and runs great. ICV was recently replaced too. Anyway, I am thinking Head Temp Sensor. Any other ideas or comments before I start throwing money at it?

TIA, John

Stealth 993

Head temp sensor sounds right. You might also have leaking injectors.

Have you held the throttle down when you start it?

North Coast Cab

Yes but it seems to only start if I put then gas quickly.
Can I disconnect the head temp sensor and try it? Fires up in the morning just fine.

North Coast Cab

Update. No start cold.
Fuel pump does not run with DME relay. When jumpered it runs but will not start. There is fuel in the rail though.
No spark.

DME? Where to go from here?

Steve Weiner-Rennsport Systems

Got a spare DME relay????? Thats the place to begin. Remember, this relay powers both the DME & fuel pump.

If that doesn't work, its time to check crankshaft reference and position sensors.

North Coast Cab

There is no spark and no fuel intermittently at start-up. The Fuel pump is not running with the ignition on. If I jumper the relay the FP runs but there is still no spark. So it seems to me either the DME is bad or the mentioned reference sensors are working intermittently, more likely.
My only concern is it is just at start-up, once running it is rough for 5 seconds and the runs great for the duration.