Hey there so I thought I had my 94 runner with 22re figured out after adjusting tps to spec. I’ve now also adjusted my timing to spec and have no codes.

On cold starts the truck starts up easily idles high and then drops to 750 once warm.

If I take it somewhere and turn it off and leave it come back a while later like an hour it starts up and levels off quickly at 750

If I drive it somewhere shut it off and then shortly after get in and fire back up it idles low. Like 500-550. I give it a little gas and shortly after it’s back at 750 give or take.

It also tends to have a bit of a gassy smell on most (maybe all) startups. I’ve read this could be the egr.

I had attempted to pull the manifold to clean it but snapped one egr bolt off the intake and stopped there not having a replacement bolt.

BTW it was doing the low warm idle before that so it’s not due to a leak.

Im considering getting the bolts and trying to pull the egr to block it off and test it. Just a little concerned that I won’t be able to get the bolts out of the intake and since it’s an awkward place they’d be near impossible to get out without pulling the whole intake. (The second bolt felt like it was gonna snap when I tried to loosen as well)

Do I leave well enough alone and get used to giving her a little throttle on warm starts?

I wasn’t brave enough to snap the other bolt off because I couldn’t be certain it would break the same as the first. The broken bolt would most likely be accessible to twist out with a pair of vice grips as it was mostly the head that came off. However if the other one snaps deeper in then I’ll have to pull the whole intake and drill and extract what’s left of it. (If I’m lucky that’s what will happen.) or it might come loose without snapping but it had that metal twisting feel not the tight and unthreading feel. I’m guessing it’s the aluminum intake plenum seizing to a stainless bolt attached 25 years ago.

Please keep us updated if you figure it out. I have the same exact problem and have tried many things but the low idle at warm startup still exists.

My upper & lower intake was off at one point and I got them hot tank cleaned. This did not help the issue.

Same thing happens on my 92 22RE. I just live with it now. It does not happen all the time anyway...just randomly.

Blocking off EGR will not fix the problem either. Been there and done that. New idle air valve installed too which did fix the random high idle.

I do believe it has something to do with the air flow meter, but I am not messing with the AFM until it blows!

Have you tested yours? I did have some open spots between E2 & Vs when moving the vane on mine, so bought a re-manufactured one. That one also had open spots, so I returned it and am still using my orig one.

Testing the VAFM: http://web.archive.org/web/201209071...33volumeai.pdf

Thanks Paul. Looks like I can check off cleaning the intake and as per below probably not the egr.

I checked the VAMF or whatever it’s called MAF laugh laugh. To the recommended specs functioning properly.

Maybe a thermostat thing? I understand there’s a few that could cause the issue.

My Haynes manual said something about the charcoal canister being responsible for the fuel smell. I’ll chexk into that at some point.

For today I finally got the front grille off and painted the bugger. Also finished off the rattle can on the front end which I had treated for rust. Looking much sharper.

My passenger side cv boot finally blew up a couple months after I replaced the drivers side with a dorman split cv boot which is holding up fine. I’ll be doing the same on this one till I have the money to replace the cv axles which sound like they need it! I also added a line of black silicone to the seam of the split cv since the mini bolts were about 50% effective. And used threaded hose clamp instead of the ˟˟˟˟e tough to use rachet style included in the kit.

Next up is tires since the ones on it are scaring me with looks of dry rot. Or wheels and tires wheel see what shows up on the list.

Might be a silly question but what does everyone use to clean up the intake etc? Electric parts cleaner? I have gone through cleaned my TB and all the metal bits, replaced gaskets, replaced vacuum lines that were cracked, and mine still sits at 500RPM with a slight stutter at idle.

Anyone got any ideas? Ive just been rolling as is either give it some gas till it idles up or start it with the ac on then it idles 750 till it figures itself out.

I’m guessing it’s some kinda thermostat temperature thing but i dunno where to start checking.

FPU (fuel pressure up system) switch on top of the thermostat controls the vacuum switch valve to the fuel pressure regulator. This gives slightly higher fuel pressure for warm restarts.

There is a TSB relates to this, both switches are discontinued from the dealership.

You'll also need to dig into the throttle body and idle valve.

Yikes Ok, sounds like maybe best left alone? Is there anywhere to read the TSB and get the part numbers? Maybe I can find them used or figure a work around once they’re tested.

Thanks again for all your help the truck is running great compared to when I got it.

My fuel pressure regulator gets vacuum straight from the upper intake vacuum three way fitting. Yes I bypassed all that other stuff. Don't see how a fuel pressure up would do anything for my truck.

It's similar to the coldstart system in that it provides more fuel during start up in conditions the coldstart system isn't active.

...

Anyways it's just one part of the equation. It's all about air and fuel in the right proportion at the right times.

If you do not have air leaks, if you don't have leaking injectors, if your throttlebody functions repeatably, and if your idle valve functions correctly.. You have faulty sensor data most likely, which are typically due to bad power and ground or faulty connection or wires.

Clean the power and grounds.
Clean the coolant sensors and their mount points.
Inspect the throttle body and idle valve, insure you have a good oring on the idle adjustment screw.
Inspect the vsv's (these are detailed in the manual).
Replace or clamp loose vacuum lines.

Except for that last one these are all simple tests and only take man hours and not part swapping. Testing and inspection not guessing and throwing parts at a problem work very well.