weird problems, idling up, and down

[toyotatuner]

I need some help guys, I think I messes up something, but not too sure what it is when i went "puddle jumping" this weekend :) . I noticed wheni was parking later that the idle was going up, and down, from too fast to too slow, really weird, so i traced all the hoses etc looking for a vacuum leak, to no avail. Then i stared pulling hoses, checking for suction, BAM, i found it, the vaccum line coming from the brake vaccum booster. With the engine running and hose connected its fine, when the engine is running brakes depressed, i get a funky idle as described. With the hose disconnected, i get a low idle, with the hose disconnected, and brake depressed, no effect to the idle, cap the hose, and the idle does the same as described above. Any ideas anyone, i dont want to have to replace the vaccum booster unless i really need too, this is the top suspect though....
please someone, gimme a little advice.
Oh, 1990, toyota p/u, 22re, 5spd
thanks
-John

[TrucksChixnbeer]

iwould just pull our disputer cap and check for water

[toyotatuner]

will do, any other ideas?
the brake vaccum booster is 250!!!OMG!

[22REkid]

I have had the same problem with my buddys truck and every time I pulled off the booster hose it quit doing it. So we replaced the booster and guess what... it still did it. This same problem has been discussed a lot lately. IAC valve. I believe there have been 3 people on this board in the past month who have had this problem and I told them all to do the same thing. Pull off the intake tube and put a piece of tape over the 2 holes inside the throttle body and set the idle accordingly. Trust me, just try it.

[toyotatuner]

thanks, i just re-read all the posts on that "IAC" sounds like a suspect too...only thing is it runs fine any time the accelerator is depressed. well, not noticebly worse. So, i CAN clean this? If so, i need to use an O2 sensor friendly solvent?

[87FOURjogger]

what he said works for me. i just pulled the hose and taped it off.

[22REkid]

For the record, I am not the guy who said you can clean it. I guess it is possible since it has worked for him. I also had another friend who had the same problem and the coolant line going to the IAC valve had some sealer in it and it was blocking the line preventing the wax element from ever getting hot and expanding, we blew through the coolant line with compressed air and the blockage came out, we put the coolant line back on it and it has worked fine ever since. I think that the reason that it will idle good when the brake booster is unplugged is because since the system is under a big vacume, when you pull the line it creates a big vacume leak and takes away the extra air going into the TB. A good running engine will also run fine with the booster line removed. Believe me I battled this problem for a long time until I figured it out. In the process I replaced a fuel pressure regulator, MAF, TPS, brake booster and even an ECU to no avail. Try to plug the holes with tape.

[toyotatuner]

so, i should pull the intake hose, tape the 2 holes, and adjust idle? why should i need to adjust the idle it ran fine before all this....and should i leave the tape permanatly?

any other ideas?

thanks,
-John
(thanks you guys, im going to get started on this this afternoon, and hopefully have a good report tomorrow)

[22REkid]

so, i should pull the intake hose, tape the 2 holes, and adjust idle? why should i need to adjust the idle it ran fine before all this....and should i leave the tape permanatly?

any other ideas?

thanks,
-John
(thanks you guys, im going to get started on this this afternoon, and hopefully have a good report tomorrow)

Sometimes you have to adjust idle afterword because now the fast idle is bypassed resulting in a lower idle than before. The tape is only meant to diagnose the problem, if the tape fixes it, buy a new IAC valve which might be a discontinued part. There is nothing wrong with leaving the tape on there if you find out that the IAC valve is a lot of money, just make sufe you use a strong enough tape that will not get sucked into the intake (duct tape works good). If it is idling above 1100 there might not be a need to do the tape trick, just lower the idle.

[toyotatuner]

well, guys, no news today, i was busy working on the front end last night, new inner & outer tie rods, lower ball joints, bearings/race/seals, pitman, & idler arm, wow, it was toast!
(boy i really kicked myself for spending this much, i couldhave been 1/2 way to SAS, damn, oh well, i just bought new 31 BFG's and want to keep em for a while.) Still, if you guys have heard of ANYTHING not mentioned here, im game to put it on my list of things to test. thanks again everyone for being so helpful.
-John
BTW, a pitman puller will pull all the tie rod ends and ball-joints, waaay better than slamming into your knuckle with a pickle fork. got mine for 19.99 :redspotda

[TheFatKid]

ok here is something to check out
on the v6 toys the manufacturer ran the break lightswitch tothe ecm and then to the brake lights
so when you step on the brakes the ecm senses that you are slowing down and will not need to accellerate.
it kills the injectors untill the RPMs are at or below idle then turns the injectors back on.
to test if this is the problem unhook break light switch and step on breaks and see if it does it.....
if so you can trace the wirering back to ecm and find out what ones go to break lights and splice them together to cut the ecm out of the system or find out why you idle so high and fix that.
Also try putting it in 4wheel drive and see if it does it . On mine it wont do it with the breaks depressed.
i have that problem with my 89 v6 toy and I didnt fix it right away now my truck does that idle thing most of the time so im going to try some of these tricks hehe good luck

[87FOURjogger]

covering the iac valve holes worked for me. whats the permanent fix? replacing the iac valve?

[22REkid]

ok here is something to check out
on the v6 toys the manufacturer ran the break lightswitch tothe ecm and then to the brake lights
so when you step on the brakes the ecm senses that you are slowing down and will not need to accellerate.
it kills the injectors untill the RPMs are at or below idle then turns the injectors back on.
to test if this is the problem unhook break light switch and step on breaks and see if it does it.....
if so you can trace the wirering back to ecm and find out what ones go to break lights and splice them together to cut the ecm out of the system or find out why you idle so high and fix that.
Also try putting it in 4wheel drive and see if it does it . On mine it wont do it with the breaks depressed.
i have that problem with my 89 v6 toy and I didnt fix it right away now my truck does that idle thing most of the time so im going to try some of these tricks hehe good luck
I've never heard of that and I don't think it has anything to do with the brakes. On most port injected vehicles when the manifold pressure gets too high, the computer will shut the injectors off relying on information from the MAP sensor (Manifold Absolute Pressure). The injectors will only turn off on deceleration when the engine is not being accelerated.

874JOGGER,
You can leave the tape on there no problem but if you want you can replace the IAC valve. Not sure how much they cost.

[toyotatuner]

which holes, i see 3; 1 larger hole, 2 smaller, the larger is on the lower area of the front portion of the intake manifold, and the 2 are on either side of the intake (r/l). thanks.
-Johnny

[toyotatuner]

im running: 22re, 5spd

[22REkid]

plug the ones off on the inside of this mechanism
http://i79.photobucket.com/albums/j127/22rekid/567.jpg

[toyotatuner]

so thats the iac valve?

[22REkid]

No, do you see the line coming off of where the circle is? Follow that line down and you will find the IAC valve, there should be a coolant line going to it. The area circeled in the picture is where the air goes through the holes in the TB. Block off those holes. Your TB is different than the one in the picture because it is a 1986 but they all work the same.

[toyotatuner]

:redspotda
:redspotda :grin:
duck tape is the shizzile!
It worked guys, I have to admit at first i had my doubts, but the tape blocked off the excessive vacuum, engine runs fine, even back to norm idle. :redspotda
I guess this weekend im gonna try and blow a little air through the coolant line and hopefully fix it, i called a couple of parts stores around here (hilo, HI) and it runs about 225 smakers, geez. :thumbdown
thats last resort , anyone got one from a 1990 22re?(Cal. Emissions)
thanks!
-John

[toyotatuner]

Ok guys/gals, I just wanted to follow up let everyone know how everything panned out. This weekend, I removed the 2 coolant lines to the Air Valve (as described in the Haynes Manual; Fuel & Exhaust Section) or the IAC valve (Idle air Control) same thing. I noticed quite a bit of crud lining both the upper & lower hoses, the lower line had a bit of collant pressure when i removed it, maybe i should have drained some coolant, i just pinched the line and closed it off with a zip tie though. pretty basic, blew some air through into a pan, man what a bunch of crap came out!!! re-connected the lines, BAM, she runs like a champ. All day on the trail sunday, no problems, just kept poking along, woohooo! Thanks agian for all of your help guys, it should hold out for a while.

[anklenawer]

well i have the same problem...

two things. i can't turn the idle down any more.. its all the way in... im not thinking thats a good deal..

so im going to do the IAC valve deal...

but im not great with automotive work - i got the haynes manual though -

so i take off the air valve-throttle hose
the coolent hose and another air hose.. then clean the air valve?.. with what.

do i just run air through the hoses when they are off?... is there any spay cleaner to clean the air valve?... any help would help me out gents... im gonna go to the auto port today to test the hoses and make sure there are no leaks in the air hoses...

[22REkid]

well i have the same problem...

two things. i can't turn the idle down any more.. its all the way in... im not thinking thats a good deal..

so im going to do the IAC valve deal...

but im not great with automotive work - i got the haynes manual though -

so i take off the air valve-throttle hose
the coolent hose and another air hose.. then clean the air valve?.. with what.

do i just run air through the hoses when they are off?... is there any spay cleaner to clean the air valve?... any help would help me out gents... im gonna go to the auto port today to test the hoses and make sure there are no leaks in the air hoses...

The valve itself is made of wax that expands when it is hot to stop the extra air from going through the throttle body via the holes in the TB. Pull the coolant line off and spray compressed air through the coolant line, it's most likely a blokage in the line preventing the wax from getting hot and expanding. Don't blow too much through the valve itself or you might mess up the wax element and it will never work right again. Try the tape trick first just to verify that it is actually an IAC issue. If the idle screw is all the way in and the holes are covered it might not want to idle when it's warm so you might have to agjust it.

[anklenawer]

:redspotda

http://img178.imageshack.us/my.php?image=dsc02573gn4.jpg

this is my throttle body - obviously.. but i see in the haynes manual there should be a hose commin down from there that i don't see in mine...

but anyway - i took the hoses from the air box down to some metal piece i took a pic of here - http://img90.imageshack.us/my.php?image=dsc02577jt4.jpg

and just made sure they weren't clogged or anything -

btw.. thanks for your help guys..

take care -

kyle

[22REkid]

There should be a hose connected to where the yellow circle is. That is the reason why the idle is turned all the way down and you still have an erratic idle. That is a big air leak and your problem. If you can find the hose that goes there, reconnect it or if you can't plug it off with a vacume cap or tape and set the idle right. As soon as you plug off where the line is supposed to go it probably won't idle of the serew is all the way in.

http://i79.photobucket.com/albums/j127/22rekid/dsc02573gn4.jpg

[anklenawer]

welli checked around for a hole or anything on the throttle body - and i couldn't find anything!.

the side the picture was taken on...there isn't a hole or anything that i could find.. im going to post more pics/closer pics to show you gentlemen.. i cleaned the throttle boddy a little with the TB cleaner... and i really didn't notice a difference

but it drives.. and doesn't stall!.. so i will contine the driving

take care - thanks for the help you yota brains out there

keep lookin for pics later today

[anklenawer]

ok.. from pic 1 to the second picture , there is a hose... im not sure if this was the hose from the throttle body to the air valve but.. i took the hose off and it was black.. it tasted coolant when i blew threw it. the second picture is where more clean coolant was.. i tried blowing in it.. not hapening - isucked in.. and just a little came out.. that was green - in picture one - that section was like death valley - it was black.. gritty - ( one off the throttle body) and wouldn't suck/blow anywhere.. maybe i need an air compressor..
but .. is that what i need to run compressed air through?

help me out -
thanks for everything so far
pic 1 [img=http://img46.imageshack.us/img46/151/dsc02595ix9.th.jpg] (http://img46.imageshack.us/my.php?image=dsc02595ix9.jpg)

pic 2 [img=http://img337.imageshack.us/img337/9678/dsc02599sl1.th.jpg] (http://img337.imageshack.us/my.php?image=dsc02599sl1.jpg)

[anklenawer]

i just flushed my radiator.. at first.. it didn't do anything to the idle... but then wheni got home.. it was good.. for now..

it is a warm day - and when its warm out - it doesn't do it that often - we will see tonight - but like i said.. that hose was damn near black fluid ( i tasted antifreeze) it was just really rusty =

any ideas give me a shout

[22REkid]

put a piece of tape over the holes in the TB and set the idle. It'll work just fine.

[anklenawer]

i don't have any holes in the throttle body tat are visable

[22REkid]

i don't have any holes in the throttle body tat are visable

These ones.


http://i79.photobucket.com/albums/j127/22rekid/dsc02595ix9.jpg

[anklenawer]

dude, alright, i taped both of the holes... and it would start, but not hang on long enough to even rev it up.. it would just die... the small hole ( uppper left) is for the idle adjustment - so i untaped that... leaving just the big one on the bottom.. that worked just fine.. i adjusted the idle... and no more surging - ... one problem though, it has so much suction.. the tape had a hole in it and it went crazy again

so before i get a more secure fix.. that will probably be more long term.. what am i actually doing to my truck?.. haha.. i don't wanna hurt it and this just seems like its not a "safe" bet.. but hey, if it works.. im in!

just tell me what im doing

thanks guys for all your help...

[anklenawer]

so anybody.?


i went to hollywood today.. and i twas hot as hell.. like 93 today..

it didn't act up at all, i noticed that.. that in hot weather..outside - it does'nt do it. but the cooler it is outside, the more it acts up..

that should narrow down the problem

later dudes

[stump runner]

dude, alright, i taped both of the holes... and it would start, but not hang on long enough to even rev it up.. it would just die... the small hole ( uppper left) is for the idle adjustment - so i untaped that... leaving just the big one on the bottom.. that worked just fine.. i adjusted the idle... and no more surging - ... one problem though, it has so much suction.. the tape had a hole in it and it went crazy again

so before i get a more secure fix.. that will probably be more long term.. what am i actually doing to my truck?.. haha.. i don't wanna hurt it and this just seems like its not a "safe" bet.. but hey, if it works.. im in!

just tell me what im doing

thanks guys for all your help...


22rekid writes on pg 2 of this thread "Try the tape trick first just to verify that it is actually an IAC issue."