# P2177: Fuel Trim, Bank 1 too lean from idle



## jhines_06gli (Feb 3, 2006)

Alright, I've had many of the P2188 faults for too rich with fuel trims dipping past -18%. But have had VERY FEW too lean off idle, as our cars go rich off idle since they are turbo. But I have been fighting this friend's car for a few months off and on now. 
2006 GTI 2.0T FSI
REVO II+, KMD HPFP, Neuspeed CAI, EuroJet VTA catchcan, A3 throttle body pipe. 
Basically, all this cam eabout all the sudden right after H20i '09. Installed EJ catchcan just before H20i and drove there no issue. Got back and a few weeks later installed A3 throttle pipe to delete noise pipe. About a week later got the CEL for lean off idle. Fuel trims were at -1.7%STFT and 22.8%LTFT. Replaced the MAF sensor as that was first instinct. No change, the code came back 2 days later. So I pulled the intake and cleaned all valves, replaced the injectors and did a SeaFoam treatment. Shipped car and came back on a few days later. The fuel trims dropped to about 18%, but still too high and fluctuate to 21-22%. 
Basically, the only time I have seen this was the first-run production of the BSH TrueSeal intake systems, the MAF placement was not far enough from turbo inlet and you had a pressure issue there. But the Neuspeed has never given myself or the other 8 or so cars in our club any issues. And had another P2177 pop up last week on a friend's cvar that runs the EVOMs intake, but both cars have had these intakes installed from almost day one and well over a year!
Any input/experience with this is greatly appreciated and I'll keep it updated with what I find/try.
-J. Hines


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## MK4 Getta (Jun 2, 2006)

*Re: P2177: Fuel Trim, Bank 1 too lean from idle (jhines_06gli)*

I have a system too lean code too. i brought my car in for the coils to be replaced under warranty. as soon as i left, the MIL came back on. When I got home I ran the codes and they went from a misfire to a system too lean and a high idle.....i just got a call from the dealer and they said it is caused by "high revving" and that I need a new fuel pump and camshaft and it is $2200......


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## jhines_06gli (Feb 3, 2006)

*Re: P2177: Fuel Trim, Bank 1 too lean from idle (MK4 Getta)*

lean faults are not HPFP related. There are completely different codes for cam issues. And not caused by high revving cause I drove the car down the street at 45 MPH and watched fuel trims go from 0% when fault reset to 14% in under a mile!!
-J. Hines


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## TAIVWAUDITECH (Dec 23, 2006)

*Re: P2177: Fuel Trim, Bank 1 too lean from idle (jhines_06gli)*

Have had this code with a failing KMD pump.At low rpm the pump pressure is too low and code went away after replacing the pump.
What is odd,is I have also had rich codes from a failing pump as well.
With these cars I have replaced (on different cars) the low pressure fuel sensors,in tank pump modules,injectors,pcv's,DV's it is just ridiculous.
With the 1.8T's people were complaining about the stock DV's and coil packs,oil sludge.......
WIth the 2.0T they jsut gave us a whole plethora of different issues to contend with










_Modified by TAIVWAUDITECH at 10:31 AM 1-14-2010_


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## jhines_06gli (Feb 3, 2006)

*Re: P2177: Fuel Trim, Bank 1 too lean from idle (TAIVWAUDITECH)*

yea......seen the failing pumps cause code P2188 for too rich due to fuel in oil, but not for lean faults. I have several HPFPs and may try to swap one out to see if that changes it, but it's only 6k miles old! KMD guts were installed into brand new, off-the-shelf HPFP. But injectors, PCV, DV......all that is either new or aftermarket. 
-J. Hines


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## MK4 Getta (Jun 2, 2006)

*Re: P2177: Fuel Trim, Bank 1 too lean from idle (jhines_06gli)*

So, what should I do? The stealership told me to replace the pump and cam....and wanted 2500 to do so. i have done a smoke test and everything for a vacuum leak and there is nothing coming out and the engine is holding pressure...
im sorry, i wont highjack your thread, i will start my own!


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## jhines_06gli (Feb 3, 2006)

*Re: P2177: Fuel Trim, Bank 1 too lean from idle (MK4 Getta)*


_Quote, originally posted by *MK4 Getta* »_
im sorry, i wont highjack your thread, i will start my own!

PM me the exact code you have.......also any VagCom data if you have it
-J. Hines
Wish you were local, we are friendly to mods







At least me and 2 other techs are


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