How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Juan Crespo Your Own Question
Juan Crespo
Juan Crespo, Tech Trainer
Category: BMW
Satisfied Customers: 1491
Experience:  A.S.E. Master Technician, Advanced Level, Emissions - Asian, Domestic, & European
Type Your BMW Question Here...
Juan Crespo is online now
A new question is answered every 9 seconds

2000 BMW 740i M62. Ran great until low on fuel, made it to

Customer Question

2000 BMW 740i M62. Ran great until low on fuel, made it to the gas station before it died but was sputtering. Filled with gas, started right up, and ran great. 2 miles down the road it lost power, sputtered, and died. Towed home. Changed the fuel pump, fuel filter, crankshaft position sensor, spark plugs, fuel pump relay, all fuses are good including the 5 fuse cluster for the DME under the hood. I bypassed the fuel pump relay by jumping the right terminals and the pump ran and pressurized the fuel rail to 50 psi, no pressure, with the relay in while cranking however. When changing the spark plugs I shot a squirt of oil in each cylinder to try establishing compression. Still no start. What could have happened simply by running almost out of fuel considering everything I've done so far? I also checked the temp sensor that sometimes draws coolant up the loom. Help!!!
Submitted: 25 days ago.
Category: BMW
Expert:  Chris (aka-Moose) replied 25 days ago.

Welcome, I'm Chris (aka Moose) I prefer to work when others don't, I am here around lunch and after dinner till after midnight.

Have you verified good compression and ignition spark?

Will it start briefly on starting fluid?

So far I believe you may have sucked up the junk in the bottom of the tank and clogged your fuel injector up so that they can no longer spray fuel.

This is my 1st answer, but does not have to be my only answer. You the website and myself expect you to have a ~~~5 STAR EXCELLENT~~~ experience with my help. Please let me know if you are pleased by selecting a star rating above or by replying and saying your pleased. Not rating or rating 1-2 stars does not benefit you nor me in any way. Follow up and reply as often and when needed, there is no extra charge to do so.

Thanks Moose.

Customer: replied 25 days ago.
Hi Chris, thanks for the response. I thought I had, but maybe I did not indicate. I replaced the fuel pump and I also replaced the fuel filter. While cranking their is no power to the fuel pump, at the fuel pump relay I verified this by testing the harness that connects to the pump while cranking, no voltage. I put a fuel pressure test kit on the fuel rail and cranked it as well, no pressure. I verified the new fuel pump and filter work by jumping the fuel pump at the fuel pump relay and engaging it manually, it does come on and pressurizes the rail to the correct 3.5 bars (50 PSI), however no power is sent to the fuel pump while cranking. The DME is not energizing the pump. I tried starter fluid and although the car tried to start it did now and once the starter fluid evaporated it returned to normal cranking. I also changed the crank shaft position sensor. Nothing
Customer: replied 25 days ago.
Thanks for the response and I hope you can help me resolve. I was told the DME relay might go bad. Do you know where this is on my car?
Expert:  Chris (aka-Moose) replied 24 days ago.

I did misunderstand.

When you jump the pump manually will the car then start?

Customer: replied 24 days ago.
Hi Chris
No, the car will not start when I jump the pump and leave the pump running while cranking the motor. I also tried started fluid, the car will try to start, but one the starter fluid evaporates the cranking returns to a no spark no fuel scenario.
Customer: replied 24 days ago.
I read a few places that the DME recognizes crank and idle through the cam and crank shaft position sensors, I changed the crank pos. sensor. I just find it hard to believe something electrical related went out because I was low on fuel. Is there a DME relay on this car that might have gone out?
Thanks for your help, I need to get this thing going ASAP!
Expert:  Chris (aka-Moose) replied 24 days ago.

Here is a wire diagram for the engine controls.

Since it will run on starting fluid that confirms spark and compression is good. Since it will not run with the fuel pump jumped, this leaves the fuel injectors not pulsing as one of the concerns. Are the injectors powered on the red/white wire wit the key on? Is fuse 17 10 amp powered with the key on?

Customer: replied 24 days ago.
Chris I think you may have misunderstood my response. The car will not run on starting fluid. When I spray starting fluid into the intake the car will try to start by jumping RPMs a bit, but stops doing that once the fluid evaporates. The car will not run or idle at all even for a second. I will check the injectors first thing in the morning.
Expert:  Chris (aka-Moose) replied 24 days ago.

Do a continuous spray of starting fluid into the open throttle body to see if it will start even if briefly.

Customer: replied 24 days ago.
Also, as I stated before as well, the fuel pump will not run unless I jump it, the DME is not energizing the pump during crank. I did change the fuel filter and on this vehicle the fuel filter also has a fuel pressure regulator on it.
Expert:  Chris (aka-Moose) replied 24 days ago.

It seems you would like to get back on the waiting list to see if another can help. I am going to opt out now and remove myself from this discussion. Best if luck

Customer: replied 24 days ago.
fuse 17 is hot with the key on and no the injectors are not activating.
Customer: replied 24 days ago.
Thanks for your help, best of luck to you as well.
Expert:  Juan Crespo replied 23 days ago.

Hi there. Different expert here.

That sounds like your EWS anti-theft immobilizer system has been activated and is preventing fuel pump and ignition system operation. Try arming and disarming the system as you normally would and see what happens.

Customer: replied 23 days ago.
I have armed and disarmed the system many times over the last month while trying to start this car. Will the EWS still allow the car to turn over? My car will turn over (crank), but won't start.
Expert:  Juan Crespo replied 23 days ago.

EWS-II will only disable ignition signal and fuel supply while EWS-III will disable starter engagement as well. There are inexpensive tools out there that allow for temporary EWS by-pass. Click here to see example. Otherwise, you would need OSS or equivalent diagnostic tools to find out what is preventing the DME from energizing ignition and fuel systems.

Customer: replied 23 days ago.
Thank you for that valuable info. I have a 2000 BMW 740i (E38 M62), would you happen to know which EWS I might have?
Expert:  Juan Crespo replied 23 days ago.

2000 was a transition year, but based on the symptoms you describe I'd say you have the EWS-II.

Customer: replied 23 days ago.
The car was running great, ran low on fuel, I fueled it up, ran great for 2 miles then acted as though it was running out of fuel again, died, hasn't started since. Does the EWS go bad in a scenario like this? I turn the key to position 2, and under the hood I can hear a very faint quiet sound of the alarm going off, very faintly. The car will turn over, but not start. Outside of expensive diagnostic and EWS bypass tools, is there anything I can do on my own to narrow this problem down? Thanks for your time and help, expect the best rating.
Expert:  Juan Crespo replied 23 days ago.

I'm sure that other experienced BMW techs will also tell you that, as these vehicles get older, the anti-theft systems can go bad on their own for no apparent reason.

I do wish there was a work around that I could share with you. As it is, I don't know of any way to diagnose this type of issue that doesn't involve using a capable scan tool and perhaps even a scope.

Customer: replied 22 days ago.
Ah. So just to clarify, you are saying there is nothing I can do to diagnose the no start issue with my BMW 740i, that I have to take it to the dealership to have it scanned on a diagnostic machine? Are there no checks or balances I can run myself to infer possibly the cam shaft position sensors or a faulty DME relay? Might so be able to check the resistance on those cam sensors or jump the DME relay to see if the car will start? I was really hoping to consult with a professional such as yourself and avoid the costly maneuver of towing my vehicle to the dealership. I am going to click the play button and give a perfect rating, I just want to make sure we have exhausted any and all possible scenarios and DIY tests that can be done.
Expert:  Juan Crespo replied 21 days ago.

It seems you're reading something I haven't posted - what I did post was "I do wish there was a work around that I could share with you. As it is, I don't know of any way to diagnose this type of issue that doesn't involve using a capable scan tool and perhaps even a scope."

As is, it looks like I won't be able to help you; so I'll opt out of the chat to let others try. Please do not rate or reply until another expert responds or the site will cycle this back to me.

Customer: replied 21 days ago.
Well I find it hard to believe there isn't a ohm test that can be done to the cam shaft position sensors, or a test of the main DME relay, or possibly a test to determine whether I'm getting spark or whether the injectors are firing. I'll pay you for your time and effort. Thanks for your advice, Juan.
Expert:  Juan Crespo replied 21 days ago.

Reading your last post I get the idea that you think I'm holding back and not sharing with you some sort of procedure for which no specialized diagnostic equipment is needed; that is simply not true. As hundreds of customers can attest, my only goal is to help people who need the kind of technical assistance I can provide. I'm really sorry you got the wrong impression of what an expert on this site can and cannot do.

Now, as I opt out once again, please refrain from replying until another expert responds or the site will automatically cycle this chat back to me.

Thank you.

Customer: replied 21 days ago.
No no, I'm not getting the impression you are holding back, quite the contrary I think you are being responsible and not suggesting I do something that might harm my car. I appreciate your candor and help, right now I am trying to end this question seminar by rating and paying. I have decided to tow the car to a technician whom can diagnose it with a scan tool and a scope. I keep clicking the finish by rating button and it won't let me rate and pay. I might have to start another question to a professional to figure out how to rate and pay for this question! Don't bother referring me to another expert, I trust your advice and am going to take the vehicle to a diagnostic professional with adequate tools. Again, I am trying to rate and pay but the button won't let me finalize this question seminar.

Related BMW Questions