I took my truck on its maiden wheeling voyage two days ago. It did great until the muck puddle. I figure the puddle was at least two feet deep, but I was able to power thru it and did not stop. Right after my truck would not idle, or idle really low 300 - 400 rpm and stall.

I stopped and looked things over, the front of the engine and the radiator had muddy water on them, but everything else appeared okay. I pulled the cap, dry. Pulled the air cleaner cover, dry.

I drove the truck home and it would not idle when I stopped or shifted. It seemed like it was backfiring when I would shift, or slow in a gear.

When I got home I cleaned all of the mud off and cleaned the motor. I changed caps and made sure everything was dry. I cleaned the carb, checked all the vacum lines, checked the timing, had the coil checked, everything appears fine.

Still wouldnt idle.

Here is the real stumper... I took it into my mechanic today, he looked at it and let it run for an hour without a problem. I test drove it for 10 min or so and it was fine. Went back later this evening to pick it up, and back to square one, wont idle right and dies.

Any help? Its a 1985 and is carburated. It has 102k

Thanks

 

darn. Thats a tough one. I'll tell ya though, check the engine fuse. I know its a long shot, but check that first, we'll go from there.

 

How hard did you POWER through? Sorry... I'm assuming head gasket failure. Probably not... but my truck ran like crap when the head gasket leaked and that will happen if the motor gets hot because of powering through things

I would say small vacuum leak, but if it ran fine in the shop then I don't know what to think.

Is there a vacuum port that opens up when a motor warms up? They're might be one or two in the AAP system for cold-start.

Lastly, is the mechanic a good mechanic? I've met those mechanics that "take a real good look" for about 5 minutes.

 

Update!

Thanks for the responses. I dont think head gasket, coolant is full and temp gauge is okay. Didnt power thru that hard, I think the highest I saw my tach go was 4k. Just meant that I didnt hesitate once I dunked, was in and out as quick as I could.

Went to the mechanic again and he didnt have a chance to look at it. I offered to drive it around until the problem surfaced and bring it back in and he agreed. Sure enough it started to idle like crap, but it wouldnt stall, just idle around 400 rpm's. He adjusted the idle mixture and revved it up and now it seems ok, but not great. He seems to think there is some crap in the carb and needs to be flushed out. He didnt charge me for anything, nice guy. How well does he know Toy's?

Any thoughts on the idle mixture adjustment? I have a feeling that it compensated for another problem, but again, it seems to run okay.

Also, how do you know if the AAP has an issue? I pinched the hose during warm up and it wanted to stall. After it was warmed up I pinched it and it didnt do anything.

It is a California model with the extra emission crap on it minus a CAT (still passed emmisions).

 

Oops, my bad. lol Must be the dyslexia. Squeezing that hose will either make it stall when its cold or when its hot. My choke system doesn't even work and that fitting broke a LONG time ago

I would have to go back to the carburetor then. Funny... I've gone through some deep stuff but never had a running issue afterward.

It might be worth it to rebuild the carb if the kit isn't expensive.

I don't think the EGR valve is hard to remove, and I remember reading something about a filtering screen. Might be worth checking out? Also, you should have a cahrcoal box or somethign similar that connects to your intake hose near the firewall. Check that as well as the reservoirs that connect to the fuel line. There's atleast one, my CA truck has two, whcih have something to do with fuel recirculation or EGR. I don't even know, maybe they're charcoal canisters.

 

Update -

I've been driving the Toylet for a few days after the idle mix adjustment and it seems to run ok, however it backfires when slowing in a gear, or between gear changes. I know I have an exhaust leak at the manifold where it connects to the piping (feel air at start up), but I have a feeling there are other issues. One of my BVSV valves is missing the cap, I called the stealership and they want $75 for the part!

Anyway, any additional help would be appreciated. Thanks.

Hate to say it, but my Jeep Cherokee was ran way harder and I never had issues with it. Hmmm......

 

Assuming a 22RE engine?

Check the dashpot on the throttle linkage, it keeps the throttle from slamming shut and causing backfires:
- http://www.4crawler.com/4x4/CheapTri....shtml#Dashpot

The thing inside the green circle:

 

No, its got a carb. Any other ideas?

Thanks.