Okay I am relatively new to 3rd gen runners, but the Check Eng light is on now for a couple days and I was wondering How dire is this situation or is it a Toyota Payday Hook
I was planning on waiting till next week to check it out..is there a rush???
Thanks in advance for your help.

-Bill

 

Mine came on last week and I just disconnected the battery for a half hour and it hasn't come back on...at least not yet.

 

The CEL (check engine light) comes on when the emission control system is running out of its control range. No rush unless you're environmentally over-sensitive (in which case you wouldn't own a 4Runner anyways), or are due for an emissions test.

Pull the ECU codes with an OBDII reader. If its P0171 or P0172, clean the MAF

 

Toyota does not design "Payday Hooks" into their vehicles.....unlike other manufacturers. If the light comes on in your Toyota....there is something wrong. The severity of what is wrong is then the issue....and that is what you are wanting to know. If you know how to retrieve the codes by putting a jumper on your diagnostic port and then reading the flashing idiot lights codes from your dash....this will tell you what area to check for your problem. Typically when the check engine lights come on in our vehicles it is the O2 sensor (not a big issue just gas mileage will suffer).....however, it could be something else like your intake runner being cracked (bigger issue because unfiltered air could be getting into you engine). The code will tell you what to look for and how severe it is.....and whether you need to get it fixed immediately.

David

 

3rd gens (at least 99+) don't have the jumper-and-read-the-blinky-lights ability for the Emissions System (thank you Toyota weasels). They left this method in for the airbag, ABS and transmission though.

Gotta get an OBDII reader or go to Autozone where they will pull codes for free. And while 'typically its an O2 sensor' may be true for 2nd gens, on the 99+, the P0171 and P0172 codes are extremely common due to a dirty MAF.

 

All cars 1996 and newer you need to use an OBD II reader to check the codes. There are any number of reasons for causing a code and it would be silly to speculate before you which codes are actually being stored in the ECU. Post back when you pull them and we'll help you get it solved pronto.

 

Thanks for the replies,
I may buy an OBD II Code Reader someday, but cant right know due to $1.5K currently going to mods.(yotatech addiction) I have a feeling the sensor may be bad though, it does seem to be guzzling more than the normal feed bag.
I Do like the disconnect battery method to reset and see how long it takes to come back...Anyways hopefully next weekend I will take in somewhere...
Only where to bring her--hmmm- dealership or private.
I would prefer Toyota dealers when it comes to this type of thing but I noticed the local Service guys at Star Toyota were standing outside picketing on strike a few weeks back.

Well I am feeling better now...Thanks
will post with results.

Edit--About the free AutoZone reading--I know AutoZone is not bad in other states but here I wouldn't trust them to tie their own shoes. I only go there for the Anco wiperblades.

 

I'll let you know how my local Autozone does tomorrow.

I just got back form an 800 mile trip and I've got the check engine lamp too. It came on going up a steep hill at 75mph with the cruise set.

I pulled the efi and obd fuses last night and cleared the code. On the way home it did the same thing - steep hill, cruise at 75 = check engine lamp.

I hope it's something simple and AZ can at least give me the right code...

 

yes let me know how it worked out with AutoZone

 

I definately recommend getting a good OBD II code reader for yourself. It will save you alot of headache and also prevent anyone from pulling the wool over your eyes if something goes wrong with the vehicle. You can diagnose on the fly and even reset the code from inside the vehicle. If you have a palm pilot I suggest the one in my signature (about $200) and displays alot of info and is extremely portable (great for roadtrips!!!). The are others for cheaper as well there is also a good laptop based one for $90 (ask mark "midiwall" about it). It is a must have device for anyone serious about working on their vehicle.

 

Well, this AM when I started the truck the light was out. A trip to Autozone showed a stored "P0171 - Bank 1 too lean" code. Connecting the scanner is a no-brainer even for the parts guys there. Just connect it up, turn the key on, and wait for it to display the code.

Looks like I'll try cleaning the MAF when I change plugs tomorrow...

 

Yep.....that be the cure for that one!

 

This just may be a stupid question, but as my mileage has begun to drop and no light has come on, is there a way to CLEAN an O2 sensor like the MAF or does it just need to be replaced?

 

Bad gas mileage is usually a beginning sign that the O2 sensor is on its way out but it can also be a premonition for a host of other things as well. As far as I know there is no practical way to clean it (some have mentioned using a propane torch to heat it up and knock off the deposits). My suggestion is to just get a new one if you are concerned about it as is may have a problem as well which cannot be cleaned off.

I know Mark (midiwall) has a source for cheap O2 sensors online....shoot him a PM.