my m5 starts, and then dies immediately! HELP!

[ellinopedo182]

I dont know what happened, the car has been driving nicely and it feels more powerful then ever. All of a sudden, i had to go to the supermarket earlier today and i start up the car, everything sounded right and within a few seconds, the car dies on me. I have tried it at least 10 times and this same thing happens. The car starts, and it bogs, and then dies. I have installed new headlights Proj39 in the last few days, but i doubt that has anything to do with it. Anyone have any ideas?

[NEVER2LOW]

Didn't you do the AFE Intakes as well? Check the intake area for anything out of the ordinary (MAFS too).

[e39dream]

cam position sensor would be my guess. do you have a obd-II scanner or access to one? get the codes and we'll know what's wrong.

Were you in Indiana a couple nights ago on US 41? I saw/ heard a really mean sounding black e39.

[ellinopedo182]

Didn't you do the AFE Intakes as well? Check the intake area for anything out of the ordinary (MAFS too).

yeah i did, i looked at them and they look normal, i was getting scared maybe the intake fell off bc maybe it wasnt secured enough to the hose and cicadas flew into the engine through the bumper intake holes i made. We have like a million cicadas, i killed at least 5 in 10 minutes of driving earlier today.


Could the maf's cause the car to die? I did try cleaning them a few days ago, maybe i made a mistake or screwed them up? The car had been driving good for the past few days.

[ellinopedo182]

cam position sensor would be my guess. do you have a obd-II scanner or access to one? get the codes and we'll know what's wrong.

Were you in Indiana a couple nights ago on US 41? I saw/ heard a really mean sounding black e39.

i was on US41 but in the chicagoland area sorry probably wasn't me.

what do u guys think of the fuel pump relay?

[Gumbi4u]

i was on US41 but in the chicagoland area sorry probably wasn't me.

what do u guys think of the fuel pump relay?

It could be but try to fill up the tank and see what happens. Could be the fuel pump itself. Or as simple as the fuel filter but honestly I dont know how these bimmers act when the filter is clogged to crap. Try the full fuel tank bit and see what happens. If it works just fine then let it run its course. If it starts to shut off again, its the pump.

[ellinopedo182]

It could be but try to fill up the tank and see what happens. Could be the fuel pump itself. Or as simple as the fuel filter but honestly I dont know how these bimmers act when the filter is clogged to crap. Try the full fuel tank bit and see what happens. If it works just fine then let it run its course. If it starts to shut off again, its the pump.

its easier to fill up the car if i could actually get it to a gas station lol. i do have +1/4 tank of gas, so i dont know why it would be a problem. I'm going to try to install the new MAF's i got, but im skeptical about that being the problem.

[umnitza]

sounds like MAF.

[e39dream]

mafs not the problem- it will run with them unplugged (it should)

[ellinopedo182]

mafs not the problem- it will run with them unplugged (it should)

thats what i thought. Its weird how all of a sudden the car can just die after driving normal and perfect.

[Gumbi4u]

Yep Maf isnt the issue here. Most likely a fuel supply issue. Filter (best case scenario) and the pump (worst case)

When was the last time you changed the fuel filter?

[e39dream]

the cam position sensor causes this type of no start, was fine the other day issue. I dunno if the m5 has one or two cps sensors but I'd search m5board.com and see what comes up- I think the sensors are less than 100 bucks each.

[ellinopedo182]

Yep Maf isnt the issue here. Most likely a fuel supply issue. Filter (best case scenario) and the pump (worst case)

When was the last time you changed the fuel filter?

Ok, so... i went outside to start the car up again, again... no luck. Did it three times. I'm like wtf, so i opened the hood and disconnected the MAF sensors wires and started up the car no problem... other than the rough idle if u tried pressing the gas, but it didnt die on me. Reconnected the maf's wires, die on me again. Disconnected one last time, started the car no problem (still idled hard every time i pressed the gas slightly). I think it may be the MAF's, i will try it and see whats going on. Hopefully my fiance will be here soon with the torx driver.

[Gumbi4u]

Ok, so... i went outside to start the car up again, again... no luck. Did it three times. I'm like wtf, so i opened the hood and disconnected the MAF sensors wires and started up the car no problem... other than the rough idle if u tried pressing the gas, but it didnt die on me. Reconnected the maf's wires, die on me again. Disconnected one last time, started the car no problem (still idled hard every time i pressed the gas slightly). I think it may be the MAF's, i will try it and see whats going on. Hopefully my fiance will be here soon with the torx driver.

And your not pulling any codes? thats weird but weirder things have happened.

Keep us in the loop. Good school lesson

[brandon5069]

sounds like MAF.

Matt the M5 mechanic????

[e39dream]

hmm- maybe they mafs are really dirty or just faulty. did you put on new air filters or something? those performance air filters you oil are known for killing the mass air units.

[Gumbi4u]

hmm- maybe they mafs are really dirty or just faulty. did you put on new air filters or something? those performance air filters you oil are known for killing the mass air units.

I think he said he already cleaned them. But what I find odd is the minute he plugs them in, it shuts down the engine. Maybe a resistor is shot on the sensor board inside the mafs.

[ellinopedo182]

i start torxing the mafs and i notice the previous owner had put one new MAF because the torx screw was 5pt for one and the original 6pt for the other. So now i have to go back to pepboys to get a 5pt too... damn i hate driving the tiburon. I think the performance airfilters may have dirtied the maf's but not positive.

[scbimmer]

the cam position sensor causes this type of no start, was fine the other day issue. I dunno if the m5 has one or two cps sensors but I'd search m5board.com and see what comes up- I think the sensors are less than 100 bucks each.

+1
Cost is around $150 each

[ellinopedo182]

no go, replaced the MAF's, car wont even start now. i mean, its trying but it wont start like before when it would start and die immediately.

[ellinopedo182]

does anyone know where the ecm is on the m5? fuel pump fuse, etc. i removed both air filter boxes in the engine compartment but there was no ecm unit

[azaytsev]

does anyone know where the ecm is on the m5? fuel pump fuse, etc. i removed both air filter boxes in the engine compartment but there was no ecm unit

right side, below pollen filter

[jamesdc4]

Wow. I thought for sure it was the MAF. I can start my car and if I back the MAF out it will shut down.
Even if the CPS is bad, the car should still run. The CPS only functions at start up to let the fuel injection system know the orientation of the camshaft. My 540 was throwing the CPS code but still ran. It runs a hell of alot better since I replaced it.
Wierd problem.
GL troubleshooting.

[ellinopedo182]

i just added gas maybe that was the problem, nope. i am going to check the fuse tomorrow and if that doesnt work, i will take it to a mechanic.

[killcrap]

sounds like a bad MAF. consider reading out fault memory.