Stalls When Warm?

[dtoxn]

1991 k1500 350TBI. Starts and run great when cold, take for ride and stalls when warm, only longer trips, 10 miles or more. After it stall let it cool down, and truck will restart and run fine again for the next 10 miles or so. Tells me some kind of temp problem tell in computer to shut down? Took temp readings with heat temp lasor gun Temp is running about 210 deg at block by plugs, and 190 at thermostate housing.

 

Changed out ECM on distributer, temp sensor & sending unit, thermostate (195deg). Upper hose is hot, so know that thermostate is working correctly. no leaks (antifreeze or vaccume).

 

Not sure what to look at next? Idle air mixture sensor? Could that be causing a problem when it get hot on long trips?

[Wolverine350R]

I don't know if this applies to the trucks, but my 91 TPI 350 Trans Am did very much the same thing and it turned out to be the ignition control module in the distributor. Apparently if they get to hot they quit working.

 

Just saw that you replaced th ECM in the dist..probably the same thing. How about the coil? That was also suggested to me when I was having my problems.

 

Good Luck.

[mjlimo82]

Spark controller module? Located on bracket above the valve cover on the right side of the motor...

[rodram]

I agree with one of the above posts... that the ignition module can cause terrible grief

 

ALSO... check the Coolant Temperature Sensor (CTS) on the top front of the engine .. this sensor sends a signal to the ECM to control the fuel mixture... when they fail, the engine continues to get a very rich fuel mixture and will often stumble badly, stall, or refuse to start when warm. (... these trucks have two temperature sensors .. one for the ECM control and one for the dash gauge.. did you check/change the right one)