intermittent power loss/stalling

[turbohounds]

I'm at wits end - hopefully someone can offer some suggestions what to try next. Pretty much ever since I purchased my '92 it has had a random stalling problem, which comes in episodes about every six months. It will die, and restart again within about 30 seconds and be fine. All of the normal maintenance items have been replaced several times (plugs, wires, timing belt, no boost leaks, etc). My first thought was ECU capacitors, no help. Second, bad ignition coil, no help. Third, maybe my wiring had a bad ground, rechecked everything and it's all good and properly soldered.

For the last two days crusing at a steady 60mph, I lost all power. Apparently, at speed the engine could stay running, the RPMs looked fine, speedo worked, but I couldn't maintain speed. At no throttle, it slowed faster than without, so I think it was running some, maybe on a cylinder or two. I could still hear the fuel pump, and there was no click in the ECU or flashing of the SAFC. After 10-15 seconds, and slowing to about 45, it popped a few times and began to run fine again. I'm thinking it's getting fuel (hence the backfiring and loading up while it's not firing) but not firing on all cylinders properly. When stopped there isn't enough momentum and it stall. I'm thinking there must be an intermittent problem in the ignition system. Possibly the power transistor? What am I missing?

Car is a '92 AWD Talon, with 550s, big 16g, 2G MAF, SAFC, and lots of other little things. Problem was around before and after any and all mods.

 

[larryriverside]

my friend is having the same problems except wourse. he gets massive knock a lot too. 43 counts. pops through the intake. turbo gets red hot like no other i have ever seen before. i told him that he should park it till we figure it out. sometimes it will come out of it for a little bit, but it still comes back. i just don't know.

 

[laserblue]

I cannot be sure, of course, but many problems with 2 cylinders having no spark... or losing all spark - comes from an intermittent power transistor unit. It is the gizmo that takes the pulses from the ECU and sends them to the coil packs. There is a test procedure in the s/m but if the car is working at the time of the test, the transistor unit will test good!
Another thing I've read [but don't know anything about] is that for some reason, the injectors stop pissing fuel.

Sorry for the hap-hazard answer... Maybe another reader can help now!! . . . I'll shut up and go away!!!!!!!

 

[larryriverside]

well, after staying up till 6 in the morning helping my friend. we fixed it. still not sure what it was that we fixed. we took the timing belt off made sure everything was timed right, and on their marks. put it back together, then timed it with a timing light. took it for a drive, and everything is good. "there is a God"

 

[turbohounds]

I'd bet your problem was the timing belt off a tooth. Mine had jumped one tooth when the balance shaft belt broke. Ran great off boost, but would knock like crazy under any boost. Glad to hear you figured out your problem. I think I'll try a new power transistor and pray that fixes it.

Originally posted by larryriverside
well, after staying up till 6 in the morning helping my friend. we fixed it. still not sure what it was that we fixed. we took the timing belt off made sure everything was timed right, and on their marks. put it back together, then timed it with a timing light. took it for a drive, and everything is good. "there is a God"

 

[larryriverside]

ya i am glad that is over. good luck w/your problem. it's nice to hear it run like it should. this car hasn't run right for my friend from day 1. so, i am sure he is happy. i haven't talked to him since. he must just be driving around all over enjoying it. ahhhh, that feels good