The Idle seems to stumble once in a while.
I notice its fine when she has sat over night or for a long period of time.
I can start it up in the morning runs good idles great, idle comes down once the temp start to come up and runs fine. I can drive it for short or long trips runs great but every now and then I shut it off and go to start it and the idle is realy rough. It will even stumble, stumble and die, I restart same problem. I give it gas and let off still the same, stumbles and dies. I give it a good rev to like 5000 rpm and it seems to work but it still is not right, the stumbling is still there. Some days it's good, some days not.
What is the problem? I'm thinking some type of a sticky choke or weird vac leak. Any ideas?

It's a 1991, 4Runner, 3.0, auto, 4x.

 

maybe your EGR

 

try doing a basuc tune up...plugs, air filter, oil change,adjust blets...clean the TB or carb...try seafoam it works

 

I have something similar, my idle is often really low if I start the engine warm, probably 300-400 rpms or so. Haven't tried to figure out if anything is wrong though. There's always suggestions on what to try to do to fix things, but there is pretty much always a (logical) explanation to the problem, and I bet there is one here as well.

 

I had a similar problem and after installing a new Denso O2 sensor, the problem lessened significantly. Every now and then, it will stumble after a warm restart, but will no longer stall out.

Check these threads out:

https://www.yotatech.com/forums/show...t=warm+restart

https://www.yotatech.com/forums/show...t=warm+restart


Troy

 

Could be any one of what the guys above me mentioned. Could also be some moisture under your cap or some condensation in one of the plug wires. They are a cheap part so I would start there.

I have a similar problem that was condensation under my wires, it would stumble bad when I gave it gas after a cold start up. Has since gotten way better since I changed the plugs, and wires. Everything is smooth again.