Hi everyone, long time listener, first time caller. I've got some trouble with my 92 pickup 5spd with the 22RE motor. The truck starts and runs perfectly when cold, but not long after it has reached normal operating temp the truck will not idle well (rough to the point of stalling) and it will stumble/hesitate on acceleration/load. If I keep on the throttle it usually will come out of the stumble and then accelerate hard. Without a load, in neutral, the engine will rev freely. Recent work includes new cap/rotor, wires, plugs, filters. It has been running perfectly up until yesterday when the trouble started. I've checked the cap for moisture and found none. (it has been raining ALOT). Please tell me there is an easy (cheap) fix

Thanking you in advance,

Dingo Joe...

 

PS - I've also tested for vaccum leaks by spraying brake cleaner around all the lines and I did not detect any surging in the idle. Truck is stock...

 

bump. is this thing on?...

 

Hmm... Almost sounds like a fuel delivery issue, like perhaps the filter?

 

02 is something that doesn't come into play until warm and typically active under load..

 

Good call... didn't even think about that.

 

Could be a TPS.

 

I like that, warm and underload are important here. Do I need my O2 sensor? I'll do some searches here.

Still open to ideas, THX...

 

EGR valve, could be sticking open or not closing fully. Or, the EGR valve has moisture in it. It will run rough like that if it does, till it sucks it all through. A small vacuum leak might also do the same.

 

OK, so I got under thr truck this weekend and found that the 02 sensor was wrapped up around a frame support instead of being in the exhust pipe like it should. Seems the PO took it out (or it rusted off/out) and put a patch over the pipe.

Now, here's my question, without an 02, how was my truck running perfectly all winter long? i've got a pipe and a new 02 on order and should have it on this coming w/e, with a progress report to follow...

 

Might be that in winter is was cold enough to need the excessive amount of fuel that was being provided.

The real question is why weren't you setting a code? Check engine light on?

 

check engine light only recently started to come on and was imtermittent, I have not had the codes checked...

 

Just put on a new pipe from the header back w/a new O2 sensor. It's running like a top now. I guess it was the change in the weather, warmer, that exposed the lack of an installed O2 and brought on the stumble/hesitation...