Underpowered During Take Off..

[Bimmer883]

Hi all.. Need some advise please. My M52tu 523i is sluggish at times especially during take off. Its really under powered at times but this does not happen always? Just got it serviced recently and nothing is popping out in the scanner. Mech claims it very hard to trouble shoot unless it happens while testing. Pls advice. Many thx..

 

[rizaljai]

Suspect your Vanos seals need replacement.

 

[wingzee]

Yea bro might be your VANOS seals. What's your milleage? Replaced mine at 180,000km and low-end is so much better now.

 

[Bimmer883]

Thx guys. My mileage is 283,000 plus2 now. Previous owner changed it bout 150,000km before. Any other reasons that can contribute to this issue? Problem is, it doesn't happen all the time. Probably about 50% of the time during driving daily

 

[Psykit]

Bimmer883 bro, can you describe more on the feeling of the underpower and when will it occur? Do you notice any particular environment or condition? Does it happen only during cold or engine full warmed up? Any particular gear? 1st gear only? Does it happen during hard acceleration when you floor the pedal?

 

[Bimmer883]

Bro Psykit, its happens in no particular environment or condition. Also, it sometimes happens during cold start but mostly after engine fully warmed up but definitely noticeable during hard acceleration when u need to overtake somebody or come out of a junction. Gearing would be between 1-3 I think.

 

[gendong]

Bro, apart from the items that were mentioned above, when was the last time you changed the air filter? Do a visual inspection.......

 

[seewai]

Apart from above recommendations, do have torque converter and auto gb checked too.

 

[Bimmer883]

Bro gendong, I will check my filter again. Thx for the advise..

Bro Seewai, u might be right there too. Where can I get my torque converter or auto gb checked? Does this means I have to take down the gearbox or is there an easier way to check

 

[tweiboon]

Bro gendong, I will check my filter again. Thx for the advise..

Bro Seewai, u might be right there too. Where can I get my torque converter or auto gb checked? Does this means I have to take down the gearbox or is there an easier way to check

If really a gearbox issue better do it fast before it become worst. The worst case of gearbox needs to spend RM7k or above for rebuild gearbox.

 

[Bimmer883]

Problem is the previous owner which is a close fren just spend about 7k to rebuild this gearbox. Not sure bout the torque converter though..

 

[Bimmer883]

Post deleted..

 

[Bimmer883]

Problem Solved.. Turns out the culprit is the camshaft positioning sensor that is causing the lack of low end power.. Ended up with a pretty big hole in my pockets though in my quest to solve the problem.. Replace a few other things too along the process.. List below..

Power Related Items:
- Engine Oil / Filter - Done
- Gearbox Oil / Filter - Done
- Fuel Filter - Done
- K&N Filter - Done
- Ignition Coils x2 - Done
- Spark Plugs x6 - Done
- Camshaft Positioning Sensor (exhaust) - Done
- Vanos Seals / Rattling Kit - Done
- LM Jetclean - Done

Other Items:
- Expansion Tank - Done
- Expansion Tank Hoses x2 - Done
- Radiator Hoses x1 - Done
- Water Pump - Done
- Waterpump Housing - Done
- Fan Belt - Done
- ABS Rear Sensor - Done
- UR Strut Bar - Done
- UR Rear Arb - Done

Next to do list:
- Front Arb
- Electric Fan Conversion
- M5 bodykit
- Paint Job
- Exhaust system with quad tail pipes
- Proper Shocks
- Better Brakes
- 3 spoke steering
- And the list goes on..

 

[wingzee]

Glad you're able get it solved bro. Just wondering how did you or your mech determine that camshaft positioning sensor is the culprit? Is it via a computer diagnostic test?

 

[Bimmer883]

Glad you're able get it solved bro. Just wondering how did you or your mech determine that camshaft positioning sensor is the culprit? Is it via a computer diagnostic test?

Thx bro.. The diagnostic machine could not detect it but since I had my Vanos seals replaced, told mech to check the sensors as well as i read in bimmerforum this sensor could be the issue.. Turns out there's a small hairline crack on the sensor and some engine oil is seeping thru it. The sensor is still working but not at its optimum hence the occasional power lost..

 

[insomniac]

I have a 3-spoke steering available.


Let the racuning begin!!

 

[Bimmer883]

Hahaha.. No budget yet bro.. Need to fix Bodykit and Paint Job first. Btw, how much u selling? If cheap2.. Maybe can consider then..

 

[huskar3399]

how much is the cp sensor?

 

[insomniac]

Hahaha.. No budget yet bro.. Need to fix Bodykit and Paint Job first. Btw, how much u selling? If cheap2.. Maybe can consider then..

I've sent you a PM

 

[JFT63]

how much is the cp sensor?

About 250 or so...replaced mine last year...