[Dokrai]

Hey guys!

picked up an X5 35d for daily/winter driving, got a couple codes for def fluid level sensors and just bit the bullet did the delete. While doing the delete I got a tune and started having some issues shortly after.

The first issue is long crank. This has been a bit intermittent, I suspected air in the system, did a bleed with cracked injectors. Sometimes the car starts up on the first rotation, sometimes it takes a good 2-3seconds.

The second issue is loss of fuel pressure under load. From the log I took it looks like the moment it approaches that 20-21kpsi the difference between commanded and actual is 2-3k and the car goes into limp mode.
Log attached: https://datazap.me/u/paulmazur/rail-...ta=2-3-5-6-7-8

Things I have done so far!
*Replaced the regulators on back on HPFP and rail
*Checked injector flow back and replaced 2 injectors due to excessive flowback
*Replaced Fuel Filter

I'm leaning towards the HPFP as the LPFP pressure is fine, and the only other thing in the fuel system is the HPFP and 4 injectors which tested fine. Any help, or a way I can make sure it is the HPFP?

[barf]

Issues started right after tune or was there a buffer?
Could be tune related.
Check fuel pressure during cranking if it comes up fast enough. Logs would be better if it was under max load.
If backflows are OK then problems with rail pressure control valve are likely (at the end of rail).
I highly doubt its the fuel pump but of course its possible. R70 is a great pump.

[lnxguy]

Who's the tuner?

[335dlci]

R70 are good but they sometimes fail.

[Dokrai]

The control valves have both been replaced. End of rail and back of HPFP. There was a buffer between when the tune was installed and when issues started. The tune that was put on was the malone 2.9.