92 4.3 cpi help

Couple friends and I have been tryin to get this truck to run properly for a month or so. First it would get a hicup when crusin then finally died. Couldn't get to start then I replaced the FPR due to washing on the passenger side. It started right up and drove great that night. Started the next day and went to drive and it started acting up again eventually dieing and not starting. FInally would start and idle but would die under load, then back to not starting again. While tinkering one day I noticed it had a alarm on it and pulled the fuse and a few hours later it started and drove great. Then bad the next day. It would start but had no power what so ever. I would have to accelerate slowly then it would bog down and catch it self back up.

Yesterday we cut the cat off due to it being clogged, with same result of no power. Changed cap/rotor, plug wires tested ok, plugs looked new with proper gap, fuel pressure is 65 at prime after the filter change and 60 while running. Ran seafoam thru vac line and got some smoke but not a whole lot. When engine revs to 2500-3k it backfires. Checked the timing and it is set to 0 degree base timing.

Any suggestions would be greatly appreciated. Thanks
Sam S

Good hot blue spark?

Set time with base time ESR wire disconnected?

Any check engine lights or codes?

Any engine miss?

What is the engine vacuum reading at idle and at 2K rpm?

I kind of had that same probs your describeing, i replaced the ignition coil and all was well

You might have a loose electrical connector on the injector. The blue and red wires for the injector exit the front of the intake manifold through a 1” grommet. Try giving a tug on the wires with needle nose pliers and see if anything changes.

ok back from working on truck today.

new ignition coil-results were same as with older one.
Vac- 12 at idle. 15 2k rpm
fuel pressure- 60 at prime, 58 idle, 60 when the bog down occurs 92-3k rpm.)

gettin ready to do a new spider tomarrow. Thinkin a poppet it clogged or somethin. Also the part store threw in a crank sensor so i gonna install it to.

Any idea if this could be ignition module related?

could be the ignition module does it act up after you drive it a while or as soon as it starts. Pull the ignition module of and take it to the auto store most can ops check them on the bench.

Engine vacuum is low.
Check base timing and egr valve for stuck open.
Engine miss or low compression or large vacuum leak will drop vacuum to.

Found the vac leak while replacing spider and nut kit. All is good on that end.

Now the new problem is that it seems to lag in the shifting. At first it would wait way to long between 1st and 2nd. Now I noticed it don't seem to want to get out of 3rd. Seems like all power loss and kick the tranny down. I dunno. So many problems. Lets hear some more ideas.

Found the vac leak while replacing spider and nut kit. All is good on that end.

Now the new problem is that it seems to lag in the shifting. At first it would wait way to long between 1st and 2nd. Now I noticed it don't seem to want to get out of 3rd. Seems like all power loss and kick the tranny down. I dunno. So many problems. Lets hear some more ideas.

Proper testing and inspection.
MT

Just so we know I bought this truck screwed up. I would in no way treat my vehicles like this. Obviously the previous owners don't know standard maint.

So what would I be best place to start on the transmission?

Also thank you everyone on the previous input. Really helped tracking that issue down.

Just so we know I bought this truck screwed up. I would in no way treat my vehicles like this. Obviously the previous owners don't know standard maint.

So what would I be best place to start on the transmission?

Also thank you everyone on the previous input. Really helped tracking that issue down.


Engine running problems first.
The engine has to be running right for the transmission to work right.
What is the fuel pressure at?
What is the engine vacuumm reading?
Have you base timed it?
Any engine codes?

No codes. Fuel pressure is 58 idle and 60 2k rpm. Vaccum we didn't check after spider replacement. I think engine is fine now. only has problems when you drive.

Late shift from 1-2. 3rd is a easy shift but truck get sluggish arond 40 mph but engine will sound and run strong. This is a suto aswell. When in 3rd it acts like it tries to shift up around 40 mph then get hung up and loses power and downshifts falls back to 3rd. By chance anyone know the shift points. Believe the trans is a 700r4. Believe that is the trans that came on a sonoma GT

Did you get the TV cable hooked back up good and adjusted?

I wasjust reading about the TV cable right before I posted this. I will have to go double check and make sure the cable got hooked up correctly. Would you need to re adjust or cable after unhooking to take pelinum off or just make sure its reinstalled the same way it came off.