Had my first ever breakdown in any car that I've owned in the last 10 years and was a bit, erhmm, surprised, to say the least.....Well, it was kind of my fault, so can't really blame anyone else. I mean, how long do you expect a fuel pump to work on a 25 year old car and god knows, if it has ever been changed?
My only excuse is that this just happened out of nowhere, really....If I would've had any kind of obvious symptoms recently, then I would've known what to expect, but it just randomly died. Have to admit, the car sputtered and cut out on me in traffic few months ago, but then it started right back up and has been fine ever since, so I didn't really think much about that incident....Anyway, lesson learned. Here's my taxi below:
Long story short, I'm a bit of an idiot for completely forgetting about the fact that after all the work that I've done on the car, I've missed the fuel pump and should've replaced it loooooong time ago to avoid this silly situation. Luckily, it was a nice sunny afternoon and I was in my local area driving around 20 mph when the car all of a sudden lost power, stopped reacting to the accelerator pedal and gradually came to a halt on a residential road. Tried starting it again, but it would just crank without firing up. I managed to push it away from the road and park it in a bay until a colleague of mine recovered me to a friend's house the next day.
A bit of an inconvenience, but I appreciate that it could've been a lot worse, such as cutting out at 70 mph in the outside lane of a motorway at 3am in the morning, on the way to the airport! Touch wood, I always look after my cars well and such things don't normally happen with me, so this incident definitely took me by surprise.
IMPORTANT: It's recommended to have 1/4 full tank of fuel or even less, if possible, when replacing the fuel pump, as it will make a lot easier removing the pump since you'll have a clear view of how it's fitted in the tank.
The fuel pump on the E34 is located under the carpet, in the boot and there's a black cover held by 5 screws that you have to remove to access the pump.
Once you've removed this cover, you'll see the top of the fuel pump assembly, which has a plug connected to it and 2 fuel hoses, as below:
To remove the plug, you need to slide the metal bracket away from the connector while simultaneously pulling the plug outwards. As for the fuel hoses, unless you have the special tool for removing/locking those fuel hose clamps, it's advisable to have some replacement BMW jubilee clips/hose clamps (part number: 07129952104) before you start undoing those. Also have some cloths/towels ready, as some fuel will spill out and you don't want to make a mess.
Make sure to clean up all the dust and dirt around the assembly, because once you've removed the cap, then it could all go into the fuel tank, which obviously you want to avoid.
You'll have to gently tap the black cap with a flat screwdriver and a hammer in an anti-clockwise direction, because there's no way of undoing it by hand. Once you have unscrewed it, you'll have to move the fuel sender part of the assembly out of the way (the white part) and reach into the fuel tank with your hand to unclip the pump assembly from its bracket located in the tank.
It is a bit fiddly, but this is the reason why you should have a minimum amount of fuel in the tank, because otherwise you won't be able to see how the pump is held in place or how to remove it. There are basically 2 tabs on the assembly that you push inwards and then pull the pump up from the bracket. See the photos below of the whole assembly removed to get a better idea.
Notice those tabs on each side of the fuel pump assembly, which is what you squeeze inwards from the top to release the pump from its bracket in the tank. Also see how all the clips used around on the assembly are special hose clamps. There's no need to replace these, as long as you have the right tool for unlocking/securing them.
Remember how everything is connected, so depending on which replacement fuel pump you get, you'll know how to correctly re-connect it all back together. The thinner/smaller stud on the pump is Positive (+) and the larger one is Negative (-).
You won't have to worry about replacing the fuel pump filter separately, as usually they come together with replacement fuel pumps, so that's one less thing to worry about. However, if you don't have it, then make sure to get a new one, as it wouldn't make sense to go through all this work and re-use an old filthy filter.
Depending on what manufacturer you go for when buying your new fuel pump, you may have to do a bit of extra work and it won't always be a straight swap-over. For example, the pump that was fitted on my car was made by Bosch and in the past, you could simply buy just the pump itself, without any other accessories, and replace it hassle-free. You would have to separate it from the inner housing, but that's about it - see the pics below.
Checking the above part number, you can no longer buy this exact Bosch fuel pump, because it has been superseded by a newer unit, which comes complete with a plug on top and a wiring kit, meaning you'll have to mess around with the existing wiring of the pump assembly to crimp in new pins, so then you can push them into the new connector and plug it into the pump......Not the best scenario, but if I was to go with a Bosch replacement, then it would have to be part number 0580314123, as per the photo below:
As you can see, it is supplied as a complete assembly with the filter and the inner/outer housing, along with 2 pins and a connector. Like I said earlier, the downside to this is that you'll have to modify the wiring, which I didn't want to do, so I decided to go for an alternative make. For your info, you can get an equivalent pump to the original Bosch one that was fitted on my car, i.e. with the studs on the top, but then it would be an inferior quality make and probably wouldn't last long.
Luckily, another OEM alternative to Bosch is a Pierburg pump (part number: 7.21913.50.0) , which actually comes with studs on top, meaning it's just plug and play without any need to modify anything. It was readily available from EuroCarParts, so I got it straightaway and here's how it looks like:
When I opened the box, the part number on the actual pump was different from what was on the label, but after checking the part numbers in the Pierburg's parts catalogue, everything matched fine - for your info, 7.21833.51 is an old number (stamped on the pump) and has been replaced by 7.21913.50.0 (on the box).
After finally doing all the research and purchasing the right fuel pump, it was just a matter of putting everything back together and starting the car. You will have to re-use the outer part of the pump bracket, which fits over the new inner bracket of the replacement pump. There's only one right way of fitting it, so you can't really get it wrong - just pay attention to how it's installed, when you are removing it from the old pump.
Then you'll have to re-connect the wires to their studs (positive/negative) and secure them with washers/nuts. One hose goes on the pump that supplies the fuel into the engine and the other one connects to the outer bracket, which is the return fuel line. Again, pay attention not to confuse them and replace the hose clamps, as required. All done, ready to be fitted:
The installation is the reverse of removal, so make sure that the black part of the pump assembly properly clicks into place in the fuel tank, then carefully put the fuel sender back in as well and install the black cap with a few light taps of a flat screwdriver + hammer. Secure the fuel hoses, re-connect the plug and you are done!
Started the car, it ran perfectly fine and I haven't had any problems since. Still can't believe that this actually happened to me, considering all the things that I've taken care of, but like I mentioned earlier, totally forgot about the fuel pump. Funny enough, I did replace it as a precaution on my previous car, an E30, but for some reason it slipped past me on the E34. Well, what can you do?
Have to say that I've noticed a significant difference of how the car pulls away and gathers speed, so it seems like the old pump did work, but it was definitely weak. It's now a lot more responsive and smoother and there's no hesitation in the lower revs. A happy ending overall.
Apart from this, not much happened lately. Still haven't fitted the replacement second-hand rear window regulators that I bought back in August, so that most likely will be the next job, but otherwise if anything else comes up, you'll be first to know.
Thanks for reading.