breakerfalls

My check engine light is on, and I used the diagnostic box to check the code and it came up as a code 25 and a code 26. Code 25 is air/fuel ratio lean, and code 26 is air/fuel ratio rich.

I just had an oxygen sensor replaced, but according to the dealership there is a second one crammed somewhere up in there that I can't see.

I also removed the intake elbow and bought a drop in K&N filter recently as well.

Is there anything else it could be other than the oxygen sensor? I'm going to buy some contact cleaner tomorrow and clean the MAF to see if that helps. Any other suggestions before I shell out the cash to replace the other oxygen sensor?

Thanks,
Keith

CTB

We don't have a MAF sensor you can clean. Instead, we have a AFM (air-fuel meter), and I don't believe it can be cleaned like the MAF on 3rd Gen's. I would try cleaning my throttle body really well first to see if that helped at all, and then maybe run a can of Techron fuel injector cleaner through the system as well. The last thing I would try is to replace an expensive oxygen sensor...Good luck.

Troudt

I had a similar problem after I had the dealer change my o2 sensor. I ended up taking it to 2 dealers before I took it to the shop I go to now. When the 1st dealer put in the o2 sensor the disconnected a vacuum line. Since dealers don't look under the hood they just check the codes they would say it was an o2 sensor. I spent a couple months trying to figure out the problem.

AgRunner06

I'm pretty sure that you only have one O2 sensor unless your vehicle is from Cali. So you might keep that in mind when the dealership wants to replace your "other" O2 sensor.

That seems kind of weird that you would get a lean and rich code at the same time. Maybe those two codes happened at different times but were still stored in the computer. You need to reset your computer by yanking the EFI fuse for 10 minutes. Then wait for your CE light to come on again and get the code out of it. My bet is that you will only get one or the other and not both the lean and rich code. But I could be wrong...

Good Luck

breakerfalls

Thanks for all the suggestions, but it looks like I'm going to have to have my shop tell me whats wrong with it.

I already ran some fuel injector cleaner through, as well as a tank of premium gas just for the hell of it. I tried pulling the EFI fuse but still got the same two codes. Being the bull headed idiot that I am I tried to clean the AMF.

WORST MISTAKE EVER.

Apparently there are some very fragile wires in there because i unscrewed it and just barely pulled it out a little and they all popped off. I couldn't get it plugged back in, so now my runners at the shop down the street. They couldn't sodder it back together, so they are telling me I have to buy an entire new airbox. They found one at a junkyard and it's 120 bucks.

For anyone reading this in the archives in the future, don't be like me and screw with things before you know exactly what you are doing.

-Keith

MTL_4runner

Sorry to hear about that, if we knew you were going to disassemble your AFM we would have warned you first. I am sure you will get it back up and running soon though.

For those reading this in the future AFMs have an adjustment but never pull them apart to clean.
Only MAFs need to be cleaned as such.