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My 06 325CI E46 will not start. That's because there is no fuel pressure which I verified. I checked the fuse it's good. I checked the fuel pump relay and it is good. I also swaped it out for the horn relay and everything is the same. I have 12 volts going to the relay. When I check at the fuel pump I only have 4 volts. I don't get it! :mad: I also checked the level sensor and it only has 4 volts also. I do not know what else to check. If anyone has any ideas I could sure use some help.
 

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catso
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My 06 325CI E46 will not start. That's because there is no fuel pressure which I verified. I checked the fuse it's good. I checked the fuel pump relay and it is good. I also swaped it out for the horn relay and everything is the same. I have 12 volts going to the relay. When I check at the fuel pump I only have 4 volts. I don't get it! :mad: I also checked the level sensor and it only has 4 volts also. I do not know what else to check. If anyone has any ideas I could sure use some help.
Battery issue or battery cables, connections, junction point? :dunno: I'd check these and clean them up and see what you get. If it's the original battery, you're due. Heat kills batteries.
 

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Discussion Starter · #3 ·
Battery is new and cables are good. I have 12 volts to the relay I just don't know if there is something between the relay and the pump.
 

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...I just don't know if there is something between the relay and the pump.
Yes, I believe it is called "a wire".

:p

Given the way the relay is wired (see pic), you could try measuring the resistance between its output terminal (in the socket, #87) and the corresponding terminal in the pump connector.

Either that, or the ground lead to the pump is bad. This may be the case; recall all the "my taillights are bad" threads, all caused by bad grounding, so this is a not-uncommon problem.
 

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Living Life At The Beach
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run a temporary wire from the relay to the pump. if it now works, you have a problem in your orig wire tht you have to track down, or bypass
 

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So what happened? I know it's 4 years later but now I'm having the same problem. Only 5 volts to the fuel pump. I measured the voltage across the pins and it's just under 5 volts. I used a ground on the body and got the exact same voltage. I swapped out the relay with no change. Still <5V. I can't get to the back of where the relay plugs in to check the output voltage of the relay. How do I get behind there to check? I suspect the power wire has a bad spot but I can't run a bypass to check it until I can get behind the relay plug. I checked the voltage at the fuse and it's 12V. I'm pretty sure that the fuse comes after the relay, so I probably have a bad hot (12V) wire between the fuse panel and the fuel pump. Any confirmation? I'll try to run a bypass tomorrow and see what happens.

Any ideas would be appreciated.
 

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+1 on ahull info

Sounds like you might have a bad fuel pump. Classic
Check your fuel pressure at the fuel rail. If weak, replace your pump.
 

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I believe you're right. I just put 12V straight to the pump with NO JOY. Not a whir or a click. BAV Auto, here I come! I'll post if the new pump solves my problem.
Thank you!
 

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Keeping it surreal
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I believe you're right. I just put 12V straight to the pump with NO JOY. Not a whir or a click. BAV Auto, here I come! I'll post if the new pump solves my problem.
Thank you!
Also, for future reference, Check the OP`s join date, and post count. Like this thread....the guy made 5 posts 4 years ago, and was never heard from since....quite common.
 
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