Help very depressed

[Debe]

Hi I joined this site after I bought my first x5
It has been a wealth of information as it helped me pick the correct angle eye bulbs and steer me towards carphonics for the tv upgrade but now I have a problem

It a e53 4.4is o3 build date and it's off a couple of cylinders
I replaced 8 coils and 8 plugs sent off the injectors for rebuilding/cleaning and changed the fuel filter
after the fuel filter was changed it was fixed ........ For all of about 26 miles then it dropped off a couple of cylinders again and now I'm depressed
What else could it be
I had a snap on solus on it to day an it says misfires 6/7 cleared it them after 10 min codes said 6/7/1/2
Also both O2 sensors bank 2 before and after cat. Would this affect it

Now I bought it cheap cos it was off a couple of cylinders and the door handle had broken and needed the tv upgrade ect ect  but it's now getting me down what else could it be
Would a 1.40 reader be any better
  Cheers for any help in advance Dave

[JimmySpeed]

Have you had the compression tested?

A previous owner driving it when it overheated can crack the head or destroy the head gasket. Not a nice repair (speaking from experience) and with a 4.4 an engine swap would be easier than repairing it. But that is a worse case scenario. Check compression and go from there though.

Sent from my SM-N9005 using Tapatalk

[Debe]

Hi the x5 has not been over heated it only bought it as it was a mates and I
Did a compression test when we changed the coils
Could it be a electrical fault
I tested all the wires to day for continually and the wires to the coils are all
Intact 
What else can I check ??

[kkx5]

Hi. is Yours face lift? 4.4i or 4.6is ? There was no 4.4is. Is it missfire on cold start up or when You drive?

[Debe]

Hi
It's a facelift 4.4
It's off at least one cylinder on  start up and when out for a drive you can feel it to
It seems to come and go if I rev it a tickle the engine smooths out  could it be a fuel pump issue would a bmw scanner1.40 help me ?

Cheers

[Steamyrotter]

Cam / Crank shaft sensor?
If nothing else a cheap test..

How is the battery & alternator???
Many documented cases of electrics playing up due to iffy supplies

[kkx5]

Ok. Its a n62 engine. Its not that easy with it. Very, very rarely spark,coil plugs will gave You misfire. Most of cases its valvetronic unit, vanos unit, timing chain jumped. You need at least bmw dis, isss, autologic to diagnose it.

[Ubatoid]

I spent weeks arsing around with a misfire on mine. New plugs and coils just as you have. My was fixed when I sent my cheap faulty coils back and fitted some proper bosch ones. I had 6 out of 8 dodgy ones. Do you have lpg ?

[shadrack]

[quote="Debe"]
Hi I joined this site after I bought my first x5
It has been a wealth of information as it helped me pick the correct angle eye bulbs and steer me towards carphonics for the tv upgrade but now I have a problem

It a e53 4.4is o3 build date and it's off a couple of cylinders
I replaced 8 coils and 8 plugs sent off the injectors for rebuilding/cleaning and changed the fuel filter
after the fuel filter was changed it was fixed ........ For all of about 26 miles then it dropped off a couple of cylinders again and now I'm depressed
What else could it be
I had a snap on solus on it to day an it says misfires 6/7 cleared it them after 10 min codes said 6/7/1/2
Also both O2 sensors bank 2 before and after cat. Would this affect it

Now I bought it cheap cos it was off a couple of cylinders and the door handle had broken and needed the tv upgrade ect ect  but it's now getting me down what else could it be
Would a 1.40 reader be any better
  Cheers for any help in advance Dave
[/quote]

sorry to point out the obvious but you need someone with a better fault code reader/scanner before you spend £100s on new parts that are not needed, does the misfire move if you swap plugs/coils/injectors over from a known good cylinder, also do a compression test