1995 gmc jimmy that cuts out?

[pelcos]

bought a jimmy did tune up fuel pump coil ing.modull crank sensor and yet it still runs sometimes for a few hours and sometimes 20 min. and cuts out and when hooked up to a computre it says volatage to high what is causeing this anyone know also i have noitced that someone has cganged the computre what happens if they did not change the chip is there any way to tell if they did and if they did not is there anyway to fix tha please help iam stuck and confuesd on this one

 

[Molson02536]

bought a jimmy did tune up fuel pump coil ing.modull crank sensor and yet it still runs sometimes for a few hours and sometimes 20 min. and cuts out and when hooked up to a computre it says volatage to high what is causeing this anyone know also i have noitced that someone has cganged the computre what happens if they did not change the chip is there any way to tell if they did and if they did not is there anyway to fix tha please help iam stuck and confuesd on this one

Any codes and what are they, here is link for you to retrieve your DTC codes since your have a OBDI system you can do it your self. Post back what codes you have and if you don't have any then it's going to be the long road to finding out what issues is causing your engine not to start.

http://www.troublecodes.net/GM/

There are 2 issues I would look at that these are known for. The CPI injector unit(poppets clog) and the fuel pump. There are bulletins for the poppets clogging and the fuel pump for 2 issues. One for excessive draw and the other for a bleed down from a pulsator on the assembly. I would be leaning towards a low fuel pressure issue when the stall occurs. 55-64 psi is what you should see. For an issue like this you will need to drive this with a gauge where you can see or run the vehicle.

check out this bulletin

File In Section: 6E - Engine Fuel & Emission
Bulletin No.: 67-65-37
Date: June, 1997
Subject:
Intermittent Hesitations, Low Power, and Rough Running Engine in Cold Temperatures (Replace PCM)

Models:
1993-95 Chevrolet and GMC, M/L, S/T Models
1993-94 Oldsmobile Bravada
with 4.3L Engine (VIN W - RPO L35) and HYDRA-MATIC M30 Automatic Transmission only

Condition
Some owners may comment about intermittent hesitations at ambient temperatures below -10°C (14°F). The hesitations may also be associated with low power or a rough running engine. This condition may lead to a closed throttle stall when stopped. This condition, if encountered, would most likely occur within the first few minutes of engine operation after a cold overnight soak. If the low power condition were encountered, the engine would run normally after one vehicle ignition cycle (Off/Start/Run).
Cause
Under certain conditions a high frequency transient voltage spike back feeds into the engine controller (PCM) and causes it to reset. PCM resets would manifest themselves as a bump or hesitation. Infrequently these resets lead to an incorrect fuel/spark run mode which is associated with the low power condition.
Correction
Replace the PCM with a new PCM. Choose the appropriate PCM from the list below.
Year Model PCM Part 1993 M/L and S/T 16245357 1994-95 M/L and S/T 16245358

Good luck and keep us all posted