New Fuel Pump Relay...still no go

[uncletammy]

My 1981 320i will drive fine when its cold but it will die and refuse to start again when it gets hot. After it cools off it starts fine though. I concluded that it was the fuel pump relay based on other peoples advice. I replaced the fuel pump relay but It is still doing the same thing.

In the fuse box, there is one tall black relay and below it are 4 or five shorter black relays. Is the fuel pump relay the tall one...because thats the one that they gave me to replace. I just want to make sure I got the right part. Could the problem be in the other, shorter relays? How likely is it that its the fuel pump? Do I have to buy a new one or could I adapt one of those generic ones to fit it as long as its putting out the right volume? How many cfm do the fuel pumps on an 81 320i put out?

Does anyone have a fuel pump that will work that they might be willing to get rid of? I was looking for used ones and I found one for a 79 320i that supposedly works for $40. Can anyone confirm this? What year fuel pumps are going to be compatable? As you can probably tell, im pretty much convinced that its the fuel pump. If anyone has any other ideas, I would love to hear them.

I had an earlier thread describing my problem here:
http://forums.bimmerforums.com/forum...d.php?t=363044

Thanks so much for the help

[Monk183]

I have a pump from an 1980 320 i if your intrested.

[uncletammy]

Will it fit my 81? Does it sound to you like the problem is the fuel pump?

[Monk183]

it sounds like a sensor or vapor lock but check all of your grounds i remember reading about this problem somewhere..

[uncletammy]

What kind of sensor? 02 sensor? Grounds to the fuel pump? Im totally new to bimmers so I have no idea what goes wrong with them. Thanks.