2000 Avalon - Check Engine Light

[Cherrybark]

Codes P0125, P1130 and P1135.

I've read several threads on the MAF and O2 sensors. I'm hoping my code combination will help someone narrow down the problem rather than simply replacing the MAF and sensors all at once.

The car has just over 70K miles. About a year ago it had check engine light. Cleaning the MAF corrected that problem and in the process I learned about tightening the fuel cap, not topping off, etc.

This time the MAF looked fairly clean but I gave it a couple of shots of brake cleaner and shined with a Q Tip. The air cleaner was replaced about three months back and still looks new. I don't hear any vacuum lines sucking. The temperature gauge shows the engine warming up normally. After the light came on I filled up the tank to get idea of any change in mileage. I also popped the two fuses to reset the light. I came back on after five minutes of driving.

Other than the light, the only indication of a problem is occasional very rough running at idle. I assume the computer is confused by a bad sensor and is incorrectly setting the timing or fuel mixture or whatever magic computers do in cars these days.

Is there any way to test the MAF or sensors? Or is this so complex that a shade tree mechanic just replaces them in a logical order? Can anyone suggest what that order might be?

Is there a favored source for ordering Toyota parts over the web?

Thanks in advance,

Carl

[73mach1429]

Those codes point to a bad Bank 1 A/f sensor, not a MAF. Bank 1 is closest to the firewall.

[nebrhahe53]

How do you determine the codes? is there a peoduct i can buy that will let me diagnose issues like this? Thanks

[ToyzOnly]

Originally Posted by nebrhahe53

How do you determine the codes? is there a peoduct i can buy that will let me diagnose issues like this? Thanks

Yepper. OBD II Code Reader:
They have 'em at most auto parts stores.
I hope the link below works for ya. If not call just about ANY auto parts store.
To get an idea of what I'm referring to, click on the link below:
click here

[LifeTech]

I don't use 'Brake Cleaner' on Electrical parts.
Yu state that yu did. Any reason why yu used Brake cleaner on the MAF?

That's how yu WILL damage and reduce its life, if it isn't toast already.
Either use MAF Specific Cleaner (like CRC Brand)or any Electrical contact cleaner spray.

Brake cleaner will damage the plastic and resin adhesives in a MAF sensor.
Your MAF "heater" could be Junk now! Especially if A/F ratio seems 'off'.
An indication of this.

LT