[karim_r]

Hi everyone,

Not really a new member here, but this will be my first time posting in the 5 series forum. Hopefully i can get a few answers regarding issues i'm experiencing with my 53,000 mile F10 with N20 engine.

Here are the details:

- Slight vibration during warm start up (normal cold start).
- Sometimes long crank, however engine starts up the first time.
- When, waiting at red light in Drive you can feel the engine slightly shaking and before taking off there's a slight delay before the car accelerates.
- When accelerating to overtake, there is a slight delay before the car downshifts and increases speed.
- Fault Code 102001 (Air Mass Plausibility too high), however this fault code is able to be deleted. and happened approximately 300 miles ago and has not popped up since.
- Fault Code 118002 (Air-fuel Mixture Too Rich) is the only remaining fault code.

Mods on the car:
- Bootmod3
- Catless Downpipe
- Chargepipe

The independent workshop that scanned the car believes it's the Mass Air Flow sensor, since it has a high reading between 22.2kg/h to 24/kg/h at 862rpm (with the AC on).

I have tried cleaning the MAF with CRC MAF Cleaner and still having the same issue.

The workshop suggested it is the bootmod3 causing issues, however since the car has been running fine after the bootmod3 flash, i don't believe its the cause of the issue. Should i proceed in replacing the MAF Sensor or is it normal for a tuned car to have a higher MAF reading?

Thanks guys, hope to hear some feedback.

[BurrNinja]

Possibly dirty injectors? Next time you do a fill up, run some techron fuel injectors cleaner. I had a bad startup felt like a heavy misfire one time, idle felt a tad rough. I was at 1/4th tank ran techron in and filled up it helped it clear up. I'm going to do a few fill ups using it to see change. Havent bad the rough startup since.

[karim_r]

Originally Posted by BurrNinja

Possibly dirty injectors? Next time you do a fill up, run some techron fuel injectors cleaner. I had a bad startup felt like a heavy misfire one time, idle felt a tad rough. I was at 1/4th tank ran techron in and filled up it helped it clear up. I'm going to do a few fill ups using it to see change. Havent bad the rough startup since.

More of the issue is more than just during start up, since it is only a slight rough idle for less than 3 seconds on start up, however when driven the car does not run as smooth as usual. Shouldn't dirty injectors cause misfire and show up on the misfire counter when checking for smooth running. Will give this a try though once filling up is needed. Thanks

[BurrNinja]

Originally Posted by karim_r

More of the issue is more than just during start up, since it is only a slight rough idle for less than 3 seconds on start up, however when driven the car does not run as smooth as usual. Shouldn't dirty injectors cause misfire and show up on the misfire counter when checking for smooth running. Will give this a try though once filling up is needed. Thanks

As far as I am aware I am not certain, give that a try is my best advice. Perhaps others will be able to chime in.

[karim_r]

Originally Posted by BurrNinja

As far as I am aware I am not certain, give that a try is my best advice. Perhaps others will be able to chime in.

Update: Finally installed the new MAF sensor, it made the car run smoother. MAF sensor values now runs at 14kg/h-17kg/h during idle which is ideal.

However it has not fixed the rough idle on start-up and slight hesitation when accelerating at low speed. Can anybody chime in on this issue?

[TZ]

Plugs and coils?

[n3985]

~50K miles is around when N20 need new engine mounts

[karim_r]

Originally Posted by TZ

Plugs and coils?

Plugs and coils are brand new. Changed them very recently.

[karim_r]

Originally Posted by n3985

~50K miles is around when N20 need new engine mounts

Engine mounts in good condition. But thanks for the info, i will put it on the list for upcoming repairs.

[Hoa]

Try to clean the throttle body

[mashpotato]

And MAP and TMAP sensor.

Reset adaptions on MAF and throttle?

[karim_r]

Originally Posted by Hoa

Try to clean the throttle body

All clean and looks ok.

Originally Posted by mashpotato

And MAP and TMAP sensor.

Reset adaptions on MAF and throttle?

Cleaned both those sensors with CRC MAF Cleaner. I rechecked my spark plugs thinking that it might be injectors, however no fouling on the plugs. I did the reset adaptations after installing new MAF.

The downpipe was taken off and reinstalled, no leaks from the exhaust. Used Redline Fuel System Cleaner and still the same.

The issue still occurs only on a warm engine.

[n3985]

Did you check the vacuum pump seal?

[karim_r]

Originally Posted by n3985

Did you check the vacuum pump seal?

New vacuum pump and seal replaced about 100 miles ago.

[mashpotato]

any signs of leaks? air pipes, vacuum tubes. Valve cover PCV/gasket. Any fault codes still?
Reflash stock and bootmod again?

[karim_r]

Originally Posted by mashpotato

any signs of leaks? air pipes, vacuum tubes. Valve cover PCV/gasket. Any fault codes still?
Reflash stock and bootmod again?

All have been checked and no signs of leak. PCV is brand new, vacuum tubes shows no sign of leak. The car runs fine on a daily basis, just a slight hiccup occasionally on acceleration from stand still as well as rough idle now and then on warm start.

The tailpipes are darker with a lot of black carbon. I doubt its the injectors as the spark plugs look ok.

Will try to bring it in to the workshop this week if time allows. Still open for solutions if you guys have other ideas for me to check.

Thanks all..

[Hoa]

Sounds like your VANOS solenoid might be bad.

[karim_r]

Originally Posted by Hoa

Sounds like your VANOS solenoid might be bad.

UPDATE:

Hi all, an update regarding this issue. A few days ago car went into limp mode (drivetrain malfunction) with the following codes:

118002 : Mixture control fuel-air mixture too rich
130308 : Vanos Exhaust Control Fault, position not reached
120408 : Charging Pressure control switch off as consequence

The workshop erased the fault, however mechanic believes its the timing chain at fault as the car was still occasionally rough running so they kept it to check on the timing chain and found the chain snapped in a few places as he believes that Vanos issues are very rare on the N20.

Not sure if the timing chain issue could be the mixture too rich issue but i will update again once the timing chain replacement is done.
Funny thing was that there was no timing chain noise (rattle or whine), but seeing the condition of the rails, thankful it is attended to before it gotten worse

[alx24k]

Hi, was the problem the timing belt? I am having the same issue for some reason I was told that it was the fuel pump or fuel pump relay... I'm thinking of changing them plus the fuel filter and high pressure pump. Hopefully its not a waste of money.

[Swordsman]

Originally Posted by alx24k

Hi, was the problem the timing belt? I am having the same issue for some reason I was told that it was the fuel pump or fuel pump relay... I'm thinking of changing them plus the fuel filter and high pressure pump. Hopefully its not a waste of money.

What codes are you getting? I'm getting the same codes as the OP after I did the timing chain.

I believe it's either timing or vanos related. I'm also posted over on bimmer forums about this.