BimmerFest BMW Forum banner

e39 Cranks But Does Not Start Or Even Sputter

9372 14
I just bought a BMW 540i e39 that sat for 2 years.

While everything looks good electrically, including fuses, the engine cranks but it has not even sputtered once in numerous stating attempts, until the battery was almost dead.

I suspect it's fuel related, so I disconnected the fuel lead hose from the top of the fuel pump housing and cranked the engine - no fuel exited the tank through the barb fitting.

My question is, when the ignition switch is on or cranking, should a functioning fuel pump blow fuel through the top of the pump housing if the hose is disconnected?

Any insight you can provide is greatly appreciated as I look forward to driving this awesome car to no ends...
1 - 15 of 15 Posts
I'm not sure if pump unplugged but, did you check for pressure at the schrader valve? There are a ton of threads on here for checking fuel pressure but, I would start at the schrader valve. If you push it in it will spray gas or autozone has a kit you could borrow to check exact pressure. Any codes?
I just bought a BMW 540i e39 that sat for 2 years.

While everything looks good electrically, including fuses, the engine cranks but it has not even sputtered once in numerous stating attempts, until the battery was almost dead.

I suspect it's fuel related, so I disconnected the fuel lead hose from the top of the fuel pump housing and cranked the engine - no fuel exited the tank through the barb fitting.

My question is, when the ignition switch is on or cranking, should a functioning fuel pump blow fuel through the top of the pump housing if the hose is disconnected?

Any insight you can provide is greatly appreciated as I look forward to driving this awesome car to no ends...
Early E39 V8s did not have a Schrader valve on the fuel rail.

The fuel pump primes the fuel line when the key is set to position 2. If you do not get this priming action, the pump, or the relay, may be dead.

You can test the fuel pump by jumping the fuel pump relay contacts.
I checked the connection at the pump and I have power. Do you suggest I jump it anyways?

As you mentioned, when the ignition key in position #2, I should see fuel shoot from the barbed fitting on the top of the fuel pump housing, but there's nothing coming out from the fuel tank, and there were only a few drops of fuel in the line when I disconnected it when it should have been full of fuel since I tried starting it a few times before disconnecting the hose... right?
Right. No fuel pressure, no start. If you have the output line from the fuel pump dc'd and no fuel comes out when you turn on the key to position 2, that's a problem. Should shoot fuel all over the place and make a huge mess doing that.

Don't try doing that with a good fuel pump!

This is a good excuse to buy a fuel pressure gauge, there not big bucks and come in handy, as you can see. while you're at it, buy a bmw specific code reader like Creator 310 (bout $60). I don't think this will be the only problem you ever have to solve with your car.

Jim

Oh one more thing, battery voltage is critical in this car. If you try and drive it with a low volt it will be really pissed.
I checked the connection at the pump and I have power. Do you suggest I jump it anyways?

As you mentioned, when the ignition key in position #2, I should see fuel shoot from the barbed fitting on the top of the fuel pump housing, but there's nothing coming out from the fuel tank, and there were only a few drops of fuel in the line when I disconnected it when it should have been full of fuel since I tried starting it a few times before disconnecting the hose... right?
try spraying starter fluid in to the air intake and see what it does. if it hits then, fuel is definitely your problem.
Sounds like a bad pump.

There has been at least one case where the electrical connections to the pump were bad, which prevented the pump from working. Looks like you'll have to remove the pump assembly to check operation of the pump motor.

I understand there are aftermarket pumps available that can replace just the your pump on your assembly.
I bought a pump off ebay last summer, free delivery, good price, it's working just fine.

Jim
Hi Jim, I just did the same thing, hopeful the $30 pump made in China will help me get fuel in the motor...
Spraying carb cleaner got her to sputter, pouring a little fuel in the air intake got her STARTED - Praise God!!!! She only ran for a few seconds, so I went ahead and ordered a fuel pump from eBay and am crossing my fingers the $30 pump will solve that problem... #Blessed
It'll be fine. Worst that can happen is it will last a year or two, enough time to get the car straightened out, then if it quits you can get a better one.

Change the oil!! First thing, change the oil!

I'd grab a set of plugs next after changing engine oil.

If it's an auto, get ready to change the trans fluid right away. Oh, and the rad fluid, after that.

Truth is, you're going to need to replace all the hoses, water pump, fan and fan clutch along with the radiator fairly soon. This motor will tolerate a bit of over heat, unlike the 6's but the car has been sitting and that's hard on a car. You're going to need to spend some money. Read up and get ahead of the things that will go wrong.

Jim
Hi Jim, I just did the same thing, hopeful the $30 pump made in China will help me get fuel in the motor...
Ed, even though I have power going to the pump, I went along with forum advice and tried to jump the fuel pump relay with a paper clip which glowed red in a hurry. Either I had the wrong relay (first one on the left from a 3 relay row with an extra dark green relay on it's own on the far right), or the pump is really seized up.

One thing I didn't mention is, the fuel pump fuse (#54) was blown when I bought the car... No brainer?
It is with great joy and an amazing amount of gratitude I would like thank everyone who contributed to my beloved 1997 BMW 540i e39 coming back to life this evening shortly after I replaced the fuel pump with a $30 part I got from eBay.

It turns out the issue was the pump all along, as the old pump's protective screen shredded over time and small pieces of screen were sucked into the pump causing it to seize up, then fry the corresponding fuse.

After not running for over 2 years, I admit she's running a little rough, I plan on taking the fuel out and changing oil/fluids asap.

Is it just me or are 540i's the best cars ever built?

#Blessed

No, not just you, I'm in there with you as are quite a few around these parts. :) The e39 has been written up in car mags as the best sedan ever made several times, I think only surpassed in resent years by the Tesla.

Glad you brought another one back from extinction!!

Jim
It is with great joy and an amazing amount of gratitude I would like thank everyone who contributed to my beloved 1997 BMW 540i e39 coming back to life this evening shortly after I replaced the fuel pump with a $30 part I got from eBay.

It turns out the issue was the pump all along, as the old pump's protective screen shredded over time and small pieces of screen were sucked into the pump causing it to seize up, then fry the corresponding fuse.

After not running for over 2 years, I admit she's running a little rough, I plan on taking the fuel out and changing oil/fluids asap.

Is it just me or are 540i's the best cars ever built?

#Blessed

1 - 15 of 15 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top