[Divury]

I have a 2013 335i F30 with 80k ish miles. New plugs and coils. New chargepipe.

This issue has happened so far 6 times now.

The first 5 went like this:

Low-moderate throttle, the car will have a loud pop, and then throw itself into limp mode and fully cut power. Drivetrain malfunction appears. Check engine light appears, and then promptly goes away. Car goes into neutral, turn it off. Then it doesnt start. Have to reflash BM3 to get it started again.

Took it to Precision Sport Industries. They diagnosed it as old DME software per SI B12 36 15.

"Received vehicle in proper working order. Started and ran without issue. Read vehicle fault memory and found multiple valvetronic faults along with an air mass plausibility fault. Both fauls had an occurence of 1 time. Carried out valvetronic test plan. Valvetronic was cycled 200 times and reached end stops 5 times without issue. Reset valvetronic fault counter and re-learned system. Referend SIB 12 36 15 which outlined intermittent power loss as described by customer. Applicable faults were stored. All test plans passed mechanically so the next step at this moment would be to program the DME and perform a software update and recheck"
"Performed software update. Rechecked and found all good at this time."

After this service, the car had the exact same power loss while accelerating with very little throttle. Limp mode, no start, etc.

Car starts fine right now. Idles fine, no knock, no sputtering, nothing. The power loss to me seems completely random and it's happened under various different kinds of load.

Full list of modifications:
AWE Touring Exhaust
CTS Turbo CAI
VRSF Charge Pipe
VRSF Intercooler
VRSF Catless DP

Car also has a valve cover leak currently. Not sure if/how this could cause this sort of issue.

Has been on multiple different BM3 maps. Each one has the same problem.

Has anybody experienced this before? Any information on this would be good. I don't want to sell this car but it's happening more frequently and it's making daily driving the car a bit scary.

[thejeremyman9]

Valve cover can be a vacuum leak, can potentially explain air mass code

[Divury]

Originally Posted by thejeremyman9

Valve cover can be a vacuum leak, can potentially explain air mass code

Could this have any affect on the valvetronic? I was getting codes for both.

[spiff56747]

I hate valvetronic. Can't help your particular issue but hope you get it fixed.