toyinhawaii

Hi all..on the 03 taco 3.4l prerunner automatic 4door....how is the adjustment on the tps done???..

Thanks

DailyDrive

Can I ask why do you think it needs adjustment?

toyinhawaii

BEEN TRYING TO GET THIS TO IDLE AT SPECS FOR A COUPLE WEEKS...IDLE IS 750(-+50)
IT SITS AROUND 650..I ASSUME...THE TACH MARKS ARENT NUMBERED SO BETWEEN 0-1000 RPM I'M GUESTAMATING...IT IDLES JUST ENOUGH WHERE, ITS A LITTLE ROUGH..TIMING IS PERFECT..ADJUSTING THE THROTTLE CABLE, DOESNT SEEM TO WORK. THE TPS,MAF,A/F,OXY SENSORS ARE ALL GOOD (IN SPECS)..WHEN I DO ADJUST THE TPS I NOTICE (SOMETIMES..IT HAS A CLICKING SOUND..LIKE THE ECM IS TRYING TO RE-ADJUST IT OR SOMETHING..I HEAR THIS ABNORMAL NOISE ONLY FROM THE TPS..I'M THINKING I MAY NEED TO TREAT IT LIKE I'M CHECKING THE TIMING...ENG. WARM,NEUTRAL, AND THE connect terminals TC and CG of the DLC3...AND THEN ADJUST IT...CANT DO THIS NOW..AT WORK, AND JUS BRAINSTORMING. BEFORE I WAS JUS LOOSENING THE SCREWS AND ADJUSTING..SOMETIMES IT WORKS FINE..BUT THEN I NOTICED AFTER I TURNED OFF THE ENGINE AND RESTARTED IT READJUSTED THE RPMS AGAIN..YES I DID TAKE OFF THE NEG. BATT. TERM. SO THE ECM CAN CLEAR AND RELEARN..(MIN.15 MINUTES)..THERES MY STORY..SORRY A BIT LONG ..THATS WHY I JUST CUT THE THE POINT ON MY FIRST THREAD..THANKS

Godzilla

There is no adjustment on the TPS.
Also, the FSM has the idle @700+/-50rpm in N, A/C off
If anything, clean your IAC

toyinhawaii

Sure there is...if u loosen the 2 screws and turn the tps clockwise/counterwise (just a couple hairs),it will bump up or down the idle..i dont have the iac version..i got the control motor one...and checking the specs w/ohms,....its all good

86-91-4runners

I do not know if they are the same, but the TPS on the 3.0 if I remember correctly is adjusted with a feeler gauge. I messed with mine and wound up having to take it to my mechanic that handles the stuff that I either can't do or don't have time for. He got onto me for messing with and told me you should never have to adjust it unless it has been removed for some reason or has been replaced. It was something else that was causing the low idle but I can not remember what it was, to long ago. When I was trying to adjust mine I found a tech write up for it and still could not get it just right. Like you said my mechanic told me if I ever had to, for some good reason, you can get it close enough by doing it the same way you would adjust timing by ear. With it barely lose enough to move, turn it while the engine is idling until the idle is right and then tighten it back down, and that will usually get you there. Is what I found was that the adjustment is so sensitive that it can change when you re tighten the screws, that's why you want it barely loose enough to move, and leave it running while re tightening them so you can hear if it moves. And if I recall, there is no need to reset the ECM. The screws are beach to get too on the 91 4runner. Good luck.

toyinhawaii

yea ur right..on the 3.0..actually i have a 93 3vze xcab 4 x4 ..i picked up this 03 taco a month ago for 5k (blown head gasket)..the guy didnt even wanna bother with it even if he could fix it...he jus couldnt seem to trust it being fixed..his wife drove it and bought her a new car..he didnt want to worry.....i had a whole lotta experience on my 93 as well...on the throttle body, u could adjust the idle screw to get it perfect after fiddleing with feeler guage and everything else the taco doesnt have the idle screw,i also got the 93 at a good deal (burnt ex. valves)..sso went ahead and rebuilt the heads along with a few other things.oh by the way i got it up for sale on craigslist....craigslist>hawaii>under cars and trucks by owner>type in 1993 toyota truck..its the black 4x4 with my cell# 227-6933..i priced it a lil steep( you can always come down right??)..plus i think i really dont wanna sell it but cant keep both..hahaha...i still have my elky in the garage needin some tlc...but check out the prices toys are going for here....crazy!!!..back on subject..i think i'm gonna try to do the :ENG. WARM,NEUTRAL, AND THE connect terminals TC and CG of the DLC3...AND THEN ADJUST IT..and see if that works..like i said..i've always just adjusted it in park at idle....

***funny note..when i was buying the 03 off the guy..checking out the engine i wasnt familar w/the 3.4 but seemed very close to the 3.0..so anyway when i got home after about a minute i realized...no distributor..WTF!!!! and then following the plug wires..double WTF..only 3 of those on my V6 (gotta love that advancement of motoring technology..hahahaha)

Kiroshu

ok um....... who told you to adjust the tps? Your 03 tacoma prolly had no prob with it at all or it would have threw a code for sure..... so what you need to do is get your engine warm and at base timing and adjust idle using the idle screw.... and before you did all this do you check for vac leaks?

toyinhawaii

hey Kiroshu..funny..i was just posting a reply and the edited it with the funny note and bam u replyed with the idle screw..yea thats the first thing i did was check for leaks...but i am not aware of the idle screw on my 03..for now i'll check the fsm online again ,..then when i get home i'll lift the hood and give it a good look see...actually i was down to the tsp because that was the only thing left i could think of to bump up the idle...thanks

Kiroshu

hmm..... like i said before check for vac leaks.... i can't remember much about the 3.4s throttle body right now but check for screw. if there is one you have to set base timing to adjsut idle and once you set timing and adjust idle to proper speed then there you go.

toyinhawaii

yea..those vacumn leaks can be a problem..no matter how many times u know there could a leak..ur sure u checked them good..only to find out that one had that pin hole or that really fine hairline crack..whats crazy is my 93 has a ton of vacumn lines..i found a few that needed replacing, but the 03 has like a half hand full..easy to check..thanks..i'll be a triple checkin them though again

86-91-4runners

Yea, I have a 91 runner with the 3.0 and recently picked up a 96 runner with the 3.4 and wow my same reaction WTF almost no vacum lines etc etc. but that is way cool. With so few vacum lines on the 3.4 I would just say replace them all, just get several feet of new hose and remove and replace one at a time on the 3.4 that should be all of about ten minutes and a couple of bucks. When I replaced all of them on the 91 it was like several yards of hose and the good part of a day, a few were real hard to get to. I will soon be replacing all of them on the 96 even though it runs in top order I did find one that was split about an inch and a half up from one end, so that tells me do em all.
Happy Yota trails!

eddieleephd

My question is what plugs you are running?? The reason I ask is that I run a two step cooler plug and this is why mine idles at 750. I like it! But that is me.
The TPS in our trucks really are not adjustable because the ECM will find the starting out put and make that the 0mark then regulate from there which is why you can move while it is running and restart then it is the same as before. it could be the temp sensor it self not sending a proper temp reading. that would make it idle off at start and when it gets warm it clears up.

toyinhawaii

eddieleephd: MY PLUGS R THE TWIN ELECTRODE NGK..ACTUALLY I LOOKED AT THEM WHEN I HAD THE HEADS OFF AND CLEANED THEM..BUT NEVER TOOK NOTE ON THE #..ALSO 70% SURE THEIR NGK...ALWAYS SAW THE STICKER IN THE T.B COVER..WITH THE WARNING ABOUT USING ONLY TWIN ELECTRODE PLUGS..SO I'VE JUST ASSUMMED...ALSO THE REASON THE HEADS WERE OFF..IS THAT I HAD BOUGHT IT WITH A BLOWN HEAD GASKET AND NOTICED THAT WHEN I PULLED THE PLUG ON #5 CYL. (BLOWED HEAD GASK.CYL.) IT WAS CLEANER THAN THE REST..I KNEW WATER HAD GOTTEN TO IT..BUT CLEANED THEM ALL UP AND PUT THEM BACK IN..COULD THE GASKET LEAKING WATER INTO THE CYLINDER HAVE FOULD UP THE PLUG THOUGH????YEA, I DID NOTICE AFTER I CHANGED THE POSITION OF THE TPS,THAT THE TIMING MARK WAS STILL 10 DEGREES..I NOTICED AFTER I MOVED THE TPS FROM ITS ORIGINAL SETTING (THIS IS WERE IT WAS SET BEFORE I STARTED JACKING WITH IT)..UPON INITIAL START UP IT WOULD IDLE AROUND 1800 RPM THEN WITH IN A MINUTE IDLE DOWN TO AROUND 700 -+50 RPM, I SAW THE FSM'S TESTING PROCEDURE FOR THE ECT SENSOR...BOY..THATS A CHORE....I'LL DOULBLE CHECK THOSE PLUGS WHEN I GET HOME THOUGH..MAKE SURE THEY R THE CORRECT NUMBERED NGK

mjwalfredo

Ummm... Godzilla is right. There is no adjustment required on the TPS for 3.4. The computer controls the idle. Cleaning the IAC will help if the low idle is caused by the IAC but 650 rpm is fine. I have never heard of the control motor version....

Godzilla

The control motor version is the drive by wire system...i think the IAC is then an ISC?

toyinhawaii

mjwalfredo: yea i'm begining to think it may be that 1 plug could be fowled with the water getting to it..thats screwing me up..you're right, the truck is run by the ecm and all that is associated with the idle is fine/is in specs..but the iac i was referring to that i dont have..here..check the fsm
out: http://www.ncttora.com/fsm/2003/index.html and then go to fs-fuel system (5vzfe)...iac w/o etcs.......and then theres the one w/etcs (mine)..i guess toyota during mid year replaced the iac cause of this problem with the throttle control motor???