check engine light question(s)

[TRD_1320]

My '00 Tundra check engine light came on about a year ago. I also noticed the V8 was missing at idle speed. I wish I'd known about the Autozone policy (I would have saved $20 for a local mech to hook up his OBDII reader). Code was unrelated to gas cap or filler neck. It had to do with the ' Idle Control Motor '. We turned on and off the AC, and move the steering wheel to the right and left, both of these tests resulted in an idle RPM increase, indicating that the Idle Control Motor seemed to be functioning normally. The idle RPM range was suspect though as it was as low as 300 rpm at times.

The entrance to the plenum has a butterfly valve that is controlled by servo motor. The gap around the butterfly/plenum bore was partially blocked by a sooty deposit. A can of 'injector safe' cleaner and a clean rag worked the sooty material out of the area. The mech cleared the code, and my idle problem went away.

...as mentioned above, the check engine light can be triggered by a number of problems. I think you should visit your local Autozone and find out which code your dealing with before you go and refinance your home to pay for the repairs on your Tundy... ;-)

JMH

[tconnors]

Yeah, they replaced my O2 sensors after 2 years, and now again after 4 years (yesterday), and my check light went back on ater 20 miles. Repairs under warrantee, but I'd be happy to pay if they fix it right the first time!

[MyTundra]

My CEL came on twice in the past three years and each time it was the O2 sensor which needed to be replaced in both instances. Luckily, both were under warranty, and the second instance they had to replace the exhaust manifold because the failed sensor fused in-place.

[Bench]

Originally Posted by oshp6179

Having the experience that I just had with my light, I try to keep my tank at least half full all the time, and that way I can justify pulling into a gas station whenever I see a decent price. That seemed to play a part in the light coming on, at least when it got below a quarter tank. However, that idea was nixed by the techs that said some of the internal tests run by the computer do not activate unless you've been driving for a certain period of time.

I realize this is an old thread, but I thought I'd chime in case someone else is wondering about this. I think you're on to something here: First I should probably add, that I came to this same conclusion before reading your post. We have a 03 Sienna and until 3 months ago we never let it go below half tank. The first or second time we did (about 1/4 tank), the check engine light went on. Took it the dealer and they gave me the old "loose gas cap" code story. I started keeping track of gas levels and about 1/4 tank the light goes on again.

I reset the EFI fuse each time and kept track. It may not happen the first time you go below 1/4 tank, but it'll happen the 2nd or third time (but only after keeping the tank above 1/2 for a period of time. I'm no mechanic, but from what I've been told and read about here about how the system resets itself, my guess is the computer keeps an average on its sensors (probably tank pressure in this case), and once it finds something outside the realm of "normal" for its average, it sets off the light.

I think this is right because while testing gas refill levels and I consistently go below 1/4 tank, the light won't go on. So there it is. Right or wrong, I hope maybe someone might find this useful.

Ben

[sydgrant1]

Seems to be a problem w/these Tundras. I was driving down a dirt road yesterday in my '02 Tundra ( w/ 44K miles ) and the "yellow" engine light came on. In my past experience w/cars they will go off and come back on when you restart. Two days later it still burns bright.

Haven't tried the gas cap but also curious if this could have jarred teh O2 sensor loose.

Anyone else had this happen. Luckily I purchased the extended warranty to 65K miles.

[30yrsoftoy]

I know this is an old thread,
I have had my check engine light on since i had 40,000 miles, I now have 100000 miles. I just use it in small town setting for what a truck is used for. I had it checked with family mechanic a few years back, who works for a dealership and he said just to put a piece of black tape over it. Never had a drop in gas mileage and never really had to do anything more than regular maintenance. (what a good toy is supposed to be like). I'm convinced it is something the automotive industry does to make money off. (parts and service...etc) I don't like having someone I don't know work on my car because of shady practices in my experience.