Hi I have these two codes, I know they are o2 sensor related. Does anyone have a fix for this? I've read up plenty about this but no one has posted an actual fix which is frustrating.

Like an idiot I replaced the sensor believing it was that, but the other side went off with a p2a00 and the the p2a03 came back as well. Now I know it's not a problem with the sensors. In the process of replacing my leaking valve covers as well, not sure if that has anything to do with it. Spark plugs seals are shot too so valve covers will fix that. could this be a reason for the code? Cleaned my k&n filter and maf sensor- no change. Doubled checked for leaks, installed new gaskets- no change.

I do have a full MD exhaust including art pipes. And the k&n and rev up Airbox. Don't want to get a tune at this point.

Any help or advice would be appreciated.

 

so those 2 codes are for your ecu getting a lean condition. if you have checked for leaks in the intake and exhaust side, i would start to check you fuel system. make sure all your injectors are working well, the fuel pump is running well, and the fuel system is getting the proper pressure.

 

Thanks, has anyone else had this specific problem and solved it. Thanks

 

bump - this is a lean code yes but im running rich for sure. gas mileage sucks and a lot of black soot in the tail pipes.

 

I've been struggling with the same code for some time. I had it when I used fast intention test pipes and now with ppe long-tube headers. I thought the code was from an exhaust leak between the manifold and test pipe which is why i got the LTHs. It seems like some people get the code and others don't when using other than stock cats. You can disable the o2 sensors with osiris but that wont pass smog. I would try swapping out your art pipes for stock cats to see if the code goes away. That will let you know the rest of your car is working properly.

 

well of course if the ECU thinks the car is running lean it is going to dump a ton of fuel to protect the engine. also with your mods you really need a tune. cause with all the breather mods it is going to run lean.

 

So I went back to oem cats and exhaust- car is now back to stock. Reset the lights and it comes right back after 30 miles.

Difference is that the code is just p2a03 (Oxygen Sensor Circuit Range/Performance Bank 2 Sensor 1
) comes on at first. Then after hitting around 1000 miles with the ses light on the p2a00 comes back as pending then confirmed.

I did some logging and AT IDLE my long term fuel trims are both .78% on both banks. Short term fuel trim on bank 1 is 25% and on bank 2 is 6.25%. Mass airflow was around .41lb/min.

When crusing steadily - above 65mph. O2 sensor voltages (consistently) are:
b1s1- .20V
b2s1- .66V
b1s2- .04V
b2s2- .89V
LTFT1- 7.03
LTFT2- 3.91

Does this indicate a problem with b1s2 o2 sensor? Im trying to pass emissions this week so I need all the help I can get.
Thanks guys.

 

After replacing the sensor, did you go through the self-learning process? If not, give it a try.

http://infinitihelp.com/diy/gcoupe/p...f_learning.php

 

I'm having the same code p2a03 **** is a pain in the *** how would I check the fuel injectors and fuel system

 

Still going through this- replaced both sensors now. No leaks according to my mechanic.

Checked Maf with one off a different car.

We are thinking clogged Cat as the code is now just reading P2A03 on the one side.

 

That's not a lean code per se. It means your sensor is measuring either rich or lean. Yes, it can be caused by leaks.

Did the mechanic use a smoke machine to check for leaks? It could be intake leak or exhaust leak.

Did you verify the wiring and check for voltages at the sensor wires?

The pin out for bank 2 sensor is:

531
642

You'll need to backprobe the wires and a mutlimeter to do these checks:

Terminal 1 and ground - 3.1 V
Terminal 2 and ground - 2.3 V
Terminal 5 and ground - 2.6 V
Terminal 6 and ground - 2.3 V

The last wire you can use a multimeter, but you actually need an oscilliscope to look at the wave pattern:

Terminal 4 and ground - 5 V - It should be a square wave I believe.

You can test for an exhaust restriction or clogged CAT just by using a vacuum gauge and it should sit around 22-23 at idle I think. The needle should be steady and not bouncing then raise the RPM up to like 2000RPM and it should be steady as well. If you go WOT the vacuum should drop down to 0 and then return to 22-23 really quick. When I had a huge intake leak the needle would bounce from 22 down to 18 then back up to 22 like clock work just sitting at idle. You can attach a vacuum gauge at the plenum where the little nipple sticks out.

To check for exhaust leaks, I usually use SeaFoam at night, so I don't anger my neighbors. You can use a smoke machine, but that was the easiest for me and the smoke came out from where my exhaust was leaking.

I think you should find a mechanic who isn't just going to take guesses and keep throwing parts at it.