2G car is leaning out

[DiamondStar90]

Okay guys here's a quick run down of the car and you can tell me what you think.

95 TSi AWD, built 2.0 engine, 274 cams, HTA 76 turbo @ 28psi, 2150 high z blue max, Walbro 450lph, E85.

Just fixed the issue on fuel pump o-ring, I believe WAS KINKED and now have thee AFPR set at 43psi. The car ran great before as is tuned but I noticed as I get into boost it starts to lean out now to 16 AFR's so I stopped.

ANY SUGGESTIONS?

 

[StrokerMax]

Did the issue start right after you made the O-ring repair? Have you recently check for boost leaks?

 

[DiamondStar90]

IT GOES TO 26-28 PSI ns yes it's after the o-ring fix cause before I messed with o-ring it would only go to 25 psi on FP regulator.

 

[StrokerMax]

Okay. I'm not a pro on this but maybe with the two of us we can figure it out.

Just want to make sure you correctly set your baseline fuel pressure on your regulator. Make sure the car is up to temp and the vacuum line is pulled and capped (either with a cap or just your thumb)regulator. http://www.dsmtuners.com/threads/how-to-set-fuel-pressure-with-an-afpr.402582/

I would think there are a number of things that could cause this

1) Its related to fuel pressure, fuel vacuum, or an obstruction in your fuel system somewhere. Might want to make sure your fuel filter isn't clogged. Less likely could be a problem with your fuel pump or a clogged injector. What fuel pump are you running? Are you pulling any codes? Maybe Something could have gotten messed up when you were in the tank fixing the O-ring.

2) Could be a problem with your tune. Might be worth pulling a data log to see if anything looks out of the norm. I wonder if your car is in open loop or closed loop when the problem occurs. Could also be a problem with a sensor such as a bad front O2.

3) A boost or exhaust leak which is causing a bad reading in your wideband and front O2.

I still think its related to what I mentioned in number 1 since the problem happened after you repaired your o-ring.

 

[mercaholik]

If you can't get your fuel pressure higher than 25psi.(originally now you have 43.5) my guess is fuel is leaking from high pressure line inside the tank. Or maybe some type of restriction in one of the fuel filters. Have you checked the fp regulator?