Noob from UK - 135i N54

Phillstine

Lurker
Dec 6, 2021
13
0
0
Hi Guys,

Currently have a 135i N54 (auto)

Previously had 2 x 335i (auto/DCT) and another 135i (Manual) and M135i(Auto) not a brag, more of a yes I've got grey hair and an empty wallet at 28!

Hoping someone on here might be able to help with an issue!

Cheers!
Phill
 

Phillstine

Lurker
Dec 6, 2021
13
0
0
Hey!
I popped a thread up on the data logs and N54 troubleshooting but seems to keep disappearing :S

"I've been having a problem with my car for a while and have replaced loads of things to no avail.

On starting only when cold and left for over 24 hours the first start up is rough and stumbles and misfires badly for 10 seconds.

I've replaced Injectors to Index 12
HPFP replaced
Low pressure Sensor replaced
Sparkplugs replaced
Coil replaced
Vanos Solenoids replaced

I don't get any codes, I notice that when starting it's fine until the JB4 wakes up (Needle Sweep) then starts running poorly so I removed the JB4 and it would start fine every time. I then Mapped the car with MHD and the problem is back, flash back to stock starts perfect again.

JB4 Issue? - YouTube - Despite the title the issue isn't specific to JB4

Is there something in the fuel tables on MHD/JB4 that effects start up different to stock?"