Got my GT42R kit installed with new fuel lines, fittings, pre-filters, SARD fuel rail, SARD FRP, ID2000 injectors, twin Bosch 044 pumps and a fuel cell. I´m running twin -8 lines from the cell through the pumps to the rail ends. Running a single -8 return line from the middle of the rail to the FPR and back to the cell.

After running a while the car suddenly went lean and had to pull over. Waited for a minute and all was fine and could drive another few mins before running into the same problem again. Also noticed a change in pump noise when running lean.

Plugged in a pressure gauge and saw a dip in fuel pressure when running lean (from 30psi all the way down to around 15psi, sometimes just stuttering around 40psi). Also checked voltage at pumps and both showed 13.8-12.8V depending on how low the idle went from running out of fuel.

I noticed a scratching sound from the other pump and found out it was also noisier than the other and was running hotter than the other. Took out the fuse for that pump and ran with the other one and noticed the pressure was steady at idle (fuel would now partly run back through the other line against the pump). Took out the fuse from the "working" pump and ran the "broken" one and now the pressure would stutter.

Took the "broken" one out, found out there was some junk in the pre-filter, cleaned it and plugged it back. Now it would run at the same sound level as the other but still would have the scratching noise and noticed that the pressure stuttered at the same pace with the scratching noise.

Tested the "broken" pump with few buckets of water and the scratching noise was gone and the pump seemed sound. I still assumed the pump was broken, plugged the whole line and tried to run only the "working pump" with no other result than running lean again with lowered fuel pressure.

Any chance my FPR is already bad from new? Ideas?

Will check the other filter for junk tomorrow.

Video: http://www.youtube.com/watch?v=NQgmOzNpAfk

 

Other filter checked and it´s fine.

Also found out that when fuel pressure drops, there´s no to little fuel coming out of the return line so regulator should be fine. Also tested the pumps in a bucket with the regulator and they run 8bar just fine.

Only thing I can think of is that fuel starts cavitating at the outlet of the fuel cell, I propably need a surge tank.

 

make sure to check if there are any small leaks it can bleed the system and you can loose pressure check that also.

 

No leaks. I´m going with cavitation and will try to run a surge tank right under the fuel cell.

 

Have got suggestions from 2 sources to put the fuel filters on the pressure side, will try asap and report.

 

Any result and finding ? Because my car also happen this weird pressure

 

Do you have the same fuel delivery setup as the Op, eazlan?

 

Do you have the same fuel delivery setup as the Op, eazlan?