Check Engine Light / Highlander

[sitiakab]

The "check engine" light has been coming on in our 2002 Highlander (6 cyl - 4wd) with 60,000 miles. I twice tried the old trick of disconnecting battery to cancel in case it was a "one time" glitch... but it came back on again both times within a day or two. I know that I can pay someone to hook it up to an engine analyzer to read the codes. I was just curious if anyone else has had this problem with their Highlander (check engine light comes on) and what the defective part was?

[Hokie76]

The CEL came on in our 2003 Highlander (4 cyl; 6,000 miles) during the return portion of a 5-hour Interstate round-trip. The car continued to run fine. The dealer kept it for four days, saying the computer had displayed six trouble codes--all dealing with the emissions system--which took a long time to investigate. After all that time, they wound up simply adjusting the mixture, saying it was running lean.

The car ran fine around town for a month, but the CEL came on again during a repeat of the first Interstate trip. However, this time, the car seemed like it was "missing" for a couple of miles before we arrived at our destination, then it smoothed out. It ran fine around town. The CEL came on after we had gotten on the Interstate to head home. The car ran fine all the way home. The CEL remained on when the car was started several times over the next couple of days.

We are taking it to the dealer tomorrow, hoping they will not need another four days to figure things out.

[sitiakab]

Originally Posted by Hokie76

The CEL came on in our 2003 Highlander (4 cyl; 6,000 miles) during the return portion of a 5-hour Interstate round-trip. The car continued to run fine. The dealer kept it for four days, saying the computer had displayed six trouble codes--all dealing with the emissions system--which took a long time to investigate. After all that time, they wound up simply adjusting the mixture, saying it was running lean.

The car ran fine around town for a month, but the CEL came on again during a repeat of the first Interstate trip. However, this time, the car seemed like it was "missing" for a couple of miles before we arrived at our destination, then it smoothed out. It ran fine around town. The CEL came on after we had gotten on the Interstate to head home. The car ran fine all the way home. The CEL remained on when the car was started several times over the next couple of days.

We are taking it to the dealer tomorrow, hoping they will not need another four days to figure things out.

Thanks much for the info. You have an advantage over me as your vehicle is still under warranty, and while I know it must be frustrating to have to take it back in again, I am assuming you are not out any $$$.

I have disconnected my battery a few other times, and then reconnected to re-set the computer. The "check engine" light stays off for 3-5 days, 20-200 miles, and then it comes back on. I tried dumping some good fuel injector cleaner in it, but that did not help either. I guess sooner or later I will take it to the dealer, and they will probably end up "guessing" like the story related above.

[Hokie76]

Fortunately, we're not out any $$ -- just have to put up with the hassle of being without a car. We dropped the car off at the dealer last night and are awaiting word on what trouble codes pop out this time. The owner's manual says even a loose gas cap can light up the CEL.

Up until now, we were sold on Toyota reliability. My wife drives only about 6,000 miles a year, and it's frustrating to have this problem on a car so new. Now that the same problem has reappeared, we're checking into Florida's Lemon Law just to be prepared.

Good luck with your repairs. Hopefully, it's something simple and inexpensive, like a sensor.

[harryyf]

This is a moderate problem to Toyota cars. It comes from Mass Air Flow Sensor. You can clean it or replace it. If interested, visit this info at http://autos.msn.com/research/vip/Re...d=9450&src=vip or
http://www.autoshop101.com/forms/h34.pdf

[Hokie76]

Originally Posted by harryyf

This is a moderate problem to Toyota cars. It comes from Mass Air Flow Sensor. You can clean it or replace it. If interested, visit this info at http://autos.msn.com/research/vip/Re...d=9450&src=vip or
http://www.autoshop101.com/forms/h34.pdf

Thanks. The dealer reported last night that they're still performing "diagnostics." They said that the computer spit out the same six trouble codes as it did back in March, with the addition of a few new ones. I'll ask them specifically about the MAF sensor. The dealer will have had the car four days tomorrow, so we're concerned that they can't seem to figure out what's going on.

[ToyotaTech]

why is the first thing people talk about is lemon law? please get real. U have a light that is on that tells u something about your evap system Maybe u set the light yourself when u filled up your tank, Did U top off the tank? If u do did u know all u are doing is killing your car and wasting fuel? make sure that u make that gas cap click or the light will come on! please give us a break on the lemon law thing.

[RA64]

Originally Posted by harryyf

This is a moderate problem to Toyota cars. It comes from Mass Air Flow Sensor. You can clean it or replace it. If interested, visit this info at http://autos.msn.com/research/vip/Re...d=9450&src=vip or
http://www.autoshop101.com/forms/h34.pdf

thanks for that info, has anyone had this problem with a corolla (1zz engine)? i took my sisters 2001 corolla to the dealer,they said the filter was dirty and mass air flow sensor needed to be replaced. they wanted a load of money for the repair so i didn't do it, but I did replace the air filter. the engine runs fine but i notice some slight pinging/ticking sometimes under acceration. well any damage be done if i don't replace the maf sensor, and is there a way to clean it out myself? thanks...

[aoluser1]

The check engine light came on last night in my 2000 Toyota Avalon.

Many thanks to everyone for contributing so that this morning I tried the following steps:

1. Tighten the fuel cap. The label on my fuel cap indicates that I should tighten the fuel cap until it clicks otherwise the malfunction indicator lamp may come on.
2. Clean the Mass Air Flow (MAF) sensor (and let dry thoroughly) with cleaner for auto electrical parts.
3. Disconnect and reconnect the battery to reset the light.

I don't know whether it was the loosen fuel cap or the MAF sensor causing the check engine light to come on. But it was easy for me to do both step 1 and step 2 above. If you know how to locate the EFI fuse, you don't need to disconnect/reconnect the battery like me to reset in step 3.

I would like to mention one possible factor. A couple of weeks ago, after I took the Avalon to get an oil change, I noticed a burning smell. It turned out that some motor oil was spilled on the magnifold, creating an oily smoke (some of which might end up on the MAF sesnor).

The following link, though not for the Avalon specifically, gave me an idea of how to clean the Mass Air Flow sensor:

http://www.4x4wire.com/toyota/mainte...tenancep5.html

Good luck () and make sure you are familiar with the necessary safety precautions before making your personal attempt.

[joey#1]

The Highlander is one of several Toyota models covered under the engine sludge program. It covers models from 1997 - 2002 and is for 8 years from the original purchase date and is for unlimited miles. One of the signs of sludge is the CEL. Other signs that you may or may not have in addition to the CEL are a very high use of oil, smoke coming out the exhaust, and sometimes you can actually see the black goo on the dipstick. Toyota has held that the problem is from lack of owner maintenance, but did some design modifications immediately upon announcment of the program in 2002 to reduce sludge chances. If you want more information on this, go to http://www.autosafety.org. They have a copy of the letter that Toyota says they sent to all 3.3 million owners of the affected models and also copies of the news articles that explain the program. From what I have heard, Toyota will want proof of reasonable maintenance before they will do the fix (the fix costs over $4,000 if you are not covered under the special program).

In addition to the sludge problem, there have been some emission related problems with Toyota that could also trigger the CEL. Another good source of information that includes the emissions as well as sludge info is http://autos.msn.com. You can use the pull down menu at the top left for Used Highlander and whatever year you are interested in. Then go to the tab for Ratings and Reliability. All of the sludge generation Toyotas are listed as having +++significant+++ engine problems both due to sludge and emission parts.

[sitiakab]

Well - I should have updated this weeks ago - I finally gave up and took it to the dealer and the codes showed a vacuum leak. I thought, that's unusual for a newer car... and then thought about how could a hose become loose or damaged. I recalled that there were a number of hoses connected to or running around the air cleaner box.... and I do all of my own regular maintenacne... and I recalled always having a tough time getting the air filter box lid cover back on due to the hoses.

I suggested the dealer look at those hoses first... and sure enough... one of them was broken and leaking, probably something I did when changing an air filter. They replaced the hose - and no more "Check Engine Light".

Moral of the story... sometimes when you try and save a few bucks and do your own work, you break something else that costs you even more money... in this case the hose was just a few bucks... but the labor to run the tests and install a new hose was $75

[pruebel]

Boy, that was easy. The web site on the cleaning the MAF and resetting the fuse worked perfect!

Originally Posted by aoluser1

The check engine light came on last night in my 2000 Toyota Avalon.

Many thanks to everyone for contributing so that this morning I tried the following steps:

1. Tighten the fuel cap. The label on my fuel cap indicates that I should tighten the fuel cap until it clicks otherwise the malfunction indicator lamp may come on.
2. Clean the Mass Air Flow (MAF) sensor (and let dry thoroughly) with cleaner for auto electrical parts.
3. Disconnect and reconnect the battery to reset the light.

I don't know whether it was the loosen fuel cap or the MAF sensor causing the check engine light to come on. But it was easy for me to do both step 1 and step 2 above. If you know how to locate the EFI fuse, you don't need to disconnect/reconnect the battery like me to reset in step 3.

I would like to mention one possible factor. A couple of weeks ago, after I took the Avalon to get an oil change, I noticed a burning smell. It turned out that some motor oil was spilled on the magnifold, creating an oily smoke (some of which might end up on the MAF sesnor).

The following link, though not for the Avalon specifically, gave me an idea of how to clean the Mass Air Flow sensor:

http://www.4x4wire.com/toyota/mainte...tenancep5.html

Good luck () and make sure you are familiar with the necessary safety precautions before making your personal attempt.

[avklevens]

Mass Airflow Sensor cleaning and reset of the EFI worked like a charm for me on my 2001 Highlander.

[dbeals]

Check engine light came on my 2002 Highlander at 45K miles. Turned out, one of the hoses connected to the air cleaner box was disconnected by one of those quickie oil change establisments when they removed the air filter to show me its condition. The Toyota dealer was able to diagnose it immediately, fixed it, and cleared the code.

[JJ_Mclure]

my check engine light came on and also my VSC light.
took to dealer and they replaced the Overflow Vent valve, Charcoal cannister assembly. it was under warrenty so I didnt pay. car had 5700 mi on it. 2004 highlander