Z4-forum.com

Hello Gang,

Yesterday, I went to start my 03 E85 3.0 and the whole car started shaking with SEVERE misfiring...
I turned off the ignition, waited a few seconds and the re-started and all was fine....
No CEL- and again the car ran perfectly after restarting....

Recent Issues/Service: I just had the oil changed at an INDY in my area... Like 2 days prior to this...
Had a Fuel Pump wine about a month ago- thinking that this was bad gas... Ran a bottle techron and filled that tank with new fuel and it completely went away.
Changed spark plus 3 weeks ago... cleaned up slight missing at start-up with OEM's being in there at 94k miles…

The Z has only been driven 6k miles a year on average and was a retired persons toy... 2 owner
All service done at North Scottsdale BMW... Service history to best of my memory included a replacement spring, new drive belt, brakes and coolant flushed, brakes all 4 done at 30k and 75k.... basically the car was flawless and meticulous detail taken care of...

The car is an M-Sport Auto 3.0
95k miles

Can this be a fuel pump priming issue? Fuel Filter? at this mileage, I assume these wearable parts are starting to go?
Oil change, resulting in leaks in the air flow set up- checking filters etc.? This just happened 2 days after the oil change...

Really appreciate any input...

The shaking is something mine did when a coil packed up. Car shuddered and mis-fired.

A trip to EuroCarParts and around. £20 later, all sorted.

That was getting on a year ago and no other failures since. I now keep a spare in the boot.

Note - I did experience a few bad starts before it finally packed up. Mine was similar mileage to yours when it failed

Thank you for the feedback....

How did you know what coil pack went out??

https://www.amazon.co.uk/MAOZUA-Latest- ... nner&psc=1

I used one of those, I'm sure a bit of searching and you'll find them cheaper.

Other than that you could remove a coil lead at a time. A live coil lead removal will make the misfire worse. When you get to one that makes no change, that's the one

Put up a location, someone nearby may have a reader and be able to assist.

A CEL will go off I assume if I let it just keep misfiring? that would tell me a cylinder

I had this too. occasional lumpy running, gradually got worse over about two months, then engine fault light. Reset and all ok for a couple of days, then same again. I replaced all the coils (as if one is failing more are sure to follow) and plugs, no more problem.