Fuel filter and pump installed won't start
 

I am sure this is a repetitive thread but please indulge me. My 2005 R53 had computer issues so I installed a reprogrammed DME from RPM. It worked and the car started and ran but went into limp mode when warmed up. I am less than a novice mechanic so I decided to take it to a local shop but thought I would change the fuel filter first, as the car had been sitting at the previous owner's house for 3 years. After I installed the fuel filter the Mini would not start. Not stumble, nothing. Again, it ran before I installed the new filter. I had the car towed to the shop and asked them to get it running and asked them to take out the filter and refit it as they would normally. It would not start and they insisted the pump was bad as there was no pressure at the fuel rail. I could hear the pump run when I put the key in, and I knew the pump had been replaced before the car was sitting, so I had the car towed home. I bought a certified "working" used pump from Almag for a good price, just to check their diagnosis. After installation, nothing. So, my questions are 1. anything I should look for on the filter cannister? 2. is there something about filter installation that is special? 3. is there something I should look for on pump installation? 4. how about hoses, broken or blocked? 5. any other thoughts. I am most appreciative of any and all help here. I live near Upland CA and there are no Mini shops around here that will touch the car or which I trust, but I am open to any suggestions. Thanks!

O ring on filter lid

^^ 2 check o-ring. Also, pull new filer and make sure old filter came out completely. There is a paper element and a black plastic disc on either end of the filter. The plastic will often separate from the paper filter and with the fuel all black in color it's hard to tell. make sure everything is out. Otherwise, no seal and no start.

It's also possible that you simply don't have the filter housing top completely locked into place. Happened to me the first time I changed my filter. Wouldn't start and I retightened the top three times before it finally kicked off. It's a closed system so if it's not perfectly sealed it will not start.

Had the same Issue, it ended up being the large skinny o ring on filter top that got cut while installing, rub some oil on them To help. I bought extras for next time.