I figured I would consult the experts because I am on a time crunch to pass emissions.

If I missed any crucial information please consult the pictures and info here in my build thread, hopefully the necessary info is in there. If not, I will be checking my email diligently.

http://g35driver.com/forums/media-sh...sip1115-5.html

2005 G35 Sedan, non rev-up, Greddy TT, boost referenced RFS, 570CC injectors, GT MAF, much more.

A few hours after washing the engine bay my car threw P0158 and P0138 along with P1000 and a code for the steering angle sensor but that has not come back. I started by checking engine grounds and adding more grounds from the exhaust to the body, the engine to the battery, and adding a second from the battery negative to the body.

After doing this, and checking over all of my front/rear O2 sensor wiring I took it for a spin. Now I'm down to just P0158. the other codes could be on their way back I suppose, I only put about 20 miles on it since the most recent reset because I do not like driving a car that runs lean.

On Saturday night I was in the 16's on my AFR gauge during partial throttle vacuum cruising on the highway, so I re-calibrated the sensor but am still getting lean readings under boost. It doesn't seem to be quite as lean anymore under vacuum. Not sure about boost, all I can see is that it is cutting boost because of my preset safety parameters.

The car is running lean when boost comes in, and I'm pretty sure it is running lean under vacuum too (up to 15.3 at idle, not consistently). My innovative wideband/boost controller is a life saver and is telling me that my AFR is going over 12.8 at 4.5PSI. I love that thing...

My plans to troubleshoot when I get time this week are as follows:

Clean MAF sensor
Check drivers side O2 sensor wiring and clean all contacts related to
Check fuel pressure
Check for Vacuum leaks at the FPR


My question is; how finicky are the uprev GT MAF sensors? Unfortunately for me the sensor is in the charge tube so it most likely did not get wet at all... Perhaps some water got into the turbos and "steam cleaned" the charge pipes, coating the MAF. Dunno! Where would you guys go from here? I checked all of my fuses in all three boxes, none were popped. I have cipher and plan to plug in to see what I find on Thursday night. Any help or things I should check would be appreciated because my emissions due date is on Saturday

Thanks for reading!

 

so I ran through all of the checks I said I would, everything passed. I took it for a spin and noticed I only lean out at partial throttle. At WOT my AFR stays steady where it needs to be and doesn't cause boost cut at all. I am thinking that when I hit boost cut it makes the AFR so rich that it throws the codes for the rear o2 sensors being out of range (rich, not cat inefficiency). Knowing it is only at partial throttle, would that lead to one of the front O2 sensors being bad? They are literally 1300 miles old, but I guess one could have gotten wet or something when I was washing the bay. Anybody else agree I should focus there?

Edit: I am having p0138 and p0158 spit at me after boost cut kicks in, not just p0138. Symptom: leaner than it should be at partial throttle when boost comes in. Root cause; unknown.