No power to the fuel pump

joe_keefer · Post by **joe_keefer** » Sun Dec 12, 2010 2:57 pm

hi everyone,

i have another hopefuly simple problem. my 79 528i has no power to the fuel pump. there is power at the fuse. power at parts of the combo relay, although i`m not sure when power should be where. i did read the FAQ about it. but at this point my brain is mush. i`m having the exact same problem with my88 range rover. so i`m a bit wigged out right now. if i could afford to just replace all of the fuel inj parts i would. can somebody talk me through this? thanks in advance.

Jeff Dennis · Post by **Jeff Dennis** » Sun Dec 12, 2010 8:13 pm

Joe,
Did you try to to prop open the flap in the Air Flow Meter and check for current at the fuel pump with the key on? If not try this first - remove the hose to the air cleaner and put something into the AFM to open the flap I use a screw driver.
Let us know the result.

joe_keefer · Post by **joe_keefer** » Sun Dec 12, 2010 9:50 pm

i hadn`t at the time of my post. i continued reading here and in my manual and saw that the flapper would activate the pump. i tried that but only to hear that it made the combo relay click. tomorrow i will do it again while under the rear to hear / test the pump. i tell you i`m tempted to just buy a new pump and combo relay. this car has sat for 5 years and was only run a few times in the first 1-2 years. i`d like to adj the AFM a touch richer either way. i will keep you posted.

thanks, joe

Mike W. · Post by **Mike W.** » Sun Dec 12, 2010 11:23 pm

joe_keefer wrote: i`d like to adj the AFM a touch richer either way. i will keep you posted.

thanks, joe

Be careful on that. I know it's popular in the E28 world, but I tried it on an '80 E24 one time and every couple of days it would go into a massive rich full puke mode. It would die or be undrivable and I could get it to run again by disconnecting the O2 sensor. But except when it did that it didn't run any different. And that was with a whole 2 clicks richer on the AFM.