John415

Okay guys, I am back again with more of my friend's 86 GXL troubles. I know you guys can help you always do. Heres the story we just put this motor in about 600 miles ago. I know it has a vaccum leak but it runs fine. It started with a new problem. Gregg was just riding along and lost all power, and it revved very slow, and would die in gear unless you put it in neutral. To describe the sound I can simply say, 4 wheeler, no joke. It did this for a while then snaped out of it and ran normal. Then it did it again, 10 miles or so down the road. I drove it today and from his house up to the stop sign not 1000 yds away it ran fine then lost power and sounded like a 4 wheeler. We messed with it mainly revving to about 5 or 6 k and it would snap out of it. By the time we got to the garage it was running like a little kitten, smooth and calm. Then we changed the fan so it wouldn't vibrate a 6k, and too it out for a test drive. It got about a mile then screwed up again, and hasn't come back out of it since. Here are the things we had done/checked: Fuel, changed filter, nothing, Ignition, changed coils, checked plugs for spark great spark no change, Exhaust, hits 7 or 8k with a pretty little fire out of both tailpipes, not clogged, no cats, Compression, Did Whoosh test, Excellent Compression. I am out of ideas and Gregg is out a car. I need your great wisdom forum members! Please I beg of you what can fix this car? I am open to any suggestion.

Thanks for listening,

John

i.didnt.do.it

You check the AFM?

Rob x-7

that also sounds like a TPS issue

John415

I forgot to meantion that last night, We adjusted the TPS with no success as well, even changed it. If the AFM was messed up I thought it wouldn't run?

FrestyleFC3S

we have to talk to you about your tps report

i.didnt.do.it

It'll run with a messed up AFM, just really rich (thats what mine did). Mine would run good off and on until I put on another AFM...worked fine after that.

John415

I'll replace the AFM with another from our parts car, and see if that works. I've heard it might be the cold solder on the ECU, ideas?

Houstonderk

Mine did something like that, until I changed the exhaust gasket.

jack

Did you check all the ground wires? Mine did about that same thing. The Ground wires for the ECU are under the coil packs near the firewall, locate those and give them a good cleaning. There is also a major ground wire under the intake manifold for the injectors, may be somthing to check. Have you opened up the ECU to see if any circuits are damaged? Next time it acts up, pay attention to how far you have you foot down on the gas pedal. The TPS could still be an issue as wel as the AFM. Does it seem to be temperature related?

John415

Okay, after 8 hours of work on this car we have an answer to the 4 wheeler delima. Turned out when it was running bad it acted like it was running on one rotor, we thought spark. I had checked the front plugs before but not the rear. They all fire outside the motor, in the motor it still ran bad. I disconnected the rear plug wires and started the car. I did the same thing no change. Rear plugs only, no start, plus no fuel on the plugs. Bingo!! Primary Fuel Injector!!! We take the intake off thinking we were going to have to change injectors when we discovered that the plug was only half way on the rear injector. Plugged it in hooked everything back up, BOOM!!! Ran great ran strong!! Now it ran good, on both rotors but wouldn't idle and barely run below 2k. I think there is a bad vaccum leak that I can't find and am tried on dealing with. We are gutting the emmisons, any suggestions on how to do this the right way and will this slove the idle problem??

Thanks,

John