Hey, I have a 1994 Nissan Sentra XE. I got the car in September of this year. The car had a very rough idle and when I'd drive it and turn the steering wheel the car shut off. Also when you turned on the heat or ac it would get more rough. I believe the problem was a cracked pcv hose that connected from the intake manifold to the pcv valve that screwed into the valve cover. I found out the problem after having to remove the valve cover due to oil getting in the spark plug wells. This I knew had to be the seals gone bad so I got new seals and when removing the valve cover I discovered the hose. But the problem mainly is that after I changed the alternator the car had started and slowly died off. I looked at the alternator and realized that the belt wasn't on right and when I fixed the belt and attempted to start the car it cranked but didn't start. This led to me discovering the oil in the spark plug wells, and so on. I tested the spark plug wires by sticking a screwdriver in it and holding it about a 1/4" away from a the exhaust manifold heat shield and had somebody crank the car. It sparked as it should. There was no zap or anything, but it was a fine bluish white spark. So I thought the spark plugs were probably bad. I tried spraying starting fluid into throttle body to see if it was a fuel problem already and it still didn't start. I tried adjusting the alternator belt. So thought it had to be the spark plugs. But when I replaced the spark plugs it still wasn't starting. I then tried to see if the maybe the wires weren't set to the right firing order at the distributor. It's 1 3 4 2. So I tried it at with the wires placed in that order starting from the post that said 1 on the distributor cap. Then I tried it at the post that was marked #1 cylinder post in the haynes service manual. I tried it in reverse thinking maybe I was wrong about the rotor direction. I checked to see if the rotor was turning which it was. But it still didn't start. When I put place the #1 wire at the post marked 1 on distributor cap in both orders it will crank very rough especially if I try to press the accelerator pedal while starting it. At the post from the service manual it cranks smoothly but a popping noise comes from the fuel tank area. I slowly removed the gas tank cover and it made a whooshing sound like it was releasing lots of built up pressure. But it still doesn't start. The car has been sitting in my yard since the time I got it. The only time it has moved is when I attempted to drive it and it cut off as soon as I turned the steering wheel. What could be causing my car not to start. Any help would be greatly appreciated.

. Check all under hood and under dash fuses with a test light or multimeter.

. Check for codes.

. Replace the Ignition Control Module (ICM), if the problem persists.

Could that be causing it not to start or something else because there's no blown fuses or anything. I still have to check the relays and I plan on taking out the spark plugs and hooking it to the wires and see if it will spark when I hold it against a ground

A bad ICM is likely the reason it doesn't start.

Is there a way you can test the icm to see if it's bad or not?

ICM tests are unreliable. Take it to AutoZone and they should be able to test it on a Well's machine. My experience is it's bad if it tests bad; however, if it tests fine it may still be bad.

I followed the resistance tests for the icm in the service manual for the vehicle and noticed it seemed terminal a was messed up. They also referred to it as a power transistor. I think that has to be the problem since I took out the plugs and tested them and they are sparking. So I should probobly change it rite? Thanks for the help. Have a happy new year.

I would.

I changed the icm and the car is still not starting. It's doing the same thing as before. I also noticed the cel goes off when I turn the key to the start position. Is that normal? And what else could be causing it not to start?

Don't know if I missed that you had good Fuel/Pressure as well?
Still need the Basic 3, Compression seems good?
Fuel and Spark at the right time is all that is left.
Maybe a Compression test, if all else(can reveal certain problems)
Fuel Filter?