Codes
 

Hey Everyone,

I am getting a couple of codes:

P2A00 02 bank1 sensor1 range/performance
P2A03 02 bank2 sensor1 range/performance

I have Stillen G3, MXP TP, and FI CBE. After talking with some nissan techs (they have not seen the car, this is their guess) they are saying that the oil from the CIA filters have messed up my mafs. But this would be the first that I have heard of this problem. I would like to get some input before return the car to stock to bring it in.

Is it possible I am throwing these codes for lean/rich from being untuned? Anyone else getting these codes? Input would be greatly appreciated.

Did you recently service the K&N filters (clean and re-oil)? I've read if you "over-oil" some of that can get onto the MAF sensors. However, you could try to wipe them clean with a good microfibre cloth and see if it happens again. Some member have reported this and that's what they have done. I'm pretty sure it's not a rich/lean condition.

It could be a number of things really. I wouldn't expect bolt-ons causing lean/rich conditions to throw this code. The code is basically saying your wideband oxygen sensors (not the emissions ones blocked off in your testpipes, the front ones in the exhaust manifold/header) are responding too slowly relative to the fuel trims, which supposedly indicates a deteriorating oxygen sensor.

However, you're getting it in both banks and unless you've done something horrible to foul the sensors (leaded fuel, something like that?), that seems unlikely. It could be, as they said, the MAFs having problems, which could lead to problems with fuel trims, which could convince the ECU of O2 sensor issues. It shouldn't be from oil on the filters though, unless you've cleaned them yourself and applied way too much oil at the end of the process.

It could also be any number of simpler things, like an intake and/or vacuum leak somewhere.

The best clues will be to look back at the car's history leading up to the codes appearing. It takes a couple of drive cycles for a code like this to show up usually. What was the most recent work done on the car? Was anything done within a few days/drives of the codes appearing?

The car was stored all winter in a heated parkade with car cover. These codes are new and the mods were all on the car last year...

I'll recheck everything to make sure nothing has come loose over the winter, thanks for the input.

Looks like it might be a air intake leak after the MAF's causing a lean condition. Or there is oil on the MAf sensors. Clean them with some contact cleaner and see if it improves. So the service manual seems to indicate.

Stop by this weekend and I can have a look at it. I have lots of contact cleaner on hand :tup:

It's the test pipes. The MXP ones look like they have a very short bung for the 2nd sensor, you might have to use extenders with steel wool stuffed tightly inside them. This is one of the reasons I prefer HFC's.

The test pipes have extenders on them already. The code is coming from the o2 sensors in the manifolds, not the TP. I wish it was that simple haha.

Llyod, thanks for the offer. I'll let you know if I can stop by this weekend. I sprayed the mafs with brake clean but the codes came back. I am going to take the whole intake system apart to see if I can find any leaks or perhaps a hole that has rubbed through.

I have had the air tube intake rubber connector on the throttle bodies be loose and mis-aligned, causing a air leak into the manifold. I'd check there first before looking at the manifold connections.

I just hope you don't have a cracked manifold :eek:

Yeah that would cause a vacuum leak as well. I believe he's talking about the tiny EVAP hose connections, one on the rear of each throttle body. Double-check PCV connections too (two tubes going to the front little inlets of the manifold).

A good way to check for vacuum leaks in general that I've seen posted elsewhere on this board: with the car running, spray something with a relatively safe solvent and/or fuel mix all around the intake manifold area (e.g. brake cleaner made from acetone/methanol/etc. Or maybe a safer solution would be a spray can of Engine Starting Fluid). If there's a vacuum leak, it will suck that stuff in and combust it, and you'll hear a change in the car's idle speed or whatever. Be careful of the fire hazard spraying that stuff around hot metal though.

I realize the code is coming from the upstream sensor, but sometimes these codes can be misleading. If you have test pipes and you haven't used any filter material on the downstream sensor then the computer will throw codes. The typical code will be for cat efficiency warning but you can get different ones showing up. That would be the first thing I try before pulling the whole intake system apart.

You still have stock exhaust manifold correct?

I doubt it could be an over oiling issue with the CAI. They would have to really soaked in oil to make it to the MAF Sensors. I would suggest clearing the codes if you havn't already and drive it for a while. It might just be a gremlin from sitting too long in the winter.

I'm getting the P2A00 code, after multiple re-sets. I have stock cats though. So, my guess is with what WStar said. I had a previous problem with my O2 sensor after installing the stillen headers. So I'd say they'd have to be checked/replaced, which is a giant pain the *** because of how unnecessarily expensive they are.