Error Codes In Succession P0171, P0135, P1130, But Not At The Same Tim

[ireallyhateusernames]

Hi all,

Last year, I had a P0171 code pop up. Being cheap and all, I threw some engine cleaner in a tank of gas and it went away (yay!). About a month or so ago, I got another check engine light, and the same code came up. I thought I finally needed to replace the sensor (and I put another bottle of engine cleaner in the tank for good measure), but upon checking this forum, I found that most people reported it was caused by a dirty MAF sensor and the recommendation was to clean it with an electronic parts cleaner. So I did that today and I put the OBDII reader on to clear the codes to see if it would take, but first I ran a test to see if there were any other new codes. The P0171 code was now gone and replaced by P0135. Looking that up it had something to do with water and as my radiator fluid was a bit on the low side, I thought that maybe the second round of engine cleaner had cleaned it up and removed the P0171, and the CEL was being caused by low radiator fluid (I don't drive that often). So I topped off the radiator and cleared the codes.

I took it for a short drive and the CEL came back on. This time when I put the meter on it, it's reading a P1130. When I looked that code up for the RX300, it says it's related to the MAF (a short), but in the generic book I have with the meter, it's coming up HO2 sensor. First, I'm confused as to what this error code is referring to. Second, did I destroy my MAF sensor by cleaning it? It was dry as far as I can tell, but I guess there is a possibility that it could have been a little damp way inside (however far inside it goes).

Pretending it was damp, would this error fix itself once the unit completely dries, or did I destroy it? Does the MAF have a fuse attached to it that may have been tripped. If so, where is it located? How can I go about testing the MAF to see if it's good (because I don't want to replace it and 3 O2 sensors for nothing). I have an electronic multimeter for testing volts, ohms, resistance, etc, but what are the numbers that I'm looking for and how do I go about testing it exactly?

Any help in this regard would be greatly appreciated, as I don't really have a mechanic I can count on and I need to figure this out.

:)

[smooth1]

When you put the ODB scanner on, are you looking at the pending code listing? Or did the ECU actually throw up another cel? Keep in mind that the ECU is not a waring system, but a datalogging and engine adjustment and control device. The ECU will log events, and if the event is outside the set parameters and it happens x amount of times within a set time span, then it throws up the cel.

When you cleaned the MAF did you touch the elements? Or just spray electronics cleaner on it? When you put it back together, are you sure you did so correctly?

[SKperformance]

Let the engine run normally to heat it up and clean it up, you either have a bad maf, a broken egr tube or bad o2 sensor.

[ireallyhateusernames]

When you put the ODB scanner on, are you looking at the pending code listing? Or did the ECU actually throw up another cel? Keep in mind that the ECU is not a waring system, but a datalogging and engine adjustment and control device. The ECU will log events, and if the event is outside the set parameters and it happens x amount of times within a set time span, then it throws up the cel.

When you cleaned the MAF did you touch the elements? Or just spray electronics cleaner on it? When you put it back together, are you sure you did so correctly?

I had a CEL for the initial code, that being the P0171 a little over a month ago. When I cleaned the MAF and put the meter on, it was replaced by P0135. The CEL had remained on for all that time, so I'm not sure if the gas cleaner I put into the tank fixed the P0171, and then I later had a P0135 code or what happened, but the CEL didn't go off and come back on, it was solid for the month.

Then I cleared it and ran the car and another CEL came up, this time when I put the meter on it gave me P1130. I didn't touch any of the elements, I just sprayed electronics cleaner on it. I'm pretty sure i put it back together right, it was just 2 screws and a plug. I did take that engine cover off (the one with the Lexus emblem) to check the wires and see if there was anything under there that might have been off, could I have banged something under that? Pretty much all I did was look under there, clean the MAF, replace the air filter, and jiggle all the hoses to see if they needed replacement.

I finally got a hold of my mechanic and he recommended I take it for a highway drive, which I plan to do after the snow has passed through. He seems to think it will magically resolve itself, which I hope it does. I'll let you all know if any other codes pop up or go off. Thanks for the responses.

Pam

[ireallyhateusernames]

So, I took the beast for a highway drive, rechecked the MAF sensor plug (in case I put it on wrong), then put the scan tool back on it. What I have showing up now is P0125, P1130, P1135. I've looked up the codes and they all seem to deal with Bank 1 A/F sensor. This is different from the O2 sensor, right? Other than a bad A/F sensor, is there anything else that can be bringing these codes up, say something really easy to fix with a cleaner or prayer? If it is a bad sensor, is there anything special I need to look for when I go to get the part?

Thanks so much for all of your help!

Pam

[lenore]

Bank 1 and Bank 2 sensors are wired in series for the heater on the oxygen sensors, however you could have just one code. Check continuity on both band sensors on the black wires and make sure there is resistance. If one is open both will not heat up. Just one little tip.