BenzKraft

Hey guys,

I have a 2008 Mercedes E320 BT. Does anyone know how much pressure (psi range) the in-tank fuel pump should be pumping out if it is working properly? 60 psi? 65 psi? 75 psi? I know my pump is working and putting out 60 psi consistently (on start up and load test) but I think that might be too low and causing my P2633 DTC.

Cheers.

Anthony Porta

Any chance you have the full code from the canbus? What are you getting at the rail at idle and WOT?

kajtek1

Don't know factory spec, but this is just priming pump, so 60 psi sounds like plenty for purpose.
Would you have rail pressure as well?
The code sounds like bad connection, aka dirty plug at the pump btw.
Get good contact cleaner and wash all the pump connections with it.

BenzKraft

The only code from my iCarSoft MBII is 2633-000 plus a P0101 MAF code (pending). The rail pressure at idle fluctuates between 34500kpa (5000psi) to 35800kpa (5192psi) and at heavy (not wot) throttle is around 157800kpa (22886psi).

BenzKraft

Yeah I agree, 60psi should be adequate for priming but I wonder if it's too low out of spec and throwing the P2633. Rail pressure is about 5000psi at idle and 22886psi at heavy throttle. I checked the wiring to the in tank pump under drivers side seat and one wire was a little frayed so I cut and re-attached/soldered it and sprayed the connector with electrical cleaner. I cleared the codes and went for a test drive but that didn't solve the problem.