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First time ever, my beast choked on me and I had to call a flat bed truck to transport it to my house so my mechanic can work on it tomorrow.

Drove the beast around town for about 4 hours today, outside temp is about 80, then all of a sudden - pressing the gas pedal, engine chokes and misfires badly.

At the stop light, engine revs fine, but once I put it in gear and tried to accelerate - engine again chokes and eventually died. So I pulled over.

I let the beast rest for 15 minutes. started right up, no problem revving the engine. Put it in gear, drive off, accelerates fine on first gear, then starts choking again on 2nd gear, engine eventually died again.

So I finally called AAA and had a flat bed take my beast to my house so my mechanic can take a look at it tomorrow.

I called my mechanic, his initial thoughts - possibly fuel pump going bad.

He said he'll check fuel pressure tomorrow and start from there.

I just got done pulling the codes:

C9 = Misfire Cyl 6.
C5 = Misfire Cy 2
CC = Misfire multiple cylinder
C4 = Misifre Cyl 1
90 = Fuel control cyl 1 - 4
91 = Fuel control cyl 5 - 8
57 = After cat oxy sensor 1 - 4
58 = After cat oxy sensor 5 - 8

Thoughts? Thanks in advance.
 

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I think you're screwed!

J/K :)

I'm putting coin down on the fuel system (a real shock, I'm sure...). Now, whether it is the fuel pump, or a clogged filter I'm not going to guess :)

I can tell you this: I ran out of gas today (don't start, the car said 20 miles to empty and I was late...). My codes were: 90, 95. So, I'd guess you have a similar issue.

btw, when you run out of gas in our cars you really don't get any warning. You pretty much are driving along at 90 mph on the highway and then BAM, you're out of gas....

I'm sure you'll be fine Dan - but make sure he checks the simple stuff first!

d-
 

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Discussion Starter #4
Sorry to hear your beast ran out of gas today Doug.

It happens to most of us.

Take it easy bud.

Dan

I think you're screwed!

J/K :)

I'm putting coin down on the fuel system (a real shock, I'm sure...). Now, whether it is the fuel pump, or a clogged filter I'm not going to guess :)

I can tell you this: I ran out of gas today (don't start, the car said 20 miles to empty and I was late...). My codes were: 90, 95. So, I'd guess you have a similar issue.

btw, when you run out of gas in our cars you really don't get any warning. You pretty much are driving along at 90 mph on the highway and then BAM, you're out of gas....

I'm sure you'll be fine Dan - but make sure he checks the simple stuff first!

d-
 

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Dan,

Sorry to hear. A faulty fuel pump seems a likely cause.

Keep us posted.
 

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Sorry to hear that Dan...fuel pump or o2 sensors ...:thumbsup:
 

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Same sort of thing happened to me about a month ago, I put it down to bad petrol or maybe and this is just a theroy of mine, a flake of what ever (dried petrol if thats possible) came of the bottom of the tank when it was nearly empty and got sucked into the fuel line.
 

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Keep us updated when you figure out the problem.
 

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Discussion Starter #10
Thank you, Thank you, Thank you to all of you for your kind post.

Yes, there's good info to learn here.

I will let you know all know once my beast is fixed that way if you experience the same thing in the future - you will all know what the likely culprit is.

Have a great Sunday.
 

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Looking forward to hearing the outcome...

All will be well soon!
:cheers:
Dave
 
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Dan,

I know your battery is still new but kindly check it and your thermostat....just a thoughtL:)

The weather today here is excellent for detailing (so it's detailing Sunday for me):D
 

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Same sort of thing happened to me about a month ago, I put it down to bad petrol or maybe and this is just a theroy of mine, a flake of what ever (dried petrol if thats possible) came of the bottom of the tank when it was nearly empty and got sucked into the fuel line.
Not likely. The fuel pickup (in the right hand tank) ALWAYS picks up from the bottom of the tank, and fuel goes to the engine from the right hand tank only ... regardless of fuel level. The siphon pump (left hand tank) which keeps the right hand tank filled with the maximum amount of gas available or all that it can hold, could be bad (common). The PRIMARY fuel pump (high pressure for fuel injectors) is under the floor under the driver (in the U.S.), near the main fuel filter (bigger than a can of soda pop).

The gas tank (which is under the rear seat and straddles the drive shaft) is built like it is two tanks (but, in reality, it is one piece). And, it is plastic ... no rust to form ... I think the fuel sensors have been modified as the older BMW ones were affected by the gas additive MTBE (which is no longer used). Not likely that they would rust. Also, I believe there is a small filter in the right hand tank on the sensor ... at least, there used to be.

To check your siphon pump ... unlock the console and go to Test # 14 (I believe). Cycle through 5 messages ... should all be = 00 000 0000. If there is one that begins in D7, your siphon pumb is malfunctioning (leaving unused gas in the left hand tank, and requiring you to fill up more often). That could lead to running out of gas early.

The codes, like 'D7" have to be reset by the dealer. "D7" and "C7" are the only ones I know ... the dealers know the rest. The group of three digits are set by the severity of the error, and cycle down, one digit at a time, each time the car is started. If your D7 ocurred a long time ago, the three digits may be 000 by now.
 

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^^^ This is the 'other' fuel pump issue that can look like 'no fuel'....

GL

A
 

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Sorry to hear about your trouble - hope you get it sorted soon.

I would also think along the fuel pump route, the mis-fire codes are obviously stored as you had very obvious misfires, the post Cat O2 sensors should not effect the performance and certainly should not have helped cause a mis-fire, most likely those errors were also thrown as a result of the mis-fires.

The only thing in the back of my head is this, if it is to do with the fuel pump would the mis-fire codes not have been due to fuel starvation and throw code 95 (Misfire w/ empty fuel tank) ?

Just a thought,

Richie.
 

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Check console TEST # 14 first. And, go from there.
 
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Discussion Starter #19 (Edited)
Update

Hi Chris. Thanks for the follow up.

So, I took my beast to my mechanic yesterday (he's a certified BMW mechanic).

On my drive over to his shop (only 2 miles away from my house) the beast ran fine.

My mechanic took it my beast out for a test drive with me. Beast ran super fine.

Boy I tell you, you really want to feel the power of the M5 - be a passenger once in a while and feel the torque and the rush when the driver mashes the pedal. Whoooaaa. He was very impressed too.

Anyway, his input is, which I agree, it's fuel pump going bad and he recommends replacement. I told him - Lets go ahead and do preventive maintenance and not wait until it completely fails. I hate car's breaking down on the road.

So I asked him to go ahead and replace the fuel pump and the fuel filter.

I left my beast with him, I get it back tomorrow afternoon.

Will report again once everything is done.

You folks take care.

Dan,

Any word from your tech?
 

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Nice...thanks for the update:cheers:
Hi Chris. Thanks for the follow up.

So, I took my beast to my mechanic yesterday (he's a certified BMW mechanic).

One my drive over to his shop (only 2 miles away from my house) the beast ran fine.

My mechanic took it my beast out for a test drive with me. Beast ran super fine.

Boy I tell you, you really want to feel the power of the M5 - be a passenger once in a while and feel the torque and the rush when the driver mashes the pedal. Whoooaaa. He was very impressed too.

Anyway, his input is, which I agree, it's fuel pump going bad and he recommends replacement. I told him - Lets go ahead and do preventive maintenance and not wait until it completely fails. I hate car's breaking down on the road.

So I asked him to go ahead and replace the fuel pump and the fuel filter.

I left my beast with him, I get it back tomorrow afternoon.

Will report again once everything is done.

You folks take care.
 
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