C43 Fuel Pump
Member
Joined: Jun 2019
Posts: 79
Likes: 5
From: Iran
Glc43
m278 may not be an upgrade … the amg version of the m278, being the m157 engine platform, may use stronger pumps on something like the e63s for example. I wouldn’t expect e550 pumps to be an upgrade
regarding the Supra fuel pump, the video is very difficult to understand. Most high pressure pumps run off of two wires, usually a constant or switched ground, and the other wire being either constant, or switched 12v. Ordering a suitable pigtail and splicing the Supra pump into the engine harness should be the easy part
regarding the angle of the fuel fittings, I do not believe it is a requirement that hard steel lines are used for the fuel lines. Perhaps a hptfe or whatever, flexible/soft high pressure fuel line will allow enough flex in the line to utilize pumps with different angles of fittings
and if the Supra pump is close to fitting, in theory this could open up our options to aftermarket Supra pumps as well
regarding the fuel line fitting. Mercedes will probably use something like a 40 degree flared globeseal type fitting. A competent hydraulic shop, in theory, may be able to fabricate custom hard lines if needed
regarding the Supra fuel pump, the video is very difficult to understand. Most high pressure pumps run off of two wires, usually a constant or switched ground, and the other wire being either constant, or switched 12v. Ordering a suitable pigtail and splicing the Supra pump into the engine harness should be the easy part
regarding the angle of the fuel fittings, I do not believe it is a requirement that hard steel lines are used for the fuel lines. Perhaps a hptfe or whatever, flexible/soft high pressure fuel line will allow enough flex in the line to utilize pumps with different angles of fittings
and if the Supra pump is close to fitting, in theory this could open up our options to aftermarket Supra pumps as well
regarding the fuel line fitting. Mercedes will probably use something like a 40 degree flared globeseal type fitting. A competent hydraulic shop, in theory, may be able to fabricate custom hard lines if needed
have you done? Or consider doing it? Doable?
MBWorld Fanatic!
Joined: Jul 2012
Posts: 1,254
Likes: 171
2002 CL500 to CL55 conversion
I have learned more about how high pressure fuel pumps work in relation to the aftermarket/tuning world since that reply, and I would advise against changing out high pressure fuel pumps without having a suitable tune/fuel pump calibration file added to the car
MBWorld Fanatic!
Joined: Jul 2012
Posts: 1,254
Likes: 171
2002 CL500 to CL55 conversion
how did you install it then? You said you have it working? Did you just leave it disconnected?
The c63 tank is different than the c43 tank. I am thinking this may be an extra suction point on the c63 tank. if the c43 doesnt have it, its possible we wouldnt need it in our application.
The c63 tank is different than the c43 tank. I am thinking this may be an extra suction point on the c63 tank. if the c43 doesnt have it, its possible we wouldnt need it in our application.
i believe he left this port open most likely… and probably ran testing with full tank of gas. I believe a hose routed to pull fuel from bottom of tank would fix the issues with this.
I believe he will have had run into issues with WOT when driving with low fuel in the tank. He didn’t notice issues because his tank was full during findings
Newbie
Joined: Sep 2025
Posts: 3
Likes: 2
2018 Mercedes w205 c300 coupe
So did you just leave the 3rd hose off or did you block it off?
