We still think it is flooding while it is trying to crank. I really need to know how much vacuum it should have. I am wondering if it isn't getting enough air.

 

Trolol
You tried holding the throttle open when cranking?


Just a thought.

 

Yes it doesn't seem to help.

 

Should it pull a vacuum while cranking?

 

Yes, but, probably not a lot. Don't have exact specs.

What does the PCM think engine temp is when cranking cold?

 

Yesterday took the IAC valve out and we thought it might have been stuck so we cleaned it and thought it was fixed until last night when we tried to crank it again. I am replacing coolant temp sensor today because I broke it last night, but before I broke it it did ohm out to spec. I am running out of sensors or things that could be wrong with truck. Does anybody have any other ideas.

 

Still curious on how much vacuum it should pull on start up and the best way to test for it.

 

Should have around 20" vacuum at idle. (engine actually running) Don't think I have ever seen specs for vacuum while cranking.

If it is flooding while cranking, that is going to be related to temp sensor, TPS, or IAT.

 

Ok i just did the test procedure on the tps and it tested great. All measurements within spec. I installed a brand new coolant temp sensor and IAT reads in spec. What is another idea or did i miss something?

 

Now i am wondering if when i replaced the ECM maybe the engine was still flooded which was the reason I didn't think it was the problem. I am now thinking i should have gotten it started to see if it would fix the flooding. Everytime i go through the self diagnosing procedure on alldata diy it always points to a bad ECM.