I have a four cylinder 1991 mustang lx, I was driving on the freeway and
boom I lost power, couldnt get above 50 miles and started smelling real
bad. I had the pedal to the floor and just bogging down terrible, shaking
and then I pulled over. Looked under the car and the first catalytic
converter and exhaust pipes into the engine were red hot. Took it to the
mechanic and it did it again, we tested the coil packs and found a cylinder
was gone, we got some used but working coil packs and put them on, replaced
the fuel filter, and it seemed to work for awhile, then it did the same
thing to my wife about a month and a half later. Replaced the plug wires
and plugs, car responds great but after it heats up it drops a cylinder
again. Once it cools off I can drive it like normal. No error codes show
up on the computer. Kinda stuck as to what to do next.
At this point, before doing anything else, you need to check the cat for blockage. If it was "red hot" it has probably collapsed inside and will need replacement before you can go any farther with the diagnosis.
There are two cats on this car and the first one that was hot has been drilled and cleaned, leaving one cat intact.
Oh, another one of those that leaks out information as he see's fit. Good luck getting help.
Just today we had a bit more info to add, I started the car when it was right cold and the cylinder was not firing, so that eliminates the the heat issue, my dad and I also figued out it was cylinder # 1 'cuz we tried to start it with #2 plug wires off and it didnt go, then we took off #1's and it went just the same as when they were on, idling really hard. So I am not sure if I should go and look for a new DIS (distributerless ignition system) or does it have to do with the computer?
I think you should just get rid of it. No one should own a 4 cylinder mustang.
Well the car is fixed, I got the DIS replaced and that solved my problems, no more misfires. Thanks for all your help.... :orglaugh:
You found the problem with some troubleshooting.
I would still make sure the cat that is remaining does not become blocked. Running a car as long as you did with a dead cylinder pushes a lot of raw fuel into the exhaust system.
I would also be careful about drilling out cats. Technically, drilling out the cats is tampering with and disableing the emmission control equipment on a car which is a violation of Federal Law.