[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.

[David Kunitz]

I am very happy to read this post!

I have recently bought a very high milage 2012 335i F30 and I am having a very similar issue.

https://www.bimmerpost.com/forums/sh...php?p=31014051

I posted my issue here yesterday, see if you have the same issue!

[SpoolinAddict]

When I put in new spark plugs and tuned my car, it went into limp mode and had misfires/drivetrain malfunction. Just because your spark plugs are new, doesn't mean they can't be DOA right away. Switched out the bad 1 and ran perfect.

[fijigabe0]

Going back to basics - was the problem over a prolonged period of time or during a short period? You have basic bolt-ons, so I don't think that's the issue. If this is a short-term issue, have you tried draining the tank and putting new gas in (I'm thinking bad gas or water in the fuel tank)?

[Divury]

Originally Posted by David Kunitz

I am very happy to read this post!

I have recently bought a very high milage 2012 335i F30 and I am having a very similar issue.

https://www.bimmerpost.com/forums/sh...php?p=31014051

I posted my issue here yesterday, see if you have the same issue!

I would say the main similarity is that the throttle level is consistently low across both of our problems. Probably something to note.

[Divury]

Originally Posted by fijigabe0

Going back to basics - was the problem over a prolonged period of time or during a short period? You have basic bolt-ons, so I don't think that's the issue. If this is a short-term issue, have you tried draining the tank and putting new gas in (I'm thinking bad gas or water in the fuel tank)?

This has been happening now for 3 or 4 months. Took it to a good shop. They read valvetronic and air mass faults, cleared and relearned, updated DME per service bulletin. Issue is persisting, so ruling out old dme software as a cause (which i’ve seen on older forums here)

[Divury]

Originally Posted by SpoolinAddict

When I put in new spark plugs and tuned my car, it went into limp mode and had misfires/drivetrain malfunction. Just because your spark plugs are new, doesn't mean they can't be DOA right away. Switched out the bad 1 and ran perfect.

Only reason I think this might not be the cause is because if I had a bad spark plug it 1) wouldn’t have happened both before and after changing them and if it did 2) would likely be more consistent misfiring and not once every month or so.
Maybe im wrong.