Anyone able to code out 02 sensors and MAF CEL?

[nitrorocket]

I have my car tuned with gutted pre cats. I need to get my precat o2 sensors and MAF overlimit codes removed so I can go through emissions. Been driving with the CEL on and no registration for a long time now, need fixed.

Thanks

[ttboost]

You cannot code out front O2's and MAF's. Those are the only thing keeping the car running right. Rear O2's can be coded out. Have you scanned for codes?

[nitrorocket]

Yes, I have the codes are P0103, P0174, P1455. P0420, P0430.

None of these came up until the moment I had the reflash.

[hahnmgh63]

P0174-too lean Bank2, EGT1, these you should not have. The P0103 can be avoided before your test by clearing the code and driving the car easily for the minimum mileage needed before the test, something like 20 or 30 miles after clearing codes before they will usually let you test. The P0420 & P0430 can be fixed by coding out your rear O2's. You shouldn't be getting the 'too lean bank 2' or the EGT1 codes. Who did your tune? How many miles on the car?

[nitrorocket]

I have 130k on the car, not one code up until the day it was tuned, I don't want to say who tuned it, he is trying to work on a fix for the problem, but seems to be having trouble. So I am looking for anyone who can tune the o2's out...

I have winols, but have no clue how to use it, and cannot read german. Lol

[10SecS4]

Are you sure it's P0174 and not P1074? P1074 is the same as your P0103 code except for the other bank.


Yes, I have the codes are P0103, P0174, P1455. P0420, P0430.

None of these came up until the moment I had the reflash.

[lswing]

I'll get front O2 and EGT intermittent when running lean and hot....you can cook those egt's costing you $, and the O2's might not like it much. Since you're playing with fire, and seem to have VAGCOM, go log Timing, EGT's, and Lambda values, will let you know if the tune is wreaking havoc. Also could just be old plugs or fuel filter inhibiting a good strong tune, or....

[nitrorocket]

Marc, it is P1074, apparently I need to work on my typing skills. haha.

[nitrorocket]

It's not because the car is running hot, I can drive around normal at part throttle and though codes will come back driving without boost. The MAF code only comes on when I'm boosting hard.

Anybody able to code out the O2 sensors?

Either that, or I need to put my computer back to stock so I can get through omissions. Not really thrilled about driving around in an unregistered car anymore That has a check engine light on all the time.

[lswing]

It's not because the car is running hot, I can drive around normal at part throttle and though codes will come back driving without boost. The MAF code only comes on when I'm boosting hard.

Anybody able to code out the O2 sensors?


You should log data, and find then fix the problem, it would help your car greatly. Why would you code out a sensor that is trying to help you? Plus you'll get better performance with the car buttoned up...

If it's just MAF maybe it's a small leak, sometimes a good shop can fix you up quick!

[nitrorocket]

It's not because the car is running hot, I can drive around normal at part throttle and though codes will come back driving without boost. The MAF code only comes on when I'm boosting hard.

Anybody able to code out the O2 sensors?

Either that, or I need to put my computer back to stock so I can get through omissions. Not really thrilled about driving around in an unregistered car anymore That has a check engine light on all the time.

[nitrorocket]

Its not a problem with the car, none of these codes were active until the day I installed the flased ECU.

[lswing]

Its not a problem with the car, none of these codes were active until the day I installed the flased ECU.

The tune will ask more for the car, therefore exposing problems such as an air leak. What tune is it? If you're that unsure of the tuner I would pull it from the car anyhow, but it's a problem with the car is my guess.

If you're not logging data to see just what is going on you're playing with fire...

[10SecS4]

He's not playing with fire because his code was P1074 not P0174. His codes are for the two rear O2s (since he gutted the pre-cats) and signal too high for the MAFs which is common for a strong tune since it's running the maximum airflow for the stock sensors.


The tune will ask more for the car, therefore exposing problems such as an air leak. What tune is it? If you're that unsure of the tuner I would pull it from the car anyhow, but it's a problem with the car is my guess.

If you're not logging data to see just what is going on you're playing with fire...

[lswing]

He's not playing with fire because his code was P1074 not P0174. His codes are for the two rear O2s (since he gutted the pre-cats) and signal too high for the MAFs which is common for a strong tune since it's running the maximum airflow for the stock sensors.

Got it, seems like an easy fix then. So why the problems? Just code out the rear O2's which is standard, and don't flog the car for a few miles after clearing codes as mentioned.

Actually first time in years I've heard about the MAF exceeding because of a strong tune. Lots of people seem to have their car tuned to the edge without this issue. Again, would be nice to see a log...

Edit; Boost leak is a common reason for the MAF code...

[G2]

Won't that be for naught, when actual tailpipe emissions are measured during the test?

The PPM counts will be drastically higher w/o a functioning cat. system. Can't see how turning off the MIL (not CEL folks, that's domestic auto talk there!) light is going to help much. At least the AWD system makes it exempt for a loaded dyno test.

Either way seems a shame to pollute 10 to 100X more just for a few more HP.........

[hahnmgh63]

Believe it or not, most states, including across the border here in Washington just plug into the OBDII port and don't even sniff the exhaust on an OBDII car. Some are stricter and do the sniff test and a couple even do the above and below visual inspection looking for modifications.