I don't think this problem is related to all the other issues. Anyway,, what happens is after a trip to the store The engine runs fine with no problems at all.
It has all the power that a 6 cylinder should have and good pickup.
When leaving (sometimes, not all the time), it acts like its not getting enough of something, air/fuel mix or timing, Injectors? Then the engine smooths out and runs like it should.
So far I have replaced the TPS sensor, Map Sensor, Distributor and rotor button. I removed and cleaned the throttle body.I have also ran a good top end cleaner through it. Any suggestions on what to check?
Dave

 

How long does it act like this?

Leaking injectors?

 

Only a short time. Maybe 30 seconds or less. The injectors is what is sounds like to me, maybe I should run some more cleaner through it? I think the truck was road hard and put away wet before i got it.

 

Adding something to the fuel usually doesn't work if the injectors are leaking down. They usually need to be flushed directly or replaced.

 

Borrow a fuel pressure tester from a local parts store that does the loan-A-tool thing. Plug it into the test port on the fuel rail of your truck and check the pressure. From what you are describing your main focus should be to check if the fuel pressure leaking down when the truck is shut off. The loss of fuel prime will cause hot start issues because fuel vaporizes and blocks the liquid fuel until it gets pushed out the injectors. I have a 3.9 Dakota that drops to 0 PSI at the rail in less than 30 seconds after shut down but runs fine once it is started. The fuel pressure when running should be between 45 and 54 psi and not drop below 30 psi for at least 5 minutes after the truck is shut off. If your truck fails this test the next step is to figure out if you are leaking past the injectors, externally or back through the fuel check valve and pump.

 

I never thought about checking fuel pressure.
I went about 40 miles out yesterday , with about a 30 to 45 min layover and then back. Not a hiccup. The engine was running just a little rough at stop lights on the way back, but if you were not paying close attention you wouldn't have noticed it. I can't check it today It's raining, and i gotta do all my werk outside.

 

Todays Pressure Check.
Engine Cold, Key On : 42 PSI
Engine Running : Bounces 40-50 PSI It was a really good jiggle.
With Engine Off for 30 Min : Start 28 PSI Climbed to 45 PSI Weird....did it twice.
Second time 26 Psi to 42 Psi.

 

The pressure climb after shut down is likely the fuel expanding in the fuel rail due to the heat coming off the engine. you are sitting just a tad below spec for pressure with the engine off but 2 psi could be the gauge or the angle it is viewed at. Bouncing between 40-50 rapidly could indicate an issue. The fuel rail pressure should be fairly stable with the engine running. If the fuel pressure needle is snapping in a rhythm it would indicate an issue with one particular injector. Isolate the gauge from engine vibration if possible for the most accurate results.

 

I was holding the gauge when the engine was running. How do I check the injectors?

 

YouTube has some great advice on this. I actually built the small tester and went through each and every fuel injector and found out it wasn't causing my problem. I didn't get any codes at all and the truck would act up after it was warm and then straighten out. Look at your upstream O2. After changing this chasing another problem I guess I got a bad one. Put the old one back and problem went away. ? Lazy or not changing the fuel trim fast enough maybe? I forget what brand it was.