No Power to Fuel Pump- What is Going On??
Thread Starter
Member
Joined: Jan 2011
Posts: 100
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From: Scottsdale, AZ
C32, E93 M3
No Power to Fuel Pump- What is Going On??
My C32 suddenly wouldn't start one morning after a day of running about. All it does is crank over, but does not fire. So I first replaced the CPS thinking it was that, but it did nothing. I checked if there was pressure at the fuel rail and I found that there was none. So next I checked to see if there was power to the fuel sending unit (underneath the rear seats driver's side) and it's not receiving any power. Fuses are okay in the rear SAM. Relay is okay.
I'm at a loss. Please help. I am thinking it could be the ECU, but I have no idea how to test for this.
Any other suggestions would be much appreciated. Mods are 181 pulley and EC tune. Not sure if they could test to see if my ECU is fried.
I'm at a loss. Please help. I am thinking it could be the ECU, but I have no idea how to test for this.
Any other suggestions would be much appreciated. Mods are 181 pulley and EC tune. Not sure if they could test to see if my ECU is fried.
Thread Starter
Member
Joined: Jan 2011
Posts: 100
Likes: 0
From: Scottsdale, AZ
C32, E93 M3
ok, i just had someone help me crank it over while I tested for power. There is power to the fuel sender pump (rear seat driver's side) while cranking the car over.
So how do I tell if its the fuel sender pump or the actual main fuel pump that's the problem?
So how do I tell if its the fuel sender pump or the actual main fuel pump that's the problem?
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
There is only one fuel pump & that is built into the left or right fuel sender depending on model & market. If you have no rail pressure & your filter is not clogged then the pump is fried.
Good Luck!
Good Luck!
Thread Starter
Member
Joined: Jan 2011
Posts: 100
Likes: 0
From: Scottsdale, AZ
C32, E93 M3
I pulled the pump and tested it. It runs, but isn't super loud. Figured it'd be noisier. Maybe the problem is only a clogged filter. Seems strange that a filter could be that clogged that the car wouldn't even start.
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
The filter includes the fuel system pressure regulator if you have the external fuel filter. The pressure regulator might be faulty. We have had a number of bad ones lately. I don't know where the pressure regulator is with the newer in-tank filter.
