First off i have an 86 gxl with a new street ported motor with less than 1500 miles on it. i have never been able to tweek the idle to the right mixture or idle speed. i have tried playing with the idle adjust screws and idel speed screw..but that is just a side point with my problem. It starts fine and does its usual idle, but when i rev it it goes to about 2800 to 3200 and just pretty much cuts out? the tach needle falls down immediately and i leave off and it goes back to idle, it kind of feels like the engine just turns off. but it doesn't lose electronic power or stall. at first it only happened a little.. once in a while.. now its not driveable. its running really really rich because of the bad idle, so innitially i thought since i didnt replace the old o2 sensor when i put in the new engine it may be that, and that maybe have burnt out my spark plugs because it was overloaded with fuel. so i got new plugs, plug wires, and o2 sensor. when i put the sensor in i noticed the the o2 sensor wire was broken meaning no o2 sensor was being sent to the the engine. Is that what it could be? i tried splicing the wire back with the other one but its almost impossible to do because the gauge is small and i have no wire play. But could that be what that problem is? or could it be something else? i just need ideas? Thanks

The o2 sensor would not cause your problem.. This is very strange...

yes, the o2 sensor doesn't make that much of an impact on the engine, it can't be that.

Maybe your AFM is sticking or something?

So you think its my AFM? I was starting to think tonight it might be one of my coils or my alternator? Are they possiblilties? Ill check my air flow meter to see whats up. So it's defineatly not my 02? Thanks

well the tach is driven from the ignition, so if the tach cuts out i'd start looking at the ignition system



mike

i dont think it's the ignition, it could be but its not just the tach that falls the whole motor pretty much stops for a second.. it's hard to describe. it almost feels like what happens when you are driving in frist gear at like 3500 and feather the gas a couple times and the car starts rocking back and forth.. it feels like the fuel cuts out.. or the air cuts out? Could it have to do with one of the three adjustable screws? anything will helps thanks!

hmmmmmmm



ryan

Could it be your secondary injectors, that sounds like the RPM that they come in at, but I'm not sure.

well maybe it is the fuel cutting off?



mike

why would the fuel cut off on a n/a?