Hello there, I have searched the forum and am not sure what our next step should be. I was hoping you all will help in guidance please?
I had my 96 454 Vortec completely rebuilt by a very good local rebuilder. I had them rebuild my 99 350 Vortec a handful of months ago and it is running very good. Back to the 454.
I picked it up from the rebuilder and had my plan "B" mechanic working on it. Mechanic "A" didn't want to do the swap. So, Mechanic "B" installed the 454 into my dually and had an issue getting the distributor timed properly. He doesn't have a computer or scanner able to tune it so he installed it as good as he could and it was running really really rough. He said the catalytic converters were bad and needed replaced and it needed tuned better with a scanner or computer.
At this point I paid him for the install and drove it (BARELY) to mechanic "A" so he can use his Snap On scanner to tune it and remove my catalytic converters and replace them with exhaust pipe.
He diagnosed it as having a consistent misfire on cylinders 2 and 3 and he can not figure out why. I will list everything that has been done.
- New distributor with cam sensor, rotor button and cap
- Even though he removed the O2 sensors, he unhooked the exhaust from the manifolds to make sure the bad converters wasn't causing the misfire
- Fuel pressure (good), spark (good), compression (175), injectors (good), plugs (new), wires (good), timing (good)
- Checked for pinched wires, bad grounds
I have a friend who knows a lot about various mechanic work and he said his next step would be to "flash the ecm", I don't think mechanic "A" has done that yet.
After knowing all of this, does anybody have a suggestion on what we should do next? I would sincerely appreciate any help at all, this has been very frustrating and I just want to get my 454 running good again. I will even compensate the person who is able to direct me to the issue and help the mechanic with the knowledge to get it running properly.
Thank you in advance.
I had my 96 454 Vortec completely rebuilt by a very good local rebuilder. I had them rebuild my 99 350 Vortec a handful of months ago and it is running very good. Back to the 454.
I picked it up from the rebuilder and had my plan "B" mechanic working on it. Mechanic "A" didn't want to do the swap. So, Mechanic "B" installed the 454 into my dually and had an issue getting the distributor timed properly. He doesn't have a computer or scanner able to tune it so he installed it as good as he could and it was running really really rough. He said the catalytic converters were bad and needed replaced and it needed tuned better with a scanner or computer.
At this point I paid him for the install and drove it (BARELY) to mechanic "A" so he can use his Snap On scanner to tune it and remove my catalytic converters and replace them with exhaust pipe.
He diagnosed it as having a consistent misfire on cylinders 2 and 3 and he can not figure out why. I will list everything that has been done.
- New distributor with cam sensor, rotor button and cap
- Even though he removed the O2 sensors, he unhooked the exhaust from the manifolds to make sure the bad converters wasn't causing the misfire
- Fuel pressure (good), spark (good), compression (175), injectors (good), plugs (new), wires (good), timing (good)
- Checked for pinched wires, bad grounds
I have a friend who knows a lot about various mechanic work and he said his next step would be to "flash the ecm", I don't think mechanic "A" has done that yet.
After knowing all of this, does anybody have a suggestion on what we should do next? I would sincerely appreciate any help at all, this has been very frustrating and I just want to get my 454 running good again. I will even compensate the person who is able to direct me to the issue and help the mechanic with the knowledge to get it running properly.
Thank you in advance.