2001 tacoma high idle

We have just bought this truck for my son, 01 tacoma with 2.7. It cranks fine and it starts idling up, the warmer it gets the higher the idle. It tops out around 1800rpms and stays, even with the clutch pushed in or sitting in neutral. You can turn it off and crank it and it goes right back to high idle. I'm about to pull out what little hair I have left!!!!!

 

Is there a check engine light on?

 

Yes.

 

That will more than likely tell you what the issue is, you'll have to get the code pulled. Take it to AutoZone, O'Reillys, Pep Boys, etc. and have them hook up their scanner and read the code, they should do it for free. Once you have the code, post it up on here and let us know.

Otherwise it's just a guessing game, there are numerous issues that could account for a high idle but with the code we can narrow it way down.

 

By chance, did the previous owner mention if he cleaned the throttle body or MAF sensor?

 

My guess was going to be MAF sensor, and any issue with the MAF sensor will set the check engine light off. P0171 is usually the code thrown for that I believe (also the code for a vacuum leak which could also cause a high idle). But again there's no way of knowing for sure until the code is read.

 

The previous owner didn't clean the throttle body and they did put a k&n filer kit on it

 

K&N air filters are notorious for ruining MAF sensors by getting the air filter oil on it. My money is on the MAF sensor needs to be replaced, but you could try cleaning it first. It's really easy to do, make sure you buy MAF sensor cleaning fluid specifically (do NOT buy generic electronic sensor cleaner or carb cleaner), take off the MAF sensor and carefully spray the fluid on it according to the instructions on the canister. All you need to remove the MAF sensor is a screwdriver.

Still though, you should get that code pulled and post it up on here so we can know for sure what's really going on with your truck.

 

Take that K&N filter out and throw it in the trash, where it belongs.

 

The code is P0340 (camshaft position sensor).
I have already changed this 2 weeks ago and it's still throwing the same and only code.
I have the MAF sensor cleaner and going to try that just to narrow down the problem. What all do I need to replace the k&n filter that's there with the factory stuff?
Thanks for the help so far!

 

Is it just a drop in K&N air filter or is it a cold air intake setup? If it's drop in, head over to an auto parts store and tell them what kind of truck you have...they'll pull up the right part number for the air filter you need and will most likely have it in stock. I prefer Wix brand myself, they're like $20. Then you just pop the K&N one out and toss it, and pop the new one in.

If it's an entire cold air intake assembly, I think you'll have to source the stock air intake setup parts to replace it with but I'm not entirely sure.

That code for the camshaft position sensor is concerning, I've heard of those going out on Tacomas before and it renders them useless (until it gets replaced). Wonder why the code is still showing if you've already replaced it? That is more than likely what's causing the high idle as a symptom of that issue if it's still persisting. Did you have a shop do the work or did you do it yourself? Only asking because if it was a shop, then they should have some kind of warranty on their work and will likely look at it again for you if you take it back in.

 

No idea about the 4 cyl, but this sensor, on the 6 cyl, is under the timing belt cover (you have a timing chain) and is vulnerable to contamination from a bad water pump, cam shaft seal or front main. Locate it and see if you have a bad seal or bad/loose connection.

 

I replaced the camshaft sensor myself cause it's easily accessible just under the throttle body. Just picked up a new one cause it had a 1 year warranty on it, free of charge. The k&n kit is a whole kit and I will.need to replace with a new air box.
Going to replace the new camshaft sensor and see where that gets me..
Just spoke with the previous owner and he said it never idled high with him u til he had the cat converter taken off. It was not replaced.

 

Replaced cam shaft position sensor, cleaned MAF sensor, removed and cleaned throttle body(very dirty) and the only result I get is the rpms fluctuate from 1100 to 1800 constantly all vacum hoses are in good condition and hooked up. Where to next?!!!!!

 

Disconnected battery for about 20 minutes and hooked it back up, within 25 seconds it's idling constant at 1900 rpms, no fluctuation. Is there an end to this madness?
Really starting to wander if it has something to do with the emissions.

 

Replaced the TPS and cleaned the IAC valve, got it all back together and started it up. Started at 1000 rpms for 10 min then once it got warm, it crept up to 1900/2000 and stayed!!!!!!!
What's next any suggestions?

 

Probably a bad IAC valve or a vacuum leak. also low coolant can cause this.

 

I changed my bank 1 cat and had same problem 2k rpm no codes thou. no vaccume leaks. did you get any more leads?

 

I changed the IAC valve with a new one and it's been great. The most expensive part was the problem for me

 

Did you use Factory OEM 300$ IAC?