richonline

Hello everybody,

As I mentioned in the previous post, I just cleaned the MAF and IACV. But after a day of driving, got the problem: the CEL, TRAC OFF and VSC are all ON now. Pull the code and it is P1130, which seems to be bank 1 sensor 1.

The car was running fine, no code or problem. I just wanted to get it cleaned. Do you guys have any idea, if the code could be related to the cleaning of MAF or IACV? Or the sensor is actually bad? Thanks a ton.

Lexmex

Tough to say.

Generally if you keep getting that or another code related to the A/F sensors after a while it usually means the sensor is bad or is going bad (getting deteriorated). I have not had an A/F sensor code since I replaced mine recently, but before I replaced them, I would get the codes more often (particularly on bank 1, sensor 1), until I finally replaced them (Mexican gas was atrocious on these sensors).

I'd wait until another tank of gas to see if anything changed, as sometimes the vehicle does not need time to adapt following a cleaning of the MAF or IACV, or you could just disconnect the battery cables and reset the system and drive a bit and see if any change.

richonline

Thanks Lexmex. We are all glad you are always willing to help.

I did reset the EFI fuse after the cleaning. I even reassembled the IACV and MAF after I got the code. But not helpful. I guess I will wait a little to see if it goes away. Or use the scanner to erase it. Hopefully not have to deal with the a/f sensor coz it was working fine before the cleaning and not sure if it is really bad now after the cleaning.

Lexmex

I'd also run a can of injector cleaner (I do this roughly every 3000 miles), because even thought the IACV and the MAF is clean, the injectors are in there same condition and may not be 'in line' with the a/f ratio. The sensor may indeed be amiss though.

richonline

Thanks again Lexmex. I think adding some injector cleaner is a great idea. Considering how the a/f sensors perform before and after the cleaning, I do believe the a/f sensor or injector is not in line with the 'new' MAF and IACV. Can you tell me what brand of injector you normally use and where can I get it?

BTW, I did erased the code yesterday, but two fault codes P1130, P1150 and one pending code P1130 (same 1130) came back in 20 miles. So I erased them again last night, will see what happens.

Lexmex

I experiment from time to time, but generally Redline Fuel System Cleaner. Only place I see this at is Pep Boys. Otherwise Lucas or Techron from Chevron are common everyhwere.

richonline

Thanks again. Will get tomorrow. BTW, the annoying codes came back again.

Nad1370

Probably just coincidence that the code popped up after the service.

P1130 --A/F Sensor Circuit Range/Performance Malfunction
(Bank 1 Sensor 1)

Meaning--Voltage output* of A/F sensor remains at 3.8 V or more, or 2.8
V or less, during engine running after the engine is warmed up.
Or A/F sensor does not change from 3.30 V, during engine running after the engine is warmed up(2 trip detection logic).
You need a diagnostic tester that reads AF voltage to confirm this.

But more than likely it's a bad A/F sensor. Time to get your hands dirty.

Running injector cleaner is a good move but it won't fix your P1130 code.

richonline

Thanks Nad. When the codes came back this time, I only have the fault 1130 and the pending 1130. The 1150 code is gone. So maybe the a/f sensor is really bad. Also I noted the mpg did get reduced by 1-2%, not much, but...

Could you suggest where I can get the AF voltage read, autozone? I only have a scanner. Also thanks for the clear pic demo.

[QUOTE=Nad1370;5923344]Probably just coincidence that the code popped up after the service.

P1130 --A/F Sensor Circuit Range/Performance Malfunction
(Bank 1 Sensor 1)

Meaning--Voltage output* of A/F sensor remains at 3.8 V or more, or 2.8

bearbrew

NAD1370,

The picture sure makes it look like the sensor and connector are wide open and easy to access. Although, it is not that difficult, a little patience goes a long way when replacing the sensor. The electrical connector took the most time for me to disconnect. It was still a fairly easy job.

richonline

After reading a lit more on other site, I am willing to believe the fault codes came because the cleaned MAF and IACV. It seems after the cleaning, the a/f sensor couldn't adopt to the 'new' MAF or IACV. The problem with the a/f sensors on my car might be there before.

Another common problem people have is that after they changed one of the two a/f sensors, the other one gave the fault code. Somehow make sense in my view. How you guys think?

richonline

Just an update: after adding the Techron, the codes have not come back in 80 miles. Hope it can last. Thank Lexmex and you all for the help.

Update on 11/12/2010: Ok, it's been 200 miles and no code yet. Cross finger.