Need Advise: E39 Engine Vibrate

[BMW2007]

Hi, noticed that the car has a bit of vibration when start up the engine in cool temperature. The symptoms disappear after ~1 min engine warmed up. Anything wrong or it si norm? thanks

 

[IsaacVky]

cold start. I think its normal.

 

[BMW520]

I have the same experience too... It is a norm for all BMW??

 

[conan]

I have the same experience too... It is a norm for all BMW??

it's not "normal" but "common" for older engines..

 

[BMW520]

it's not "normal" but "common" for older engines..

M54 engine consider older engine? not really expert on the engine stuff

 

[Jerman]

M54 engine consider older engine? not really expert on the engine stuff

M54 should be considered as new engine. Have you tried checking the engine mounting, spark plugs or injectors?

 

[BMW2007]

Jerman, the vibrate happen during the engine startup and car in idle when the temperatiure is still cold. Once it warmed up for about 1 min, it is so stable.. dont feel the vibrate when driving.. spark plugs had just been changed. Not sure the mounting could really cause it, but the car is stable/smooth when driving or after engine heat up.

 

[paultantk]

I doubt this is normal behaviour for M52/M52TU/M54.

 

[bmw7833]

Check the ignition coil, bro.

 

[bimmerholic]

Did it sound like misfiring during that ~1min you mentioned?

 

[BMW2007]

holic.. what could cause the misfiring? Just chnaged the spark plugs 4 momths ago.. did not seen any other thing except vibrate. The car is stable after warm-up

 

[leforte]

check the engine compression pressure. your engine bore may have be worn. or possibly a nikasil issue... what year is your car,? other than that , there is a possibility that the piston rings may be stucked and its causing a low compression at cold start but it expand or loosen up when the engine and oil warms up.

 

[BMW2007]

M54 '02, dont think it is nakasil issue. BTW, what should be the right RPM when engine idle at cold start?? Please advise.

Noticed that the rpm is ~800-900 at cold start in the morning, that is where the vibration happened. When slightly press the right foot to increase the rpm to 1000-1200, dont feel the vibrate at this rpm. The vibration disappear within 30 sec of startup and the temperature is now showing at the 1st bar (blue color bar), the car is stable at ~700 rpm.

 

[bimmer73]

nope cannot be coil nor the engine mounting. I have new engine mountings and ignition coil. could be injectors but i doubt it my be a little moist in the engine.

 

[BMW2007]

bro, what is the correct rpm reading during cold start (when engine started)? suspect the rpm might be a little bit low (800~900) during cold start, should it be 1000 or above? tq

 

[bimmerholic]

bro, what is the correct rpm reading during cold start (when engine started)? suspect the rpm might be a little bit low (800~900) during cold start, should it be 1000 or above? tq

mine's very close to 1K

 

[bimmer73]

It should be close to 1k

 

[akj0711]

I had the problem solved when I replaced the idler valve and pressure valve.

 

[BMW2007]

Thanks Bro. So looks like the rpm have to increase a bit..to 1k when the engine 1st startup from cold. How to adjust the rpm for cold start? is it programmable?

akj0711, do u notice your car rpm change/increase during cold start after replaced the idle valve and pressure controllers?
btw, how much the idle valve and pressure valve costs? tq

 

[champion]

My rpm is at around ~900 during cold idling.