[Beasty_916]

Hey all this is my first post here I am at a lost of what is going on with my 2014 f32 435i. It’s a very odd issue when the car starts in the morning it idles ok with an occasional engine shake for a second or two. After the car is warmed up from driving around I let it sit for about an hour or so and I come back to turn my car on and the engine is shaking and choking while the rpms rev up automatically to 2-3k rpm for a few seconds then comes down to a normal idle. It almost sounds like the car is going to stall when I turn it back on after engine is already warmed and has sat for an hour. It also doesn’t seem like it picks up as fast anymore almost like it’s in limp mode. Car has about 85k miles I’ve done all the maintenance on time and don’t drive insanely hard on the engine. I’ve replaced charge pipe, spark plugs, air filter, change oil every 5k miles, did fuel injector cleaner twice and poured chevron 91 octane gas, cleaned my MAF sensor twice. I have a feeling it is a bad sensor but just don’t know which one, I’ve scanned using obd multiple times with no misfires or any errors that stand out to me. I attached the obd reading so you can see what issues it’s reporting. I’ve also read multiple other forums but can’t find a fix so I’m going down a rabbit hole please help

Here is a video of the issue

[thejeremyman9]

Tuned or no?

Any other modes besides the CP?

If i had to just guess, it does sort of seem/sound like a fuel injector problem, but again, that's just a guess in the absence of more information. Did it get progressively worse over time?

[Beasty_916]

No tunes at all on the car. No other mods on the car bone stock other than I did a muffler delete 3 years ago. The issue did seem to get worse over time, as a test i was revving the car in park steadily at 4k rpm for a couple seconds and when i let go of the gas to let the rpms come down the engine was shaking. I have a feeling its something to do with how the car is getting air or fuel.

[TheJungatron]

yeah, lack of information code information here makes it hard.

If I would have to guess id do the following in order of price.

Check charge pipe and boot pipes again
clean MAF sensor again
replace air filter
swap plugs / replace plugs
replace coils / swap coils
fuel rail clean
replace fuel rail
replace fuel rail sensor

replace high pressure fuel pump and get turbos and go stage 3 :-)

Might be something simple or not.

Good Luck!

[thejeremyman9]

If it only happens when warm it could be something with closed loop (O2 sensors), but without a data log or more info its really just guessing. I personally don't think its anything with plugs/coils or you would have issues across the board. Does it ever smell rich?

[Beasty_916]

When you say smell rich are you saying like a rotten egg type of smell? I am asking because yesterday I was pushing the engine hard to see if would stall and when i came back it smelled like rotten eggs in the garage from the exhaust lol. I think i may order a new MAF sensor but ive cleaned it twice what do you think?

[thejeremyman9]

Originally Posted by Beasty_916

When you say smell rich are you saying like a rotten egg type of smell? I am asking because yesterday I was pushing the engine hard to see if would stall and when i came back it smelled like rotten eggs in the garage from the exhaust lol. I think i may order a new MAF sensor but ive cleaned it twice what do you think?

Rich would smell like fuel. Not sure why you would get rotten egg smell from the exhaust with a stock cat...

I don't want to make any specific recommendations without seeing more data or something because you are just going to end up throwing parts at the car.

[Beasty_916]

the Carly adapter has a function to log data and send it to me via email. I just dont know which logs i should be capturing. I put all the capable log data i can capture.

[thejeremyman9]

That's a lot... Can you just turn them all on and we can disregard what we dont need in post processing?

The key thing will be capturing a short log when the problem occurs so we can check for anything unusual

[Beasty_916]

I think it only allows 6 captures at a time but ill see what I can do

[Randy Johnson]

I had a very rough idle issue on my 435i that turned out to be the a bad coil. I replaced them all and the car runs like new. You could disconnect one coil at a time to see if you notice a difference.

[thejeremyman9]

These are probably a good starting point:
Air mass flow
Desired idle speed
Engine speed
Filtered rail pressure value
Manifold absolute pressure
O2 sensor int.
Rough running cylinder 1
Target throttle angle

[Beasty_916]

Originally Posted by Randy Johnson

I had a very rough idle issue on my 435i that turned out to be the a bad coil. I replaced them all and the car runs like new. You could disconnect one coil at a time to see if you notice a difference.

Yeah i thought about starting there and replacing the coils and MFA sensor.

[Beasty_916]

Originally Posted by thejeremyman9

These are probably a good starting point:
Air mass flow
Desired idle speed
Engine speed
Filtered rail pressure value
Manifold absolute pressure
O2 sensor int.
Rough running cylinder 1
Target throttle angle

Cool thanks man, I'm going to run those logs when I drive and when I turn the car back on after its been sitting. Thanks!

[cfm56d7b]

Originally Posted by thejeremyman9

Tuned or no?

Any other modes besides the CP?

If i had to just guess, it does sort of seem/sound like a fuel injector problem, but again, that's just a guess in the absence of more information. Did it get progressively worse over time?

Beasty_916, when was the charge pipe installed?

102001 can be thrown if charge pipe has not been seated properly. Worth investigating.

[Beasty_916]

Originally Posted by cfm56d7b

Beasty_916, when was the charge pipe installed?

102001 can be thrown if charge pipe has not been seated properly. Worth investigating.

Charge pipe was changed to VRSF April 2020 with no issues after the change. Sparks were changed at 60k miles.

[cfm56d7b]

Originally Posted by Beasty_916

Charge pipe was changed to VRSF April 2020 with no issues after the change. Sparks were changed at 60k miles.

Got it. Still suggest to check the fit - just in case.

[Beasty_916]

will do thanks guys, I just ordered new ignitions coils and will run the logs today and report back!

[Beasty_916]

I provided two sets of logs. Carly logs are little weird. The first set with start time of 16:42 is when I started logging right after cold start and driving around.

The second set of logs at 18:55 is after the car was warmed up and sitting for about an hour and half, I started logging before the car started shaking and auto revving at 18:55.

[thejeremyman9]

Originally Posted by Beasty_916

I provided two sets of logs. Carly logs are little weird. The first set with start time of 16:42 is when I started logging right after cold start and driving around.

The second set of logs at 18:55 is after the car was warmed up and sitting for about an hour and half, I started logging before the car started shaking and auto revving at 18:55.

You need to upload these to datazap

https://datazap.me/u

[Beasty_916]

Cold start logs
https://datazap.me/u/beasty916/log-1...=0-1-2-3-4-5-6
The breaks in the logs are me starting and stopping the logs on the carly app

Logs after car has been sitting for an hour
https://datazap.me/u/beasty916/logsa...=0-1-2-3-4-5-6

[thejeremyman9]

Originally Posted by Beasty_916

Cold start logs
https://datazap.me/u/beasty916/log-1...=0-1-2-3-4-5-6
The breaks in the logs are me starting and stopping the logs on the carly app

Logs after car has been sitting for an hour
https://datazap.me/u/beasty916/logsa...=0-1-2-3-4-5-6

Well you can see some strange behavior but unfortunately I am just not sure how to interpret the carly parameters or how to pinpoint what might be wrong.

You are still getting no codes, even shadow codes? I think MHD lets you scan for codes for free via their app, you might try that.

Without any codes or anything remote diagnosis may not be possible.