Quote:
Originally Posted by slowblackx3f25
Quote:
Originally Posted by ClampThurst
I've had this on my X3 2017(73,000 miles) N55 motor as well(even posted on here about it and noone had any good input on it). It used to do it a bunch and one day I disconnected the batter power for one minute and it went away but is now back after a few months. I am getting an "under voltage in vehicle" computer code (4809AB) not sure why, might be a drop in voltage while starting. Also getting a "ZGM central fault memory full-no control unit fault"(801C20) Not sure if these are related to the idle problem. Mine ranges from 700-1000 RPM at street light after stopping. Have you noticed if it does it in manual gear select mode??? Mine did not, the RPM variations only occurred when coming to a stop in automatic transmission mode only. It occurs with Climate control on and off.
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No I haven't checked while in manual gear box mode. I'm always in automatic gearbox mode.
I'll check if it does it in manual gear box mode.
The RPM's will only jump up and down at a full stop, or while in heavy traffic. It doesn't happen often though…
I was driving the x3 last night and it was fine. RPM stable at every red light/full stop in traffic.
Once I let go of the brake pedal, RPM comes back to normal reallll quick.
It accelerates fine and puts down power all the way through each gear/RPM band without any hesitation.
So I doubt it's fuel injectors.
Sometimes no one will answer and we got to figure it out by ourselves |
Quote:
Originally Posted by slowblackx3f25
Quote:
Originally Posted by ClampThurst
I've had this on my X3 2017(73,000 miles) N55 motor as well(even posted on here about it and noone had any good input on it). It used to do it a bunch and one day I disconnected the batter power for one minute and it went away but is now back after a few months. I am getting an "under voltage in vehicle" computer code (4809AB) not sure why, might be a drop in voltage while starting. Also getting a "ZGM central fault memory full-no control unit fault"(801C20) Not sure if these are related to the idle problem. Mine ranges from 700-1000 RPM at street light after stopping. Have you noticed if it does it in manual gear select mode??? Mine did not, the RPM variations only occurred when coming to a stop in automatic transmission mode only. It occurs with Climate control on and off.
|
No I haven't checked while in manual gear box mode. I'm always in automatic gearbox mode.
I'll check if it does it in manual gear box mode.
The RPM's will only jump up and down at a full stop, or while in heavy traffic. It doesn't happen often though…
I was driving the x3 last night and it was fine. RPM stable at every red light/full stop in traffic.
Once I let go of the brake pedal, RPM comes back to normal reallll quick.
It accelerates fine and puts down power all the way through each gear/RPM band without any hesitation.
So I doubt it's fuel injectors.
Sometimes no one will answer and we got to figure it out by ourselves |
Hi all,
I finally got around to resolving the RPM fluctuations in my dad's x3 2017 N20 motor.
It was the transmission that needed to be updated. I got it reprogrammed at 313 Motorworks in Mississauga ,Ontario, Canada.
Khalid and his 313 team did an amazing job and fixed the RPM fluctuations by reprogramming the x3 transmission.
It was outdated according to 313. The x3 drives so much better now. No lag, no jerks, no issues at all. The RPM needle doesn't jump up and down while at a full stop in gear D.
The updated transmission programming fixed it!
At least for my dad's x3. Happy I got it fixed.
Anyhow, sorry for the long rant. This is how I fixed the RPM fluctuations/RPM jumps/RPM hang whatever you wanna call it.
Sometimes it can be Ignition coils, spark plugs, carbon build up, PCV, but I got these components checked and no CEL so it came down to transmission programming and so I got it reprogrammed.
I was also told it can be the timing chain but I had that checked by 313 Motorworks. Timing chain is good on the 2017 N20 motors.
Let's keep all our BMW's running strong and lubricated
Take care guys. I hope this helps.