wellyman

Hello all:

I have a 93 4runner, with the 3.4L conversion. It's been about a year or so since I completed the project. I get this horrible stumble on occasion. It starts when I'm sitting at a stoplight, or pulling out of a gas station, or other times when I'm idling or starting to accelerate. When I'm stopped, it will start to lobe, rpm's fall to under 500, and I have to give it a little gas to keep it from dying. It remains very rough. Once I can start moving, I have learned to push the clutch in, rev the motor, and feather the clutch out. When I rev it, the motor is very rough, and after a few seconds, it will get smooth again. It's like clearing your throat. Highway cruising is fine, never any problems. It's always at either stop, or start and go (city) driving. Sometimes I don't feather the clutch at all. Light turns green, I start driving and the truck is bucking bad, and then it will smooth out, and all of my power is restored and the tires usually bark when this happens and I'm thrown back into my seat. Sometimes this happens frequently, and sometimes I have days when it doesn't occur. Rain and temperature don't seem to affect the matter. Only other thing I notice is strong exhaust odor, which I don't know if this is normal or not. When I pull the truck into the garage, it runs for a few seconds until the door closes and I smell it strongly, unlike my other cars. No codes from the computer. I put on another trottle body and it didn't affect it. I'm about to send in the injectors for ultrasonic cleaning as I'm out of ideas, but I'd like to get everyone's opinion here as to what it could be before I keep wasting money on fixing unbroken parts. Only thing I can think of is injectors, maybe coil? It's quite annoying when it happens, although I've driven it enough that I feel safe it won't break down on me. The motor has about 40K miles on it. It did sit for a short while exposed to the elements at the junkyard before I bought it. Any ideas or suggestions would help alot. Thanks all.

Jeff