[matreyia]

Precision Raceworks
Stage 2 Low Pressure Fuel Pump

BACKGROUND:
2009 335I E93
Body 98K miles
Engine and turbos 15K miles
Automatic

UPGRADES:
MMP 2 inch Inlet and Outlet kits
VRSF Down Pipes
DINAN - Intercooler, oil cooler, carbon cold air intake
BMW Performance Exhaust
RB PCV Valve

Tuning: Attempting to tune with Wedge Performance tune from Ken Atkinson.

While attempting to tune with Ken, I encountered problems of choking, stuttering, shaking, misfires, shuddering, fluttering and confused shifting from the transmission. Ken looked at the logs and determined it was the HPFP. I tried a series of processes to rule out anything else.

1. Reset adaptations - that helped the misfires a little bit, stuttering too.
2. Reset Transmission adaptations - (MUST PERFORM ADAPTATION PROCESS AFTER) this process almost eliminated the shifting issues. Be warned, you will need 75 miles of uninterrupted road to do adaptation programming after resetting. Or use a local dyno machine.
3. Replaced stock LPFP with Precision Raceworks Stage 2 LPFP.
4. Replaced HPFP.
5. Replaced all manifold and throttle body gaskets
6. Cleaned throttle body.

Results after Stage 2 LPFP install: The car ran completely stable, smooth, and response was substantially better than before install. Logs showed average consistent 85 psi and the lowest point never went below 60 psi. Stock lowest was below 50 psi. and highest was 72-ish psi.

The car felt like a new car after the Stage 2 install. I highly recommend the upgrade especially if trying to tune. This fixed 80% of the problems for me. The other 18% was the HPFP and minor technical adaptation settings.

Installation was blind for me since the instructions were not available yet. So Robert at Precision Raceworks walked me through the install via text and phone. Was scary, but looking back, wasn’t that bad. Would be very fast next time… probably an hour if I had to do it again.

There should be a good instruction manual available by the time you read this so this should not be an issue.

AFTER HPFP INSTALL.

So after the LPFP was installed and tested, I did the HPFP and that completed the solution to my problems. Car now runs perfectly and no issues with hesitation or stuttering…amazing what fuel pumps can do if they work.

I highly recommend the PR Stage 2 pump. The design is modular and IMO better than the others available…mainly because you don’t have to worry about the black stock plastic framing… you simply cut things out and discard and PR gives you a metal framing that is MUCH better to work with. Believe me, if you don’t have that metal frame…you have a VERY HIGH RISK of breaking the stock plastic framing and then you have to buy a brand new LPFP and risk it all over again.

That is my 2¢. Enjoy.

[BeastMode335i]

Thanks for ur review...