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Discussion Starter · #1 ·
Hello,

I replaced my fuel pump 1 year and 2 weeks ago with an OEM pump. Today the car would not start.

I can normally hear the pump start to whine when I turn the key, but the back seat is silent when I put it to position 1.

The multimeter is showing current at the end of the plug, I don't know enough to know how much current is supposed to be at that plug.

1. do you know what the multimeter should read when the key is turned to position 1 for the fuel pump plug? I have it set to 50 DC V and it reads like 10

2. is there any way to test the pump? I've only had this thing in a year and now it's not working.

Thank you for any advice,
 

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2005 330i manual transmission performance package
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When you say "OEM", what brand was it?
+1. A lot of people have replaced their fuel pumps preventively.
I guess they'd be interested to know these details.

I have a Siemens fuel pump sitting at home for more than two years. Initially I wanted to replace the original fuel pump of my previous E46, but decided to put that on hold after realizing the pumps on the early models don't fail as often as on the late ones. I'm about to put this pump in my current E46 within the next few weeks...
 

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OEM ///PLUS
2003 M3 6MT Slicktop
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well depending on your current reading i was going to say it could be your relay. but that doesn't seem like your issue. some of these pumps if not genuine BMW will still be of inferior quality. if you have a bad fuel filter that could also cause the pump to fail prematurely. bad "ethanol" gas can also be hard on the fuel pumps life depending on the area you live.

but i agree that your replacement pump should be lasting much longer than this. i had over 125K miles on two previous original pumps in my E46s and only changed them out for preventative maintenance. so another oe pump should do atleast half that on a bad build imho.
 

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Discussion Starter · #5 ·
Hi,

Thanks a lot for the replies.

I got it from oembimmerparts.com .. currently when I look on the site it is a "VDO Continential". That sounds familiar, but I dont have the box anymore to know for sure. I have the email receipt, and it just says
16146766942E46 BMW E46 3-Series Fuel Pump Assembly OEM
[Select Model:330i & 330ci 2001-2005]
[Enter the last 7 of your VIN:
Do you know what the current reading should be? I'll go out there right now and re-measure it.

Thanks,
 

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OEM ///PLUS
2003 M3 6MT Slicktop
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VDO is a very legit brand. but which factory it is made from now seems more the issue with some of these now a days.

i think it's either getting power or not. if getting power the relay is fine.

did you do the good old hitting the bottom gas tank trick? not that this is any fix per se but somethimes the actuator motor brushes stick.

i'm sure you'll get plenty of other help from members like jfol and others. GL
 

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10V is too low. Read voltage as you crank the engine.
 

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Discussion Starter · #8 ·
Gauge Measuring instrument Meter Tool Auto part
Without turning

Electronics Meter Gauge Measuring instrument Technology
Turning over


Sent from BimmerApp mobile app
 

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The resolution on that volt meter is not good for this purpose, but it does look like you are in the ballpark of 12 volts. Should be fine there.

Do you regularly run the car until the low fuel light comes on? If so you may be overheating your fuel pump causing premature failure.


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Discussion Starter · #10 ·
I read somewhere that anything under a quarter tank is bad for the fuel pump. I always fill it up Between half and quarter tank. I use Speedway premium gas. Just had dinner and then I was going to go try and hit the pump or tank like someone earlier suggested.


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It's over 12V, high enough. It looks like you have a short lived fuel pump on your hands. :(
 

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Discussion Starter · #12 ·
well I hit the pump and tank and no change...

I just saw they have a 2 year parts warranty where I bought it so I will fill out that form and see.

Thanks a lot for your feedback, guys.
 

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Discussion Starter · #13 ·
Well I replaced the pump today and it's still not working.

Before I have it towed to a dealer/repair shop, is there anything else I can check to try and diagnose this myself?

I know for sure that there is no noise coming from the pump. I can always hear the pump prime when I turn the key, and it's not doing that. We know that the plug is getting Volts, can I do anything else before I have someone else look at it?

Thank you again,
 

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Something does not seem correct here??

Usually with the key on, not cranking you will see about 5 Volts at the fuel pump connector (supervisory Voltage), then while cranking you should see 12 Volts.

There are 4 wires on the pump connector as I recall, 2 larger wires for the pump power and 2 smaller wires for the fuel gauge.

Are you sure you are reading the correct wires?

I would double check and also makes you are measuring both positive and negative at the fuel pump connector, you may have a bad ground, bad fuel pump relay or some other issue?
 

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Discussion Starter · #15 ·
Hi thanks for the reply.

I will to try to swap the horn and fuel pump relay next. If it was the relay, though there wouldn't be voltage at the plug right?

I'm going to double-check the plug wires to make sure I'm measuring it correctly. I'm not an electrician, I just put the multimeter leads in the plug until I got a reading. It did seem weird to me that the voltage wasn't different while cranking, but I don't know.
 

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OEM ///PLUS
2003 M3 6MT Slicktop
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I would like to clarify if the engine is "cranking over" and what is your definition by that?
not saying this is your problem (from the little I know about your symptoms) but your ignition switch ok? does your visor/vanity mirror lights act strange when keys in?
 

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Discussion Starter · #17 ·
Yes it 'cranks over' when I put the key all the way it tries to start.

The lights all come on bright, the radio works, etc. There does not seem to be lack of power either when I turn the key. Just no noise from the pump. I've not tried to spray starting fluid or anything because I can always hear the pump when I turn the key.

I watched this youtube vid and tried to get to those fuses, but I can't get the back thing off/out to check the middle fuse.

http://www.youtube.com/watch?v=QgBpu2iKjfw

If the problem was a relay, or if the problem was the fuse in that video, would there still be current to the plug? Is there a sensor or something that might be going bad?

I haven't double-checked the plug yet, I wasted my time trying to check that stupid fuse under the hood. It's really cold here so I came in to warm up for a bit.
 

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lol I knew it wasn't your pump. Plus I thought the pump comes on with position 2 not 1. Anyways, the reason may be the relay or the fuse under the hood. I too was stuck in a parking lot and had to have my car towed home. My fuel pump also wasn't coming on and I had recently changed it. Swapped relay and no change. Ended up being the fuse under the hood, the one in the middle.

I believe that one allows power to flow from the dme to the pump or something of that sort. Take it to the dealer and expect to get raped majorly for a part that costs less than a buck
 

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Discussion Starter · #19 ·
I got the fuse in the E-box under the hood out and it was fine. I'm in the middle of trying to get the relay housing out to check those. Regardless of pos 1 or 2, there is no priming on the pump at all.

According to yet another youtube video that middle 20a fuse is for the throttle, not sure if that is accurate or not, but all of the fuses in that bank are OK.

I got the bolt off for the relay housing, but I'm having problems getting the top clips to release. Anybody have any advice on getting the relay housing under the glove box out?

I haven't circled back to measuring the plug with the multimeter yet, but I'm going to ask this again in case anybody new on the thread has knowledge:

If the relay is bad, would there be current to the plug for the fuel pump?

Thanks,
 

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I haven't circled back to measuring the plug with the multimeter yet, but I'm going to ask this again in case anybody new on the thread has knowledge:

If the relay is bad, would there be current to the plug for the fuel pump?
If the fuel pump relay is bad, you will have no power to the fuel pump. Again, pay attention to the larger wires (16 Gauge, vs 22 Gauge) at the pump connector and MAKE SURE the pump connector is fully seated, this is another problem people have, you have to slide the bail sideways to fully seat the pump connector. The wire colors should be Blue with a White Stripe for +12 V and Brown for -12 V/Ground.

You can also jumper the fuel pump relay, assuming you have power coming into the fuel pump relay connector and power the pump up if needed. Terminal #6 at the fuel pump relay socket should be +12 V and you can jump it to terminal #2 the fuel pump socket to get power to the fuel pump wire Blue with a White Stripe.

As I recall you pull the glove box door to access the relays, about 10 Phillips head screws, easier than it sounds.

I think you swap the green relays.

Turn the key on and honk the horn, then pull what you think the horn relay is, swap them and also see if the horn still works.

Have you checked all the fuses in the regular fuse box? I know at times people mix up the fuses and put them back in the wrong slots from time to time as well, but this would not cause your car to randomly die.

Fuse 54 @ 15 Amp should be the actual power supply for the fuel pump.
 
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