Toyota Tacoma Engine Light

I tried taking off the gas cap, heard the whoosh, put it back on, but the CEL did not clear. I did this twice. It is about 1/4 tank. Don’t know if it’s 1 or 2 issues.

I brought this to their attention on the work order but they found a new problem…

thank you it took 10 responses ,BECAUSE NOBODY READS THE REPLIES,they just throw out some useless info based on the OP.

come on fellows read the WHOLE response. and replies.

I was waiting for someone to figure it out. NOW JUST IMAGINE YOU WROTE THE POST,and had all this HUB BUB.

your killin ME! lmao!

METOO2?
I don’t think that Donna understands you. Would you explain it to her in layman’s terms? I think she will understand your point, then.

like to ! but you know thats not possible!

thats a computer telling you it SAW a PROBLEM and its for REAL.

O2s will not fix anything (for this problem)NOR will the clutch fan.

find a new tech,not a MECHANIC.

ask for the TRAINED GUY AT THE DEALER,NOT the person whos next in line.

GOOD LUCK.

thanks- if the clutch fan does not fix it i am done fixing it. from my side of the counter i am hearing ‘we’ve got our best guys on it’ from toyota themselves in california they said ‘it COULD be bad gas’ so it is my bad luck to be dealing with a toyota-GM issue with all the politics going on now- but the dealer’s bad luck he sold me a lemon- & if there are no good techs at all 3 dealers that is their bad luck, too.

maybe this is the answer… i found it on another post from ‘old school’

Oxygen sensors can be checked with either a voltmeter,a scan tool or a lab scope.

The best tool is the lab scope,you can compare the waveform with examples of what it should look like.

With a voltmeter you look for a cycling voltage signal,but the readings are harder to interput than looking at a waveform on a lab scope.

All this info is in your basic engine performance chapters of your textbooks.

Air/fuel (wide band) sensors don’t have waveforms, nor cycling voltage signals. These are some of the differences of traditional narrow band oxygen sensors, and air/fuel “wide band” sensors. The engine computer looks at the current, from the A/F sensor, to determine the air to fuel ratio. Voltage is constant.

What the Toyota “wide band” oxygen sensor is, and how it’s different from a regular “narrow band” oxygen sensor: http://en.wikipedia.org/wiki/AFR_sensor

new symptom… the CEL did NOT go off when I re-fueled this afternoon…

You have the truck back and you’ve refueled it! There’s a big gap. What did they do, and what did they tell you? Clarify. Did the CEL illuminate, or not? Did you take the truck to an auto parts store and have it scanned? If yes, what codes?

Same as last week- I took it to another Toyota dealership (Friday) for a second opinion and their diagnosis is “Coolant fan clutch coupling not releasing causing coolant temp to stay low, recommend replacing.” She said something about it overheating, which sounds bad. Some notes on the work order are more specific “Coolant temp not reaching 210 degrees” so she is going to “order the part and call me when it comes it” The Chevrolet dealer is paying for the parts and labor (supposedly) although the last time he said that he stuck me with a bill in my name.

So, just a brief update, I took the truck back last Thursday (12/11) and they replaced the coolant clutch fan coupling and it is fixed, I think. We took a road trip from Boston-Philadelphia this weekend and the light stayed off even though we re-fueled 3 times and got stuck in a good bit of traffic along the way. Hopefully, this is it!

Well, GOOD. Maybe, they did find the true cause. I think that the mechanics missed it because they hop-scotched around in their troubleshooting…mixed with repair-by-symptom parts replacement. A lot of the “thinking” is done for the mechanics when they hook up the factory scan computer and start somewhere in the diagnostic menu. Then, it’s just a matter of pushing menu buttons. I think that if they had just started at the beginning, and gone through every step, they would have found it much sooner. Machines can’t replace thinking.
As Mr. Spock says, “Drive well, and perspire”.

I sincerely hope and trust that the problem is fixed. Sounds like they ultimately did their job right and my guesses were incorrect.

Apologies for disappearing. I was victim to the massive record breaking ice storm up here in NH. I had to relocate to a hotel. As I write this there are still areas in NE without power.

Unfortunately, the CEL came back on Christmas morning when the tank was half empty. It’s been off for 2 weeks since the last fix at Toyota and this is very discouraging.

The exact part number for the oxygen sensors is critical. A Toyota dealer can look up YOUR VIN, and find the exact part number needed. We have had postings here where people suggest going to AutoZone or online parts, and ordering this or that part. Don’t do it. Get the right part and the only way to be sure is to have your VIN looked up in the Toyota database.

You didn’t see the light for 9 days; then, Christmas Day, it’s back! What a Christmas present!
It’s time to go to an auto parts store for a scan for DTC (Diagnostic Trouble Codes). Out of the hundreds of signals, which could turn the check engine light on, why limit yourself to just one possibility?

P0420- from Autozone (the same code that’s been on for 3 months)

Thanks for all the replies. I am giving up on the truck and pursuing legally binding arbitration with the dealer under the lemon law via the state attorney general’s office. Never had this kind of thing happen to me but that’s what the law is for.

This is an old thread but I cannot figure out how to start a new one. I have a 2017 Toyota Tacoma and the engine light started coming on at 12,000 miles. it is now at 18 thousand miles, 2 years and 10 days old. It would come on when the gas tank was half-full or less and when I filled the tank it would go off and I would drive it a week or so and then it would come back on when the gas tank and drop below half. I rushed it to the Toyota dealership the first time it came on and they stuck the thing on it and told me that they did not know what was wrong with it and they turned it off and said let him know if it came back on again. There were 4 codes, all evaporative. But it came back on again so I took it to the Plaza Tire Place and they struck the little thingy on it and said it was 4 codes, all evaporative or in that area and they turned it off and said take it to Toyota because it still under warranty when it comes back on. So the next time it came back on I called Toyota and said I want it fixed. I’m paying a lot of money for this truck and it’s under warranty. And the guy yelled at me and said he didn’t know what was wrong with it and then he said he would have to leave it for a few days I said that was fine they just needed to give me a rental. And then he yelled at me some more he said I was yelling at him but I was not. I was using my strict I am a school teacher and you did not do your homework voice. Most definitely not yelling. It did not come on at all during the summer but it just came on yesterday which I suspect has to do with it turning cold. ( the first time it came on was exactly 1 year and 1 day ago) I’m taking it to the Toyota place now and I want it fixed. Anybody want to give me some suggestions of how to make them cover this under warranty. I’m really upset because it’s a two-hour round-trip and I buy a brand new vehicle so I don’t have to do this.