My 1997 Toyota Rav4

[Brian McVickers]

My 1997 Toyota Rav4

Hi,

I'm looking for help in diagnosing my check engine light.

History – A year ago it failed the AZ emissions test due to the check engine light being on.
We took it to a mechanic who for $3,000:
Replaced the Charcoal Canister
Replaced several of the lines/tubes within the evaporative emissions system
Replaced the EGR - ? Valve
And replaced any other hoses that looked deteriorated or cracked in the emissions system.

The check engine light went off, the vehicle passed emissions and we went on our merry way!

About a month later the CE light came back on for two weeks then turned off.
About three months after that the light came back on for a week then went off again.

A month ago the CE light came back on, I had the codes run and they indicate that the gas cap is loose...but that could also be an emissions system problem, the gas cap is just the most common.
A week later the light went off
We received our emissions check renewal letter
I am scheduled to take it into the testing station today

Yep you guessed it!-- I started the car this morning and the Check Engine light is on, so it will not pass.


Any ideas?

The vehicle runs fine
It is a 10 year old pokey 4 cylinder that could probably use some new spark plug wires but it runs just fine.

Thanks

 

[kcowyo]

02 sensor.

Take it to a Toyota dealership and have them replace it for $40 or flash it and it may clear. A loose gas cap will trip it, gotta make sure they're on snug. You can also unplug the battery for 30 seconds at it will clear but the light will come back until you replace the 02 sensor.

Pretty common problem. Just sent in the Mommy wagon, a '99 4Runner, with the same problem.

 

[Pskhaat]

First, take it to AutoZone and get the OBDII code red from it for free. It should identify the exact problem. Post back the results here. After that, unplug the battery for about 30 minutes, plug it back in and go get `emissions' tested. I'm guessing O2 sensors too.

On that note, you may actually opt to get a reai emissions test (should be same cost?), where you can see what kind of CO2, NOx, etc your engine is emitting.

 

[Pskhaat]

How many miles?

 

[Brian McVickers]

~ 108,000 miles

yeah, I am seeing myself parked a block away from the emissions test facility for 30 minutes with the battery disconnected. Reconnect and hope the line is short!

 

[paulj]

If the general Toyota knowledge here does not help, you might want to try a RAV4 forum, such as rav4world.com

 

[Brian McVickers]

Nice,
There's a web forum for everything!

 

[datrupr]

Brian, if it is reading the gas cap, it could be just that. The gasket inside the cap could be wearing and creating a good seal. Go to Checker or Auto Zone and see if you can't get a new one. Probably not more than $20. Then, while you are there, scan for codes, clear them and see if comes back on. If it doesn't then you probably fixed the problem, if it does you just spent $20 on something that you will probably need down the road anyway, and you wasted a little bit of your time. I don't think it would be an O2 sensor if it is intermittent like that. I could be way off though. I have the same problem with the Trooper, the CEL will come on and stay on for a period, and then occasionally it will go off. Go read the codes and it is saying that both of my banks on each side are running too lean. Sounds like an O2 sensor right? Nope, it is my Intake Manifold Gasket. I have know about it for about a year now, and eventually I will get the time to fix it. Good luck, man.

 

[jeffryscott]

In Tucson, at least, the gas cap is pressure tested, so if it is bad it would need to be replaced anyway. O2 sensors would also make some sense with that mileage.

Good luck,

Jeff

 

[robert]

And here's the answer you don't want to hear- it may be a short too. Electrical gremlins can be the devil to track down. Check all of the lead(s) to your sensors that you can find. If you have gotten dirt or mud in them that can cause probelms. You have two O2 sensors in your exhaust line; if you drive off road you may have knocked one loose or gotten junk in it (usually the rearmost). You can test them to see if they are still good using a multimeter but you have to find the reading somewhere. You may have inadvertantly damaged the fill gasket between the filler neck and the tank; it sometimes happens when there is a gasket there (I know almost nothing about the RAV4s). I do know that Bosch probes are expensive but that you can buy them yourself and put them in; I've also seen where folks have pulled, cleaned then reinstalled them.

There should be a button to reset the light so that you don't have to unhook the battery. On the older Tacos you popped out the switch panel cover to the right of the steering wheel and you could see it in there- push it in and you're good to go.

Course you could unplug the light from behind the dash too.

I hate emmisions testing (glad we don't have it here)- just another way to make more money off you, take cars off the road and generally be a PITA. With so few cars on the road past ten years these days it really should be a non-issue.

 

[Pskhaat]

Unfotunately, in AZ emissions areas, the system test is through OBDII so the computer will still report a CEL/MIL with the bulb disconnected

 

[Grim Reaper]

.

. You can also unplug the battery for 30 seconds at it will clear but the light will come back until you replace the 02 sensor.

.

Don't do this.

While resetting the computer was pretty much the standard you can't do this on OBDII emmisions that this vehicle will have. The ECM data logs failures and events and if that data log is empty from a reset it may fail you.

Also have you checked with Toyota for any TSB's on this type of problems?

It has a brain ask it what's wrong. The ECM is self diagnosing and before you spend another penny you need to ask it wats wrong.

$3k for that list of junk......MAN WHAT A RIP OFF! if you are prepared to spend that kind of money take it to the dealer. They will at least stand behind their work and you can hold corperate over their head if you are not happy with their work.

30 seconds with Google reveales this TSB
http://rav4world.com/tsb/EG003-98.pdf
That $3k mechainic should have looked this up.

Another possible thing to check
http://rav4world.com/tsb/EG003-96.pdf

This has some related information to EVAP systems.
http://rav4world.com/tsb/EG005-01.pdf

All this was found here.
http://rav4world.com/tsb/tsb.html
Seems to be a really good site with a lot of good information available.

Main forum. http://rav4world.com/

 

[Brian McVickers]

Yes 3K was a terrible rip off.
And no I was not prepared to spend it in any way!
Therefore I will not even mention the mechanic and shops name since some could consider any press to be good press even if it is negative press. The guy really turned out to be a condesending jerk who told me it was my fault for not taking better care of my vehicle. Ok yea sorry buddy, I forgot to investigate for age cracked hoses within my emmisions return system that are up under the fram during my last oil change! There is more but I get pissed off thinking about it so I'm done.

 

[Brian McVickers]

WE PASSED, WE PASSED:victory:
I took it over to Autozone, they cleared the codes and recommened I drive around and then come back for a fresh reading if the CE turns on again.

With clean codes and no CEL I drove, very gingerly, two blocks to the testing station and passed with flying colors!:rockon:



We shal see, if the light comes back on I'll figure it out.

Thanks for all the input!

 

[Hltoppr]

I second a bad gas cap or O2 sensors, pretty common maintenance item on Toyotas of that mileage.

Remember...CDan on IH8MUD for your OEM parts needs...don't even bother going anywhere else....all Toyotas deserve OEM parts!

-H-