Ok, a few weeks ago I bought a 1978 Pontiac Bonneville with 301 4.9L engine off craigslist; the previous owner sold it because he thought it had an engine problem thought it spun a bearing and garaged it for the last 2 years. I work for a car dealership so I had it towed to work, I changed all the fluids and filters (engine oil, coolant, brake fluid, transmission fluid etc.) I also replaced the gas tank and fuel pump, and replaced the valve cover gaskets. After I put a new battery in and a few pumps of the gas pedal the engine fired up but shook and ran rough, we tested the plugs and it 2 were not firing, also didn't help that they were autolite spark plugs. So I went to AutoZone and I bought new AC-Delco plugs, wire set, distributor cap, and rotor; replaced everything and the engine ran great.
Now the problem, the car would not go into reverse and the transmission torque converter started grinding so it needed a new transmission. We pushed out into the parking lot and until I bought a used transmission. Fast forward one week, brought the car back into the shop to install the new transmission; started right up shifted into drive and drove it into the shop as soon as it got to the lift the engine stalled out. We tried starting it again and again but it wouldn't turn over it started to smoke near the distributor; so we pushed it on to the lift installed the transmission and moved on to trying to figure out the engine problem.
We checked the firing order, plugs, distributor everything worked properly. We checked the carburetor to make sure it wasn't clogged at the fuel filter, it gets plenty of fresh fuel. I had a similar problem years back with my 1984 Oldsmobile Toronado and changed the ignition control module and it fixed the problem. So we changed the ICM still nothing. The only thing I haven't replaced yet is the actual ignition coil, but I don't want to keep throwing parts at it. It appears that the car either isn't getting enough spark or not enough fuel at the same time, this car doesn't have what would be considered common problem parts (crank sensor, oxygen sensor, throttle position sensor) so I'm kind of at a loss for words. I can't see it being a carburetor problem because it ran great the week before and there is fuel going to the carburetor, I also can't see a problem with the starter because it starts like it supposed to the engine just won't turn over and run again. Any thoughts on what the problem could be would be greatly appreciated.
Now the problem, the car would not go into reverse and the transmission torque converter started grinding so it needed a new transmission. We pushed out into the parking lot and until I bought a used transmission. Fast forward one week, brought the car back into the shop to install the new transmission; started right up shifted into drive and drove it into the shop as soon as it got to the lift the engine stalled out. We tried starting it again and again but it wouldn't turn over it started to smoke near the distributor; so we pushed it on to the lift installed the transmission and moved on to trying to figure out the engine problem.
We checked the firing order, plugs, distributor everything worked properly. We checked the carburetor to make sure it wasn't clogged at the fuel filter, it gets plenty of fresh fuel. I had a similar problem years back with my 1984 Oldsmobile Toronado and changed the ignition control module and it fixed the problem. So we changed the ICM still nothing. The only thing I haven't replaced yet is the actual ignition coil, but I don't want to keep throwing parts at it. It appears that the car either isn't getting enough spark or not enough fuel at the same time, this car doesn't have what would be considered common problem parts (crank sensor, oxygen sensor, throttle position sensor) so I'm kind of at a loss for words. I can't see it being a carburetor problem because it ran great the week before and there is fuel going to the carburetor, I also can't see a problem with the starter because it starts like it supposed to the engine just won't turn over and run again. Any thoughts on what the problem could be would be greatly appreciated.
