high idle 2001

Having a high idle issue thats driving me crazy!!! Need help open to any suggestions... 2001 toy v-6 3.4 4x4 manual w/ trd. So I have replaced the maf, tps, iac, spark plugs, wires, vacume lines, 02 sensor. I recently even got a used throttle body from a newer wrecked toyota. Currently my idle is at 2-3k depending on what I'm doing. Driving in town it will idle at 3.1k when at a stop light. At my house if I let it idle for a while in the driveway it will go down to 1800. Willing to provide any info to anyone who would give me the time, much appreciated in advance...

 

Maybe check if the floor is cracked around where the throttle cable goes through.

Are you getting the PO505 code at all ??

You checked for vacuum leaks allowing unmetered air.

Throttle cable frayed in the cover causing it to hang up.

 

thanks for the reply, no havent checked the throttle cable, but there is slack in the line at the linkage. yes I actually just replaced all the hoses, bought a couple of different sizes of the hose and replaced all the vacume lines.

 

not getting that code, however I'm getting a code for my catyletic converter, but I dont see how that could cause a high idle?

 

You do lube the throttle body linkage now and then?

 

honestly I never did, but I have several times recently. I can physically push the throttle closed all the way and I'm still at 1800.

 

Suddenly my 1200rpm idle doesn't seem so bad... Still following for ideas, sorry I'm no help.

 

Just how did this start ?? Do any work to the engine area??

Vacuum hose installed wrong ??

You checked the entire Air intake system it sure seems your getting unmetered air.

Throttle body gasket sucking air bore of throttle body egg shaped allowing extra air

If it is not mechanical your getting extra air

A bad Coolant temp sensor should not cause rpm as high 3000 rpm thinking the engine is cold all the time.

 

Been out sick for the last few days, nasty flu......
So this all started about 3 months ago. I drove into town which is about 24 miles oneway, the truck had been running good previously with no issues. I stopped at a grocery store, when I came back out and started my truck there was something immediately wrong. It was running super rough, bad idle, starving for power. My check engine light had been on previously due to a bad c02 sensor that I had been ignoring. Once leaving town and getting on the interstate to return home the check engine light started flashing/blinking on and off and the truck was running like crap. The next day I started the "rounds" of different places to get the check engine light checked out at, O'Reileys, Napa, Auto Zone, ect. I now call the check engine light, CHECK YOUR WALLET. I would rotate the different stores trying to get different info and advice. The first code was a misfire code for cylinders 3 and 4, so I got new spark plugs and wires, then ended up getting new coils. At this point still running rough I read online on this forum about cleaning the throttle body, had never done that, my truck has 205,000, upon doing that I noticed on the inside of the throttle body wall a gouge or a dent if you will where the butterfly choke meets the aluminum wall towards the back of the engine or closest to the cab when in place. So up until cleaning the throttle body my truck had only been running rough, missing/poor idle, i'd really step on it when taking off and it would sputter and the check your wallet light would start flashing. Once I cleaned the throttle body and put it back together it ran amazing, except for the high idle. It was idling at about 1800 pretty constant except when driving at higher speeds and pushing in the clutch to downshift out of 5th my rpm gauge would drop all the way down to 750 where it should be then back up to 1800 and it would just go between those two numbers until I shifted or slowed down to a dead stop then it would always go back to 1800. I also forgot to mention that I changed my fuel filter at the time that I cleaned the throttle body. So at this point I was still getting the check your wallet light and this is when I went on a frenzy of auto stores replacing everything with brand new parts. I replaced maf sensor, IAC, TPS, I also ran two bottles of seafoam and eventually a bottle of stuff to clean out the catyletic converter, another check your wallet solution from AutoZone. All of this time I'd been researching and asking around what could be the issue. I also found on this forrum the "washer trick" which did help a little, brought it down to 1500 instead of 1800. It took me a few times of taking it apart and putting it back together in order to get the right size washer to get the gap to the right size. So in this process I actually stripped the bolt that the linkage goes on. So started the next phase of finding another throttle body, really didnt want to buy a new one, like 750$ new. Took me about a month to find a used one, after getting one off the net that didnt work. I was convinced that the "new" throttle body was going to solve my issue, thinking that the dent or gouge on the old one was what was causing the high idle. Upon getting the new/used throttle body, from a wrecked truck with 160,000 I immediately noticed that it had an almost identical dent or gouge in the same place, maybe not quite as significant but it was still there, atleast the bolt wasn't stripped. So in putting this new throttle body on thats when I got an even higher rpm, thinking maybe one of the components was bad, IAC or TPS so I replaced them with the new ones that where on the old throttle body. Absolutely nothing changed. So right now when I first start it it will start out at about 1200 then as the engine warms it will go up to 1800, when I start driving down the road and push in the clutch it will be running at 3100, if I rev the engine to redline with the clutch depressed rolling down the road the rpms will go to 750 then right back up to 1800 and stay there until I let the clutch back out and continue down the road, then back to 3100. I had replaced all the vacuum hoses with new rubber correct sizes, and the gasket for the throttle body is brand new, second one. Somewhere in this frustrating process I also replaced bank one c02 sensor, brand new. All in all I'm in this truck over $1500.00 in new and used parts not to mention the amount of time and frustration. I am a fairly mechanical sound guy, I have always done the maintenance on my rigs, and besides this I have never had any other issue with this truck. I am convinced that its computer related, it totally has the ability to operate/idle at 700-750 where it should be but something won't let it. I've tried disconnecting the battery to "reset" the computer, i've pulled fuses, i've check wires, I'VE GOT NOTHING! I heard in this journey from a guy that a toyota dealership is the only place that has some type of a computer that needs to "reset" the computer in order when you ever put any new electrical component on your engine??? Could this be? Not from the countless threads that I've read! Would love to get any advice from anyone who thinks they have a solution to this madness! Sorry for writing a book but I wanted to include everything. Thanks so much for your time and energy into this debacle!

 

I've just encountered the same thing all the sudden. I simply cleaned my MAF sensor and now I have the same 1800rpm idle issue? Trying to find answers but I'm not having much luck either. My 0171 code is gone though?

 

https://www.tacomaworld.com/threads/throttle-body-re-bore-high-idle.645688/
https://www.tacomaworld.com/threads...le-body-butterfly-repaired-by-maxbore.479914/

 

If you really think it's computer related. Try replacing the ECU "the computer"

There's good ones on ebay for like $95 wouldn't hurt to try and see if they work, and then return them if they result in the same issue.

 

Also, where did you buy your O2 sensor? I bought a fake one off of ebay a while back and was experiencing similar problems like yours. Except mines would have random fluctuations with high rpms while idling. The fake O2 sensor also gave me fake codes that I didn't have before installing it.

 

given that the rest of the motor is mechanically sound and you have no false air, the throttle body is worn out...

 

Did this problem ever get fixed? I’m having the same exact symptoms on my 99 3.4.
Hoping to bring this thread back