CPS failure question
Thread Starter
Newbie
Joined: Jun 2012
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06 c230 sport
CPS failure question
Hey guys
I've got a 2006 c230 with a no start. I've been reading around this forum and I see that crank/cam position failures are common. With what little day light I had left this afternoon I checked for spark and fuel. I confirmed I have spark but the fuel pump is definitely not running.
My question is, if the CPS fails, would you get no fuel pressure and no spark or does the cps not have anything to do with spark?
Also could anyone tell me what wires are power and ground off the fuel pump harness? Thanks.
I've got a 2006 c230 with a no start. I've been reading around this forum and I see that crank/cam position failures are common. With what little day light I had left this afternoon I checked for spark and fuel. I confirmed I have spark but the fuel pump is definitely not running.
My question is, if the CPS fails, would you get no fuel pressure and no spark or does the cps not have anything to do with spark?
Also could anyone tell me what wires are power and ground off the fuel pump harness? Thanks.
Super Moderator
Joined: Dec 2006
Posts: 2,403
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
No, bad CPS would not cause no fuel pressure. You need to hook up a fuel pressure gauge to the fuel rail and check that you have pressure (3.7 - 4.2 bar) WHILE CRANKING.
Thread Starter
Newbie
Joined: Jun 2012
Posts: 11
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06 c230 sport
unfortunately I don't have a fuel pressure tester. The way I checked it was removing the valve on the fuel rail and hooked rubber tubing to it and let it drain into a bucket. I can tell u the fuel pressure while cranking is very much zero. I guess if the cps failure wouldnt cause the pump to not run then I'll start by checking the pump and trace backwards.
Super Member
Joined: May 2009
Posts: 904
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From: Toronto, Ontario, Canada, eh!
2003 C230 Sports Coupe, Paprika Metallic Red, Auto, Pano, Leather
Removing valve??? Its like a air valve for tire,... just push it and gas should come out. Even if the car hasn't been driven for a week it should still have some gas pressure in there,....
What is your mileage?
Lift rear seats, do you hear fuel pump working when cranking?
It could also be clogged fuel filter,....
What is your mileage?
Lift rear seats, do you hear fuel pump working when cranking?
It could also be clogged fuel filter,....
Thread Starter
Newbie
Joined: Jun 2012
Posts: 11
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06 c230 sport
Yea it's a schrader valve you can just unscrew it if you dont want to get gas all over your engine while you crank it (which is not a good idea). I don't hear the pump running, doesnt feel like its running either. I don't think the fuel filter is blocked but I'll check it anyway. The fuse and relay are working from my basic tests. Only thing I need to check the wiring harness is the wiring diagram if anyone wouldn't mind posting it up.
