Ever since my engine rebuild, I've been seeing this code show up off and on, sometimes triggering a SES light. It's always code P0175.

Factors:

1. Engine recently replaced (longblock assy) GT 5.4 block, stage 2.5 heads, 2.5 cams, JDM spec.
2. Longtubes/midpipes (Dynatech)
3. 60# injectors, Walbro 255LPH pumps.
4. SCT 2400 MAF (6V version)

Observations:
The engine seemingly runs ok, however whenever the A/C is on, the idle will cycle - drop to the point where the engine is at the verge of dying when the compressor is running.

The TPS voltage measures out at 1.03-1.04V fully closed. I don't know if my tuner set this or not as an offset to the cam lope at idle. Perhaps someone knows if the TPS settings should ever be higher than .98-.99V closed?

All vaccum connectors are in place. The tuner/installer and I went over this several times.

I did a search and seen that a couple of others with similar mods (Odin's Wrath, Madfestarri) threw this code, but there wasn't any reported resolution....

Any help with this is greatly appreciated. My local tuner's out of town right now.

JC

 

???

 

Isn't that a lean bank code?

 

The expanded code is Bank 2 too rich. I think p0174 is the same thing for bank 1
.

 

I have my TPS set at .98 volts. I have an iron block JDM longblock with cams and it idles fine running the AC or not. The only quirk I notice is it idles down a little going from Drive to Reverse but not major enough to feel like it's going to stall. I'm running a JDM tune.

 

Hmm. I'll recalibrate the TPS for .98V. I have no idea what the tolerance for the TPS - I've heard that you only want to see .98-.99V and nothing else! 2 hundreths of a volt tolerance for something on a vehicle like ours seems mighty thin!