93 .22re high idle,and pulsing whene brakes on

[frogger]

hi all.. i have been researching my idle issues for weeks now on this forum.it started with the idle pulsing up &down whene the brakes were on.
i read on here that i should turn down the idle screw until the eratic ideling stopped .. i did this and it worked fine . i removed the throttle body this weekend to clean out the carbon on the other side of the butterfly i used carb cleaner ,seafoam ,smallwire brush etc.etc sprayed out all the vacume ports
new base gasket.i took very good care of my throttle body .after re-installation the motor ran great at the marm up high idle for about 8 minute then the idle slowly came down to about 1500 and would not go lower so i turned in the idle screw slowly and the idle lowered until the idle screw bottomed out .the idle is still high at about 1200.
i checked everything i messed with and cannot find a problem.i even shut the motor off for 5 mins re-started and still the same issues and now the pulsing is back wene the brake is on...HELP!!!

 

[turboSR5]

Sounds like a vacuum leak. Make sure your elbow is not leaking at the throttle body or further upstream. Check your vacuum hose diagram for routing and inspect each hose for fit and leaks.

 

[the_dingman]

It's a vacuum line problem 100%. I had the same issue with mine after I accidentally swapped two vacuum lines of the same size. I don't recall which ones.

 

[fourwd1]

I can't tell you why the idle is higher, a lot of possibilities after the service.

But when the idle is too high like yours, the idle will pulsate when the brake pedal is depressed. The ECM fuel cut circuit is confused and cutting off and on.

 

[frogger]

thanks for replying guys . i have inspected everything again and cannot find any vac leaks :wtf:
i am gonna pull the throttle body again and see if i missed something .could the throttle position sensor be causing this? it doesent appear to have been moved.by the way ..what is the idle-up valve and does it mean something is wrong when turning the adjusting knob all the way in or out and nothing changes?? somebody s got to know .

 

[turboSR5]

thanks for replying guys . ..what is the idle-up valve and does it mean something is wrong when turning the adjusting knob all the way in or out and nothing changes?? somebody s got to know .

On your 93 the IACV (Idle air conotrol valve) is a cast piece with a couple of hoses running into it. If you want to test if it is stuck open you need to warm the truck up for at least 10 minutes and then tape off the large hole on the bottom, inside of your throttle body (be sure you clean the area you are taping very, very well and use some Gorilla tape!). If your IACV is stuck open the idle will be much lower once you restart your engine. If it seems your IACV is stuck open then remove the TB and seperate the IACV. Look inside the bi-metallic spring and see if there is anything in there that is jamming it up, clean it all out with TB cleaner and give it another try.

The reason your Idle screw in not adjusting is because you have a leak somewhere in the intake system or throttle body. The screw will only control the air that comes through the passage below it, it can't adjust for additional air moving through another location.

If you want to go deeper, Google "4x4 wire 22re IACV". There is a neat thread on there that covers pretty much everything and then some.

 

[frogger]

just finished pulling the throttle body off and removed all the guts of the IACV. the steel pin that is inside the brass bottom piece came out and got lost for 10 minutes on the ground.is there a spring in that brass piece ???? i hope not cuz its gone!!
i put it back together and started her up and it still has the same problems . i checked all the intake and vac lines and cant find the air leek.
tomorrow ill pull the tps and do some testing.
by the way the coolant level is normal but iam hearing the gurgling sound from behind the dash .is that trapped air in the coolant lines?:lasercannon:

 

[sugarshack]

sounds like a vaccum leak alright... ...but if it happens only when you are breaking, it has to be in your power-booster leaking. or the hose to it.

 

[frogger]

I fixed the high idle problem

:driving: WELL TO WHOM IT MAY CONCERN MY THROTTLE BODY ISSUES WERE ALL DUE TO A BADLY WORN OUT BUTTERFLY VALVE !!!
I CLEANED IT AND IT SUCKED TOO MUCH AIR PAST. I TESTED THE IACV ,THE THROTTLE SENSOR THE AIR MASS METER ......ALL CHECKED OUT GOOD, BURPED THE COOLING SYSTEM AND STILL HAD THE PULSING &HIGH IDLE.I TOOK THE 4RUNNER TO MY MECHANIC WHO USED TO WORK FOR A TOYOTA STEALERSHIP HE PUT ON A USED THROTTLE BODY ON AND MY RIG RAN GREAT ..HOPE THIS HELPS SOMEONE WITH SIMILAR ISSUES.:flamethrwoer2: