[noshab]

So i own a automatic transmission 2007 bmw 325xi sedan and whenever i am driving the car , the car gives a big jerk when changing gears but it only happens once and all the next shifts are smooth
I , initially thought it was vanos solenoids because i had a code for one of the solenoids too and had it cleaned at a shop but the problem was still there . The car still gives a code for one of the vanos solenoids i.e the exhaust one

The car only gives a jerk in the starting gears i.e when the car shifts from first gear to the second . I had the mechanic drive it for about 10 minutes and he concluded that its not the solenoids or spark plugs and it is actually the transmission and the transmission needed to be repaired/ replaced which is a hella expensive.

I feel like his diagnosis is true and it might be transmission problem but could it be that instead of replacing the whole transmission, it just needs a transmission fluid change or something like that ?
I am asking this because the car is my daily driver and honestly the problem is not that big that it made it undriveable . I am literally driving it everyday . Apart from that first gear shift and rarely rough idling , the car seems to be fine .
I also feel like it might be actually the solenoid and i should replace it first before doing anything else to the transmission
Are there any other symptoms that could maybe pinpoint if it actually is the transmission problem itself or just the fluid or something. I got the car like 2 months ago and don't want to drop a ton of cash on a new transmission

[noshab]

Anybody got any clue ?

[noshab]

I can't believe no one's got any clue about this

[F31B48]

Originally Posted by noshab

I can't believe no one's got any clue about this

Are there any fault codes stored in any modules?

[relative4]

Well for starters, you haven't mentioned how many miles are on the car or the fluid, or if the transmission is a GM or a ZF.
In general, the most common culprit is the double square seal. Your starting point is to replace the pan / filter, fluid, and all seals.

[noshab]

Originally Posted by EvaBmw

Are there any fault codes stored in any modules?

- 2E98 (current). BSD, communication; generator: absent

- 2A87 (history). DME: VANOS (release), mechanism
- 2E81 (history) DME: Electric coolant frequency control time.
- 2E85 (history). Binary code serial data interface, message; electric coolant pump: none



Also i have the 4x4 , ABS , traction control light on the dash . The mechanic said it is due to the white VTG Module

[relative4]

1. Address the alternator/BSD issue. Unplug one BSD consumer at a time till the other 3 work normally. Then you've found your culprit.
2. Address the trifecta. Most common cause is a wheel sensor or associated reluctor issue. Strange there are no codes for that. How did you pull codes?
3. Address theVANOS solenoid. Swap the solenoids and see if the code moves.

[lookalikehuuh]

Originally Posted by relative4

1. Address the alternator/BSD issue. Unplug one BSD consumer at a time till the other 3 work normally. Then you've found your culprit.
2. Address the trifecta. Most common cause is a wheel sensor or associated reluctor issue. Strange there are no codes for that. How did you pull codes?
3. Address theVANOS solenoid. Swap the solenoids and see if the code moves.

I totally agree with this. Plus WTF you are chasing a jerky transmission with a christmas tree of stuff lit up on the dashboard. This makes my OCD go crazy.

Anyway not sure what transmission your car has but the ZF transmissions are known to have leaky internal seals/sleeves that can cause shifting problems due to pressure loss. Once all the other issues are addressed this might be a good way to go, I believe there is a way you can read the current transmission adaptations to see if the adaptations are on the higher range it points to the seals/sleeve issue.

[noshab]

Originally Posted by relative4

1. Address the alternator/BSD issue. Unplug one BSD consumer at a time till the other 3 work normally. Then you've found your culprit.
2. Address the trifecta. Most common cause is a wheel sensor or associated reluctor issue. Strange there are no codes for that. How did you pull codes?
3. Address theVANOS solenoid. Swap the solenoids and see if the code moves.

1). It might be a dumb or noob-ish question but how do I address this BSD issue ? Like what am I supposed to unplug and from where?

2) the shop that i had my car checked at said it was the VTG module problem (the white module i posted in the pics ) . Its disconnected right now anf kept in the trunk by me until i find a replacement module .

[noshab]

Originally Posted by lookalikehuuh

I totally agree with this. Plus WTF you are chasing a jerky transmission with a christmas tree of stuff lit up on the dashboard. This makes my OCD go crazy.

Anyway not sure what transmission your car has but the ZF transmissions are known to have leaky internal seals/sleeves that can cause shifting problems due to pressure loss. Once all the other issues are addressed this might be a good way to go, I believe there is a way you can read the current transmission adaptations to see if the adaptations are on the higher range it points to the seals/sleeve issue.

Lol yeah , there a ton of lights on the dash right now and they are gonna stay on until i replace the VTG Module ( white module in the pics ) .
Yeah I'll get the transmission checked by a mechsnic pretty soon . Lets see what the problem comes out to be

[andrew2cu]

I had the same issue on my 2011 328i but my issue was accompanied by a rough idle and my issue was the cage part of my oil filter cap was broke off from a previous owner. Might not be your problem but doesn’t hurt to check.

[noshab]

Originally Posted by andrew2cu

I had the same issue on my 2011 328i but my issue was accompanied by a rough idle and my issue was the cage part of my oil filter cap was broke off from a previous owner. Might not be your problem but doesn’t hurt to check.

Well I do get a bit of a rough idle occasionally for a couple of seconds but it goes away on its own but yeah it doesn't hurt to check
Thanks for the suggestion 🙂

[csquared013]

Originally Posted by noshab

Lol yeah , there a ton of lights on the dash right now and they are gonna stay on until i replace the VTG Module ( white module in the pics ) .
Yeah I'll get the transmission checked by a mechsnic pretty soon . Lets see what the problem comes out to be

If I were you and the transmission hasn't been serviced in a while I'd start with a fluid change and mechatronics sleeves like was said in here. Easy job if. Solenoids are right there too if you wanted to change them.

[noshab]

Originally Posted by csquared013

If I were you and the transmission hasn't been serviced in a while I'd start with a fluid change and mechatronics sleeves like was said in here. Easy job if. Solenoids are right there too if you wanted to change them.

Yes i am thinking of getting the one solenoid replaced which is giving the error . After that if the problem still persists, I'll go for the transmission fluid change and lets see what happens . Thanks for the advice

[relative4]

Yer gonna replace a tranny solenoid without draining the fluid? Awesome, please let us know how that goes.

[noshab]

Originally Posted by relative4

Yer gonna replace a tranny solenoid without draining the fluid? Awesome, please let us know how that goes.

I was talking about the Vanos solenoid bruh