sorry about the wait had to work a little late got a chance to test the fuel pressure on the truck seems to increase to 58psi when trying to give it steady gas about quarter throttle and then engine stalls out. Restarted the engine tryed to give it about half throttle pressure increased to 60 psi and then engine stalls

 

Yea fuel isn't the issue and missing something here.

How does it run other than the stall at quarter throttle say sitting at idle even up to and just before that point?

What I mean is are you sure it hits on all 6 cylinders, you're sure it doesn't have a miss all the time or just some times stumbles/trembles as if missing on multiple cylinders.

Or it runs rock steady not missing a beat?

Your computer sees "lean" so its constantly trying to swing rich even full rich to make up for it.

Either its getting that fuel or its not but it doesn't know it. Your spark plug reading IE; "white and blistered" (should take a minute to check more than one of them if you have not, find out if its limited to one or two cylinders), tells us that it is lean that it is not getting that fuel. Your opening the throttle allowing more air rush in creating a stall condition also tends back that up.

So question is and one perhaps should have asked earlier, does it hit on all cylinders all of them equally participating?

If not sure with it sitting at idle pull a plug wire off the cap, loosen the wires before starting it as so they just sit on the cap. Use insulated pair of pliers to lift the wires off one at a time.
Aviod leaning on the fenders, you do not want to be grounded out while lifting wire away from cap.
Lifting wire off cap rather than plug is the better option, wire is dead once its couple inches from the cap. Remove at the spark plug end the wire remains live the whole time.

Pay attention to the sound and speed how strong the engine idles, cylinders that are firing you will note a small change in idle speed engine will stumble slightly wire off pick right back up wire back on.

If a cylinder is not participating there will be no change in the way the engine runs when you remove the wire and or put it back on.

Your comment about the slight hesitation under light pedal you've never been able to correct, still doubting its the computer but do not know what steps have been taken in the past in attempt to correct it, how in depth that process might have been.

 

hope this helps

 

Not sure how accessible the injectors are on the I6 but if you could connect a noid light to few watch it see if the injectors are being fired hit and miss style.

If so you see a unstable flash pattern next move would be narrow down what causes its, a simple circuit issue as in problem in the harness, or is it a problem in the PCM itself.

If see it attempt to narrow it down, is it one or both batches or is it limited to only a couple of the injectors. Again, based on your latest comments about how it runs sounds like it'd be more likely to be both batches effected = all cylinders, might only be one of the two though but jumping ahead little bit.


Based on your comments last post it should take much time or effort to determine if that is what is going on or not, not like its not going to screw up for the test!

Make sure the computer grounds are tight/clean/present, the smaller gauge wire off the negative post on the battery, is is there and has a clean connection at the fender and battery for starters.

 

I will have to get noid lights from work but injectors look like they're pain to get to might be able to hook up to the number 1 and number 2 injector. also did check all the grounds including the one for the computer for continuity and voltage drop test

 

there's one thing I forgot to mention after installing a new distributor seem to make all of this worse. before the new distributor i had a start anf stall problem but after you would start started up about 3 times it would stay running on the fourth try and it would be fine until it was cold the next morning

 

Haven't had much time to post for a few days. So here's the update on the situation.
I changed out the new dizzy and put my factory one back in and it remedied half of the problem
Truck starts up better and it tries to stay running longer on its own. I think I may have found the root of the problem. Seems to me that the ECU is having trouble relearning after battery is unhooked. The only reason I say this is that every time I disconnect the battery for a period of time the it makes the problem worse than it was before.

does anyone have any thoughts on the ECU causing this?