Replaced Air Fuel Sensor(front manifold) with Toyota Part #89467-48011 and cleared CEL light. Light has not come back on. Code reader had read codes P 0100, P 0110 and P 1155

 

Momscar- I would always suggest to clear the codes 1st and then see what codes come back up. You may very well find that the same codes do not come up the second time around, or at least not all of them. If you clear them, see what code(s) come up 1st and respond to that, it may be more accurate. Your other codes (P0100) refers to mass or volume air flow circuit malfunction. The (P0110) refers to intake air temp. circuit malfunction. I would say it would be a little unusual for the MAF and the A/F ratio sensor to go bad at the same time. Check the continuity (or ohms) on the 2 black wires in the A/F sensor you took out. Since that code (P1155) refers to the function of the heater, that will tell you if the heater is bad in the sensor. Remember that most codes take at least a little while to come back up when they've been cleared, so the CEL may come back or may not. It still wouldn't explain the other 2 codes. Good Luck!

 

Maybe I am unsure about the grammar, but he may have been implying that he had the codes previously and now he doesn't.

You know what I am still amazed at, I still have my OEM sensors after all the garbage they've been through in Mexico and still running.

 

I believed you mentioned that exhaust heat cooked these sensors. I think you are probably right since you get more air flow to cool things down, just another good reason to speed

My front A/F sensor lasted almost 40K miles longer than the one near firewall. Oxygen sensor after the cat on our car last the longest, perhaps because it is outside of engine bay and endure lower temperature.

Shop manual indicated one has to remove driver seat to change oxygen sensor.

 

That's entirely possible LM. Sometimes (read probably most-LOL) I get a little too detailed, but I am a detail person by nature- I don't like uncertainty.

 

You can call me crazy,But that is probably one of the reasons the a/f`s last longer on premium fuel. Lower exhaust temps.due to the ignition timing NOT being in a retard status.

 

Actually higher octane gasoline enable the engine to retard ignition because the compessed air fuel mixture can hold on and not explode until spark spark ignites.

Also remember A/F sensor detect exhaust gas that is burned, not the status of mixture in the engine (knock sensor does that job).

 

I still have my original sensors at 109K. I would have expected them to be replaced well before my knock sensors. And, I would have certainly preferred to replace the a/f's instead of knock sensors!

 

Tuned,with all due respect that doesnt make any sense.The Premium fuel allows the motor to run at its optimum mapped (via the ecm) timing.The only reason the timing would be retard,is if it detects pinging.And it certainly should not ping on 91 or higher octane,or there are other problems occurring some where else.Bottom line is,it retards timing when pinging is detected.Higher exhaust temps.occur when timing is retard,not the other way around.Let me tell you a short story of when I was a teenager,my friends thought they would play a little trick on me.I was with my girl friend one evening (a stay over her parents were cool))and the next morning when I got in my pristine 1971 Ford Maverick w/200cid straight six motor to go home.At first the car didnt want to start,then I finally got it started and it was running like total crap.all the sudden my air shock lines were melted,and the car went back to its stock stance.I drove it home that way running like garbage,just for giggles I advanced my distributor because to me it seemed like the timing was way off.Well I was right,during the night my buddies admitted they pulled a prank and retarded my ignition timing,yeah real funny!.Not only did the cars exhaust pipe get so hot it melted my air shock lines,it also burned an exhaust valve very badly.(had to replace it) I got to see first hand (what an extreme case mind you)of retarded timing will do.