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Discussion Starter #1
If somebody could just reinforce what I'm thinking. Yesterday I was on a 2 hour road trip down the Mass Pike, cruising at about 80mph I noticed while driving a few blips like it got stuck for fuel. I started to pull into the rest stop idle came down and the car stalled. I let it sit for a few started up then just died out. I started it back up kept the RPM's up and got back on the highway and got home ok. Still dies at idle.

I think its the filter, the pump is buzzing fine. What do you guys think ?? Thank you..
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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You can change the filter, but buzzing doesn't equal pumping. Test the pressure with a gauge at the fuel rail by briefly starting the engine. It should show in the mid 30s psi. Remove and plug the vacuum line from the fuel pressure regulator and start the engine again. It should show upper 30s to mid 40s psi. If it won't make 30 psi at low rpm, suspect the pump is dying. If it doesn't make any difference/won't make upper 30s/lower 40s with the vacuum line disconnected, the fuel pressure regulator is bad.

Dying at idle usually means a vacuum leak, but blips at speed is usually the fuel pump hiccuping.

What year/model is your E30?
 

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Discussion Starter #4
just quick question..How do I know if its the tank or the inline pump that's bad ?? I believe this car has two.
 

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D'oh, You Kids!
1984 633CSi, 1985 635CSi, 1985 325e, 1987 325is, 1993 325is, 1995 318is, 1995 M3, 2003 F150
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29,546 Posts
That's why I asked what year/model your car is. 84 to mid- 88 had two pumps, a low pressure/high volume in-tank pump, and a high pressure/low volume external pump. 89-93 had one in-tank high pressure pump.
 

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Discussion Starter #6
Ohh, ok sorry didn't see that,, I have a 89 325IS..I'm going to go ahead and do a filter and pump change. Hope that take care of it. Thank you for the advice.
 

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Nick's Toys
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I'm going to go ahead and do a filter and pump change. Hope that take care of it
One word of advice from somebody in the automotive field.
It is a lot cheaper testing components instead of just replacing them.
 
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