need help quick. car is back firing and won't start sometimes

[crash27578]

the past couple of months every now and then the car would backfire and run like crap fora few seconds then clear up and not do it again for weeks at time. Like a idiot i ignored it because of time. Now I'm going on vacation tommorrow and the car wouldn't start. I tryed it again after work and it started but backfires alot now. It dosen't seem to be missing as bad as it did when it backfired before but it still running like shit. I changed the top o2 sensor when it started messing up so I know thats not it. Any sugetions are greatly appreciated.

 

[crash27578]

I forgot to mention that it backfires in between shifts and decel. When it misses it blows a lot of black smoke.

 

[crash27578]

O.K. A few discoverys since the last post. What I thought would be one problem was a few problems. One: the gasket between the manifold and turbo is bad(easy fix) Two: my egr blockoff plate went bad(already fixed it) Threethe one I need help with)the coil that runs 2&3 cylinders isn't firing. I replaced the coil only to find out it wasn't the problem. O.K. here's whats going on now. If the car has been sitting for a while it will start and run fine. Get it warm and turn it off for a few minutes and the coil won't fire, just the 2&3 three side. The other coil that runs 1&4 works fine. I ran a test light on the coils. The red wire stays hot when key is on. When trying to start the car coil 1&4's blue wire pulses like it's supose to but 2&3's stays hot. I really don't know what this could be but I'm hopeing somebody on here knows. I hate taking anything to a shop when I can fix it myself but if I don't figure it out soon I'm gonna have to. :thumbdown

 

[luv2rallye]

Sent you a PM on coil problem.

 

[crash27578]

O.K. I tracked it down to the TPM so I replaced it. Still does the same thing. Start the car after it has sit for a while and it runs, let it get warm and turn it off for about 5 minutes and it won't fire off the #2&3 cylinder coil. I did discover that I can reset the computer and it will start up and run fine and do the same thing all over again. I really think that it is the ECU but I want to make sure. I know to visually check it for cracks, burnt spots, and have a fishy smell. Is there anyway to use a multimeter or something like that to check it further? If it is the ECU what would you do about replacing it? Would you rebuild it or go to something like a AEM EMS or do I still have to have the factory ECU for that? I've not messed with any computer performance setups and I'm looking for a good setup even if it cost a little. Any help would be great.

 

[crash27578]

Starting a new post. "Down to the ECU."

 

[realhp=turbo]

My car did exactly the same thing. Exactly. Anyway I dont know what fixed it, but it ended up clearing itself up when I moved from Spokane to Seattle. Like 2000 foot elevation differnce. I dont know if that had anything to do with it but I did find that it would sometimes clear up while I was driving too. If I floored it and was abusive with it ie; holding it out as long as I could, ect. It seemed to clear its throat. When you figure it out let me know so I can investigate the same area.
mike

 

[crash27578]

The #2&3 cylinder miss was the cam position sensor. Back up running strong. For now anyway!!