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mwdean
02-04-2010, 11:38 PM
this is my first post on the forum, i'm a 30 year dodge tech & just became sprinter tech by default 2 months ago. benn to chrysler tech school on sprinters, but only newer v6 models are used. i am attempting to repair a 2003 612 with an electrical problem in the fuel inj area. it turns low fuel press lamp on & goes lhm. the tech that i replaced has already replaced lift pump, hi press pump, several fuel filters, hi press fuel sensor, fuel solenoid, egr valve, maf, intank module, fuel hoses from tank & filter to fuel rail. he also replaced all injectors. when none of this fixed the prob he replaced lift pump & filter again. he got himself fired over this truck and now i've inheirted it. the active codes are p0100 maf sensor,p2006 fuel press, p2007 fuel delivery, I have the correct fuel pressure gauge & drb 3 hooked up the fuel pressure is fine with 35psi at idle, & 50 psi at 60 mph the drb also reads this same psi until the warning lamp comes on. the mechanical gauge still reads ok but the low press reading on drb drops to zero so it is not an actual press problem but electical whwn this happens the maf reading on drb also zeroes the only common denominator seems to be the ecm, but as you can imagine the owner is tired of throwing money at this truck. does anyone know of a ground or wiring problem that would tie the maf & lo press sensor together

sikwan
02-05-2010, 12:56 AM
Do check the wiring for routing issues. It seems to be common with Sprinters.

A couple issues with a later model Sprinter...

Routing around the manifold.
http://sprinter-source.com/forum/attachment.php?attachmentid=8119&d=1213292693

Wire chaffing near ECU (mine clears)...
http://sprinter-source.com/forum/attachment.php?attachmentid=4048&d=1191252999



Since the last mechanic went through a replacement spree, I wonder if he/she has added another problem to the problem. :frown:

abittenbinder
02-05-2010, 04:02 AM
the active codes are p0100 maf sensor,p2006 fuel press, p2007 fuel delivery, I have the correct fuel pressure gauge & drb 3 hooked up the fuel pressure is fine with 35psi at idle, & 50 psi at 60 mph the drb also reads this same psi until the warning lamp comes on. the mechanical gauge still reads ok but the low press reading on drb drops to zero so it is not an actual press problem but electical whwn this happens the maf reading on drb also zeroes the only common denominator seems to be the ecm,

does anyone know of a ground or wiring problem that would tie the maf & lo press sensor together

The 0100 MAF code, as you well know, is a low supply V code. The MAF sensor has both 12V and 5V supply from the ECM as well as a sensor ground from the ECM.

The low pressure fuel feed pump pressure sensor has a 5V supply from the ECM as well as a ground signal.

The ECM regulated 5V supply to the Low fuel pressure sensor is not in the same supply group as the MAF 5V supply. The MAF is grouped with the accelerator pedal sensors and the oil sensor.

The low fuel pressure 5V supply is grouped with the boost pressure sensor and the rail pressure sensor.

The MAF sensor's 12V supply is grouped with 4 other devices, none of which you are experiencing difficulties with.

I would look at engine wiring harness geographic commonality issues before condemning the ECM. Doktor A