Po171 Code

[cyberflyer]

The CEL on my '98 ES300 came on with a code PO171 ( System Too Lean Bank 1). The outside temp was in the 90's. I read the post about cleaning the MAF sensor with Q-tip and alcohol. Before I could do this the CEL light want off and has remained off. Is this unusual or did the hot intake air cause the problem. Do OBD codes reset themselves?

Any ideas?

[SKperformance]

They do not reset themselves if the problem goes away just turn the light off but stores the code for future diagnosis .

[Lexlogic]

The CEL on my '98 ES300 came on with a code PO171 ( System Too Lean Bank 1). The outside temp was in the 90's. I read the post about cleaning the MAF sensor with Q-tip and alcohol. Before I could do this the CEL light want off and has remained off. Is this unusual or did the hot intake air cause the problem. Do OBD codes reset themselves?

Any ideas?

According to the 2000-2001 ES300 repair manual, here are the trouble areas for the P0171 error code:

- air induction system

- fuel injector blockage

- MAF meter

- engine coolant temp. sensor

- fuel pressure

- gas leak on exhaust system

- open or short in Bank 1, 2 Sensor 1 circuit

- ECM

For most people who encounter this particular error code, the problem lies in the pre-cat oxygen sensor. There are 2 sensors located before the catalytic converter, and either one or both of them could be delivering a bad circuit. You're going to have to get the resistances tested with a multimeter and see if the resistance meets spec. That's what I would do to determine the bad sensor. Or if you prefer, you can take your car to an independent service shop who is familiar with Lexus/Toyota vehicles and get the sensor(s) diagnosed. Hope this info helps out

[lexusk8]

^^ Hey, that's exactly the same response I wrote to you when you posted your problem with the fuel system in your ES (original reply here). I see no credit given for my write-up. Are you going to plagarize with somebody else's work and claim that it's your own?

[steviej]

^^ Hey, that's exactly the same response I wrote to you when you posted your problem with the fuel system in your ES (original reply here). I see no credit given for my write-up. Are you going to plagarize with somebody else's work and claim that it's your own?

evidentally Lexlogic isn't aware of cyber etiquette yet. not cool. :whistles:

steviej

[Lexlogic]

^^ Hey, that's exactly the same response I wrote to you when you posted your problem with the fuel system in your ES (original reply here). I see no credit given for my write-up. Are you going to plagarize with somebody else's work and claim that it's your own?

Sorry! I took notes and try to share it to whom needs help. I did not know where I copy this information from but do you have picture that could be share to this 98 ES300 problem. Thanks