High, Unstable Idle on my new 2.7L (SOLVED)

Just got a 2001 xtracab 2.7l 5speed with almost 150k miles on it last week. Test drove it and the idle was good. I don't think the previous owner drove it very much for a while. After the 2 hour freeway drive home, something must have broke and I noticed the idle was too high, around 1500rpm. Idle has been bad since.

When starting, the idle is way too low, surges, shakes the truck, and almost stalls. After maybe 15 seconds of starting, the idle will shoot up to ~1500, but will be very unstable and slowly change from anywhere in between 700 - 1600. The idle is never stable, even when fully warmed up.

No check engine lights. Evaporative system is incomplete. It did have a p0402 code (egr flow excessive), but I fixed this with a new VSV for the EGR. I cleared the code and it hasn't come back.

MAF sensor is clean, throttle body I cleaned (already was pretty clean), new spark plugs (old ones looked good).

I'm going to take the truck to a Toyota dealer to get a recall done soon(front lower ball joints), so I figured I would have them diagnose the idle problem too, but I wanted to ask this forum for anything I should check or fix before I pay them to diagnose it. Thanks.

 

Sounds like a possible vacuum leak, another cause could be a sticking idle air control valve.

 

i know the code is different but when my tps was going out it acted the same way.

 

[QUOTE="slime-taco, post: 24953216, member:

I'm going to take the truck to a Toyota dealer to get a recall done soon(front lower ball joints), so I figured I would have them diagnose the idle problem too, but I wanted to ask this forum for anything I should check or fix before I pay them to diagnose it. Thanks.[/QUOTE]

Can't help you with the idle problem, but what is the recall you mention for the lower balljionts?
I wasnt aware that there was an active recall on them. Did you get a letter from toyota ?
Thanks

 

I thought it might be a vacuum leak too, but I cant find any. Going to inspect and clean the IAC when I get the gasket for it in a few days. I don't think it's the TPS because I checked it with an obd scanner and it seems to be acting right.

Cucvfan, I saw there was a recall when I put the truck onto my carfax account. The recall was issued in 2005 and says; During the manufacturing process, there is a possibility that the surface of the ball portion of the Front Suspension Ball Joint in your vehicle may have been scratched. - so, free new front ball joints!

 

I’m not sure if that recall is still active, especially on an ‘01 but if it is, damn you’re lucky cause lower ball joints are pretty pricey

 

Took off the throttle body today and found that it has a new IAC valve that isn't OEM... No branding on it other than 6647e15. Tested it with a multimeter and got results way off from what they should have been according to the manual. One of the screws on the valve was totally rounded so I didn't take it off to clean/further test, decided I'd wait to cut it until I get a new OEM valve and screw. That was until I saw these things are $200 from Toyota. So, I'm ordering a cheepo valve on Amazon for $40 and hope it will temporarily fix the annoying idle, until I get the cash for an all new $400 throttle body with everything on it.

And yeah the recall is still active, getting it done in a few days when the parts get in. They want $170 to diagnose the idle though, F that!

 

Fixed!
I got a new throttle body with iacv and tps from Toyota for $400. Put it on and started it and fixed! Sooo much better.

The reason I put 'kinda' in the title is because I don't know what exactly was wrong with it. Took off the IAC and it was totally clean and there is very little wear on throttle body. I bet it was just the IAC though, since it had some weird aftermarket one that tested totally wrong with a multimeter. OEM IACV from my dealer is $300 though, so why not just drop another $100 for fresh throttle body.

Hope anyone else having this problem gets it fixed easily!

 

@slime-taco Do you have carfax account? Heard those account can cost hundreds per month. If so...BALLER.

 

haha the account is free but i did pay like $40 i think to check the vin on there, which is totally worth it when getting a used car.

 

Glad you ended up solving the issue! I'd put good money on the iac being the culprit. I would also hold on to or sell that throttle body, i'm sure that its worth a pretty penny even with the issue.

 

I took off the IAC and it was definitely the problem. Tested it with 12v leads and nothing happened. I think the previous owner of this truck was a flipper and tried to fix this problem as cheaply as possible before selling it. The cheepo aftermarket IACV looked new with no carbon build up at all, and its gasket was for a completely different car. The gasket wasn't even close to fitting at all. Probably will end up selling the throttle body because even after 150k it doesn't seem to have any wear.

But I'm a really happy owner of this truck now, it runs very smooth and I think it was a great purchase. Plan to keep this thing for life.