fuel pressure question

[jfoj]

Thanks for updating the thread, too bad the thread had to take the direction it did.

BMW uses different pumps across some of the chassis, some are Siemens/VDO, others are Pierburg. From the E46 chassis, the pumps are Siemens/VDO except for maybe the M3, and based on history, EVERY E46 should have a replacement fuel pump by now if you want a reliable vehicle.

Pretty much hold true for the E53 even if it may run a Pierburg pump, which it may as the E53 is a cousin of the E39.

For the pump price and the ease of replacement, it makes no sense to brag about how old or how many miles the fuel pump may have. I prefer to proactively replace electric fuel pumps by the cars 8-10th birthday because I do not like walking when I should be driving.

I think everyone will see that the E53 pumps will soon start failing in large numbers if they have not already started. The no starts tend to begin in the Winter months with the cold temps and after the vehicle has sat over night for a good cold soak. But before the pumps cause no starts, they get soft/weak and cause driveability problems and will cause the sucking jet/siphon pump to not work properly and the vehicle will also "run out of fuel" with the tank displaying 1/4 full.

I am sure everyone will have their own opinion and make up their own mind, but I highly recommend replacing the fuel pump as a preventative measure.

[X53Jay4.8is]

Originally Posted by jfoj

Thanks for updating the thread, too bad the thread had to take the direction it did.

BMW uses different pumps across some of the chassis, some are Siemens/VDO, others are Pierburg. From the E46 chassis, the pumps are Siemens/VDO except for maybe the M3, and based on history, EVERY E46 should have a replacement fuel pump by now if you want a reliable vehicle.

Pretty much hold true for the E53 even if it may run a Pierburg pump, which it may as the E53 is a cousin of the E39.

For the pump price and the ease of replacement, it makes no sense to brag about how old or how many miles the fuel pump may have. I prefer to proactively replace electric fuel pumps by the cars 8-10th birthday because I do not like walking when I should be driving.

I think everyone will see that the E53 pumps will soon start failing in large numbers if they have not already started. The no starts tend to begin in the Winter months with the cold temps and after the vehicle has sat over night for a good cold soak. But before the pumps cause no starts, they get soft/weak and cause driveability problems and will cause the sucking jet/siphon pump to not work properly and the vehicle will also "run out of fuel" with the tank displaying 1/4 full.

I am sure everyone will have their own opinion and make up their own mind, but I highly recommend replacing the fuel pump as a preventative measure.

This is sound advice.

[80stech]

Geeze I just changed the fuel filter and had to figured this all out on the weekend. I wish I had seen this post about the M54 not making use of manifold vacuum on the fuel pressure reg. I first assumed that someone had previuosly connected the hose wrong since mine had body work done on that side! I couldn't understand it because it looked factory but didn't make sense. I guess they didn't want to vent the regulator underneath the car and also make use of the same filter fittings/lines. Good to know for sure!