burned fuel pump power wire harness

[vincentwl]

2.2 NA 4WD 5MT
Yesterday I changed the old fuel pump with a walbro 255LPH, for two reasons, one is that I have this hard time starting occasionally, and I must have a cylinder that doesn't work well, engine is not smooth at idle, then I heard that subaru engines have this oil pressure problem will make one cylinder work poorly; while the other reason is that the walbro 255LPH is really cheap in China, like 20+ US dollars.

Good side is the car runs much more better than before, feeling more torque and smoother.

However, I can smell the gasoline in the car which I think it is due to the gasoline that drop out while changing the fuel pump is not gone yet. Hope nothing wrong with the fuel leak or something.

And, I have this recently fixed fuel gauge that is still not accurate, the max resistance of the two sender are 110, which makes the gauge will drop to empty with plenty of fuel in the tank. But it is OK. However I noticed that the gauge is dropping very fast after the fuel pump change. A full tank with 300km driving, the gauge is already reading empty. I can't stop wondering if the MPG is really that bad. I will go to the gas station and see exact how many fuel the car drank in this 300km. In the last tank, the fuel gauge went to empty and I added more than 50 liters in the tank, that will last 500km.

The most important one is that I can't start the car this morning. I can't hear the fuel pump working when the key turns to ON. Thus I know the fuel pump is not getting any power. After hours of locating the problem. I reconnected the harness under the rear seat, the fuel pump will work again thus the car can start. But, on the harness, this pin for positive fuel pump power line is burnt black, and it is very hot after starting the car for minutes. I am so worried about potential fire hazard. Thus I went to the factory, they hard wired the negative and positive power wire. They told me that some new cars will also have this problem, and it won't hurt. Now it is not that hot, it is more like "warm", I am not sure if it is OK. The rear seat seems flammable for me. Soooo worried that I won't put the screws of the rear seat back, for checking the wire every time I get on/off the car...

Any shared thoughts? Thank you!

[Legacy777]

I have not heard any comments regarding oil pressure causing issues on one cylinder. I have heard that the # 3 cylinder can lean out under high horsepower situations since it is at the end of the fuel piping. However, this won't be an issue for a non-turbo car.

Regarding smelling gasoline, I would suggest verifying that the hoses and fuel pump bracket are secure. If they are and you don't see any leaks, the smell could be from spilled fuel during changing the pump.

There are two fuel gauge senders for the AWD Legacies. I have had to replace both of mine. One sender is on the fuel pump bracket, and the other is a separate sender on the other side of the tank. Here are some pictures of the senders and pump bracket.

http://main.experiencetherave.com/subar ... fuelsender
http://main.experiencetherave.com/subar ... uelsender2

Regarding the electrical connector under the seat, this is a common failure point. The connectors get worn out, resistance increases and causes heat. The easiest way to fix it is to hard wire or put in a different connector. I put in a different connector. If the wiring is still getting warm, you may want to check the resistance of it to the fuel pump relay. Is it just warm around the new connection that was put in or is the whole wire warm?

Here are pics of my repair job.

http://main.experiencetherave.com/subar ... s/fuelsys/