TO start off I have had random rough starts over the last 6 months. After the truck was warm and I would stop for a short time, less than 30 min , the truck would start but idle low about 400 rpm and be really rough. It didn't always happen. I never looked into it because if I gave it a little gas and then drove off it went away. There were no engine code at this time.
Fast forward to the last 2 weeks and I have had a similar issue.

First I got engine codes 4 and 7.
I replaced and adjusted the tps and the code 7 went away. I found a frayed wire on the coolant sensor right on top of the thermostat housing. I need to clear the codes again to see if the code 4 goes away.

I am still having a starting problem thought. It fires right up and idles @ about 900-1000rmp for about 1 sec then goes to about 400 rpm and gets slower till it dies. It will do the 5-6 time before it idles normally and warms up @ about 900 rpm. It only does it when the engine is cold. What should I check now?

 

I would change your circuit open relay. Sounds like your fuel pump is shutting off. Also check the operation of the flapper in the AFM and make sure it moves easily.

 

good luck

 

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