ignatz

Hi. I'm having a problem with high idling. The closet match to my problem is described in this thread here
Specifically, my truck seems to run fine until I come to a stop. When I come to a stop, the tach goes to ~2000 rpm and stays there until some time later when it slowly comes back down to ~1000. I checked for vacuum on the 3 throttle body ports which seemed fine. I checked the TPS today and it's fine. I ran into questions with the dashpot. Mine is missing the cap, separator, and filter. The dashpot also seems to be full of grease and grime. Could this be the source of my revving problem? Should I replace or clean the dashpot?

Also, what is this thing?


http://www.flickr.com/photos/8439710@N05/3590710066/

I haven't noticed this in other engine pictures and couldn't find anything in the FSM.

Edit - Added link to flickr for photo. Don't know why it didn't work with the IMG tags.

Junkers88

That thing in the link looks like the top of the PAIR valve, it puts clean air into the exhaust to help with emissions.

If the dash pot is all clogged I'd say take it off and drive without it for a while and see if that helps. If it doesn't change anything then post back up. High idle is a demon that a lot of us are chasing right now, we'll do what we can to help.

ignatz

Thanks very much! I followed your advice, I eliminated the dashpot from the equation (removed the adjustment screw altogether) and confirmed that it was causing a temporary high idle. Once the truck is warmed up, it idles constant at about 1250 rpms (still a little fast, right?) until I press and hold the brake. While the brake is pressed, the truck's idle bounces from 1250 to 1000. It kinda sounds like it almost stalls. I'm guessing there is a vacuum leak somewhere but I'm at a loss as to where... back to the FSM. Any hints or tips for troubleshooting a vacuum leak associated with brake pressure?

ignatz

I found this post which suggested that the brake surge might be caused due to the high idle so I tried to adjust my idle and found that 1250 is as low as I can adjust it. I tested the brake booster using the FSM routine and it passed both operational and air tightness tests. I'll keep reading/searching but I'm at a loss so any help/tips are much appreciated.

Junkers88

Before you start chasing a vac leak you need to do two things.

1) Set the idle to 750rpms when it's warm

2) Make sure the timing is set properly at 5 degrees Before Top Dead Center.

I had a strange issue a while back where the idle on mine would surge when the brakes were applied. It was going from about 1000rpms to 1500rpms. The reason is surges is because of the higher idle. Now if I recall this correctly, when the brake is applied the ECU cuts the fuel/idle assuming that you are coming to a stop. When the idle goes back up (due to it being set too high at the adjustment screw), with the brake still pressed, then the ECU again cuts fuel to drop the idle..... over and over again.


edit: I think we were typing at the same time.

Check the timing and adjust it if need be. You might also take a rag with some brake cleaner on it and clean out the throttle body. If there is a line of crap around where the butter fly valve is supposed to seal then it will stay open letting more air into the system and making the ECU kick in more fuel to compensate.
Do those two things above first and then get back to us.

ignatz

Thanks again! I have more questions of course!

1. I tried to adjust the RPMs but the lowest I could set it (with no diag jumpers in place) was 1250. The idle adjustment screw won't go in any further. How else should I adjust the idle?

2. I tried to check the timing but when I put the TE1 to E1 jumper in place and the engine was warm, the RPMs settled at around 1010. The FSM says it should be 750. The info plate under the hood says a 4x4 should be 850. Will my timing checks be accurate even if I can't get the proper RPMs? What can I do to adjust the RPMs while the diag jumper is in place?

I have a basic question about checking the timing. Should I be checking it with no belts in place. I attached an inductive timing light to the battery and to the #1 cylinder's spark plug wire. When I try to shine the light on the timing plate the belt covers it and I can't make a reading. I'm not sure if there's a trick to it.

Edit - Yeah I think you're right. I just read you edit. I'll go try to clean the throttle body next. Thanks!

desertcamper67

How do you adjust the idle on the 22RE. I just popped in and thought I'd check with a live person.

ignatz

You adjust the idle but turning a flat head screw that is located (when facing the engine from the front bumper) down and to the right of the throttle. On top instead of on the side of the throttle body.

Junkers88

Hey did you clean the throttle body and get any results? If we can get your idle back down to 850 (for a 4x4) we can check that timing and then readjust from there.

desertcamper67

Thanks. I haven't had to adjust that since my last '85 4Runner. It was such a PITA that I must have temporarily forgotten where it is.
My last one was so frozen that I had to take a die grinder to the head and cut a phillips slot into it then use a impact driver to get it to free up. That and lots of P.B. blaster.

I just adjusted mine minutes ago and it went so smoooooooooooth. Like it could fall out by itself. Anyways now I'm ready to go to the smog shop again. Yesterday he wouldn't test it because eh thought it might be a trap vehicle with the header and no c.a.r.b. number visible, high idle and so old. That was a test only station so he didn't fail me.. Thats good.

ignatz

@desertcamper67 - Glad to hear it helped out. Good luck with the smog shop. California emissions testing sounds like a PITA.

Junkers88 - Thanks again for the help. Sorry I wasn't able to respond sooner. I got rained out yesterday afternoon. I woke up early this morning and tried your advice, I cleaned inside the throttle body and around the butterfly valve (without removing the TB). I also removed and cleaned the idle adjustment screw to make sure it wasn't binding. After all of that my idle is about 1250-1300 rpms now. Interestingly, if I turn on the AC the idle drops to 980-1000 rpms.

Junkers88

That idle is still to darn high.

Have you tried to time it again? I know you said you couldn't see the mark when you tired it before so you'll have to reach in there and clean off the timing marks on that little tab and then see if there is still that little white mark on the crank pulley.

Crap if you were closer it'd be easier for me just to show up and help instead of typing and waiting.

Oh and don't forget the jumper when you time it.

desertcamper67

It is. Fingers crossed. I threw in a bottle of that CRC pass emissions or your money back stuff in there for good measure.
It's worked for me in the past. When I would barley fail, it would clean things up enough to pass.

ignatz

@Junkers88 - Thanks again for all the help. My neighbor stopped by while I was working on my truck and asked about my problem. To make a long story short, he pointed out that I wasn't actually adjusting the idle screw. The idle adjustment screw has a spring underneath it and has a plastic head. I'm not sure what screw I was turning but there you go. My idle is now at 830 - 860. The motor seems to be running much rougher than before. The RPMs with the AC on are around 500. I'm going to continue working on checking the timing. I'll remove the belts and clean the timing plate to make it more visible. I'm still not certain where I should hold the light so that I can timing plate and mark without it being obscured by the belts when they are in place. Is this a common problem?

Junkers88

Where is that Face Palm picture when I need it???

I'm glad you got it figured out. You should hold the timing light directly above the timing plate, pointed straight down. It's a little bit of a pain if you're short or have a lifted rig but it can be done. I'd bet dollars to doughnuts that the idle gets better once it's timed.

On the AC I think there is a valve or switch or something that is supposed to make the truck idle faster when the button is pushed. I'll have to do some looking.

desertcamper67

Well my rig failed smog. This is a huge setback. Now I need to find a new thread that deals with my high "NO." reading. I don't know what that is. Nox? something like that.
Oh well, here we go again spending $$ I don't have.

toyota4x4907

PM sent.

desertcamper67

Thanks. I started a new post about these couple of issues I'm having.