p0171 and p0175
bank 1 too lean and bank 2 too rich
these codes dont make sence to me, this vehicle has a commonrail fuel system and a connected intake.

the engine lacks power so much so that it is undrivable. it hesitates and stumbles, it has yet to stall but acts like it wants to.

I have checked the maf and it is working properly.
I have removed both cats and saw no change.
I have tested vacuum and am seeing 15hg steady.
I have pressure tested the cooling system and am losing no coolant.
I have seen no smoke with the cats removed so I am doubtful of bad rings or head gaskets.
The engine idles steady, it almost feels like a terrible misfire but the lack of misfire codes leads me to think otherwise.
It will routinely act as if I am not applying throttle when I am.

I need to know how much vacuum this engine should generate at idle,
what numbers should a working tps read?
How dangerous is spark plug removal on this engine?

Any thoughts suggestions or ideas?
thank you,
Benjamin

 

Vacuum should be right around 20 Hg.
Did you test the fuel pressure, if so, what was the PSI?

 

Beins this is a 3 valve engine, spark removal can be a pain, but i can give u some tricks that will help if u r interested. Is p0171 and 175 the only codes? I dont believe i have ever seen this problem. a rich and lean code set at the same time for the same bank. that is odd...i wouldnt think it would be fuel supply related beins its on 1 bank instead of both. But i could see fuel delivery to cause this issue. I have seen alot of trouble with injectors in this engine, but u normally have a missfire code such as p03xx depending on which cylinder is missing. I would recommend pulling the fuel rail up out of the intake. Leave the fuel lines connected to the rail and have some one turn the key on while u watch the injectors. There should not be any fuel to come out of the injectors with KOEO. If an injector does leak fuel replace it....
I have seen the electronic throttle bodies due some weird things as well, but they normally set dtc's as well/
I would also recommend watching the o2's and see what they r doing. R they running rich and then lean on bank1? What is really happening? U could have a PCM issue as well... Hope this helps

 

its not on the same bank its on 2 seperate banks.
p0171- bank 1 too lean
p0175- bank 2 too rich

I have not tested fuel pressure, I will tomorrow what numbers am i looking for?

I have heard that faulty tps's can cause odd sympoms on these vehicles, could that be a suspect?

And as for the spark plugs Im more referring to the likelyhood of stripping threads/ breaking plugs. Ive heard that the issue was addressed by the 2006 model year but I would like confirmation.

Thanks Guys

 

I thought only politicians give two completely opposite answers to the same question.

 

Noooooooo ... unfortunately, 2007 was the year it was finally addressed.

 

Ok fuel pressure is around 50 primed and 45 at idle.
Did a fuel seperation test, no water in fuel.

still stumped....

 

How about the problematic PCV hose elbow at the rear of the intake? Have you inspected that for clogs, cracks, or breaks?

 

OOPS my bad. Brain fart. mk lean on bank 1 rich on bank 2 my bad. Thank you for correcting me...

 

Fuel supply and fuel delivery are 2 separate systems, if thats what ur fussin bout.

Fuel supply= fuel pump, fuel filter, FPDM, Inertia switch
Fuel delivery= fuel injector, fuel injector o rings, fuel rail

If u were runnin rich on both banks instead of one then probably fuel supply system.
If u were runnin rich on one bank then probably fuel delivery system...

 

Did you ever solve this? My 2006 is showing the same issue right now.

 

i dont know what to tell you here I've never had this issue