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Starts then dies with other issues

12K views 11 replies 5 participants last post by  E39LOLZ  
#1 · (Edited)
Ok so here are the issues I'm having:

About 2 weeks ago I filled up the Beast (I hardly let it go down to 1/4 tank and I use 93 all the time) and the car would turn over but not fully start and then die. After about 10 attempts it finally started with no sputtering or any other driveable issues. This has happened about 5 more times since. My first thought is fuel related, though just to note my MAFS are about 22k miles old and I had my indy clean them out last month that cured a hesitation under WOT in 1st gear. My plugs, air filters are fairly new and my fuel filter is about 28k miles old so I have one for my indy to change out ASAP. Car currently has 139k miles and I believe I have the original fuel pump.

About two weeks before I had the starting issue, my drivers side halo lights stopped working. I figured it was a short since I had this same problem on my e39 525i on both sides, however, last night my xenon light began to flicker and stopped working. I turned off the car, went back out and restarted it and turned on the lights. The xenon light was lit but more of a blueish color and began to flicker once again then turn off. After doing some research it could be a number of things such as a short, ballast, xenon bulb (though that it was a module, not a bulb that controlled the xenon-newb question). Yes, my fault for being lazy and not getting the halo lights fixed in the 1st place so I made a call to my indy last night to see when he can check on my starting issue's and my drivers side halo's/xenon.

Also, I believe my battery/alternator are original, though those wouldn't be causing my starting issue's. As far as codes coming up:

E6: Drive-by-wire, throttle position failure (cleared last week and hasn't returned)
E8: Evaporative emissions purge valve functional check (keeps returning) so I assume its the fuel tank breather valve stuck under the plenum that could be causing my starting problems.
 
#4 ·
Wouldn't be surprised if it is the fuel pump, though it should be replaced as you said. I'm moving to Miami soon so I was planning on having the fuel pump, battery and alternator replaced as getting stuck along I-95 wouldn't be fun. I'll see what my indy has to say and I'll start pricing fuel pumps if I go that route sooner than later. I remember reading on this forum that there is a vendor who will supply a fuel pump and filter for $380 shipped? I'll have to search on that.
 
#6 ·
Sounds like fuel pump or fuel pump relay failing intermittently to me too. A while back I wanted to test a sensor response while the engine was cranking so I pulled the relay to prevent the pump running and started the engine to run it out of fuel. When it petered out, I restarted it expecting it to just crank, but it didn't - it did just what yours is doing, cranked, fired up grudgingly, ran real rough and then died. I had to quit before I burned the starter out, it just kept starting and dying.
 
#7 ·
Your issues sounds similar to what I experienced when my fuel pump started to go. Try unplugging the MAFs first and starting the car. If no change, then it is more likely than not the fuel pump. If you can quickly check the fuel pump relay, I would do that as well. However, from my own experience, I wouldn't bother replacing it until you replace the fuel pump.
 
#8 ·
Yeah, being an intermittent problem makes it more likely to be a burnt commutator in the pump than a problem with the relay, IMO. But if it dies completely, there are some simple electrical checks you can do to confirm if it is the pump or the relay.

You can also carry a 2' long piece of 2x4. If it won't start, pull out the rear seat and turn the key to the #2 position. If you can't hear the hum of the pump, bang on the sheet metal around the pump with the 2x4 to get it going again.
But I understand if you are a suit-clad professional making house calls, that may not be a viable option.
 
#9 ·
Thanks guys for your inputs. Yesterday the car started fine, though I just remembered this morning about the 'hum of the pump' so this morning I set the key position on 2 and I heard it hum. Anyway I just dropped it off at my indy and he will install the fuel filter and view my lighting issues. Will update....
 
#10 · (Edited)
Update:

Fuel filter has been replaced and so far after driving the car for about 3 days no starting issues and I always here the hum of the pump right at key position '2'. As for the xenon light, it was just a bulb (blonde moment as I should have checked that before). Indy had no time to check up on my halo lights on the drivers side as I needed the car back quickly but will do whenever I swing by.
 
#12 ·
It sounds like a hiss more than a hum actually. So far all week its been starting fine with no issue's so I hope it was my old fuel filter that was clogging things up.