N42 Valvetronic Vibrations.....
- Thread starter beem
- Start date
yendor
Well-Known Member
Re: N42 Valvetronic Vibrations.....
Valvetronic engines have no throttle plate and thus have no idle valves. So got nothing to clean in the intake. It is the intake valves in the combustion chamber roof that can develop deposits which screws up the idling.
Since you tried swapping the coils and plugs, i suspect a dirty intake valve or dirty injectors. Do the exercise that i mentioned before. It may clear the problem...
Cheers
beem;135693 said:
Valvetronic engines have no throttle plate and thus have no idle valves. So got nothing to clean in the intake. It is the intake valves in the combustion chamber roof that can develop deposits which screws up the idling.
Since you tried swapping the coils and plugs, i suspect a dirty intake valve or dirty injectors. Do the exercise that i mentioned before. It may clear the problem...
Cheers
Re: N42 Valvetronic Vibrations.....
I would check the color of the spark plugs to see if there is any problem with the mixture...if it's rich the lambda sensor needs replacement. A faulty MAP sensor will also cause an erractic idle however it will also likely affect the power, have it checked.
The poor compression in one of the cylinders may be due to carbon build-up at the valve seat/face preventing proper seating/sealing, not uncommon on cars doing short or occassional runs. As suggested, a bottle of 'injector cleaner' and a spirited run on the NS hywy will help.....
I would check the color of the spark plugs to see if there is any problem with the mixture...if it's rich the lambda sensor needs replacement. A faulty MAP sensor will also cause an erractic idle however it will also likely affect the power, have it checked.
The poor compression in one of the cylinders may be due to carbon build-up at the valve seat/face preventing proper seating/sealing, not uncommon on cars doing short or occassional runs. As suggested, a bottle of 'injector cleaner' and a spirited run on the NS hywy will help.....
Kenzo
Well-Known Member
Re: N42 Valvetronic Vibrations.....
i had similar problems w my previous e46.. felt like ppl shaking the car from outside..
changed many things, but the ones that worked for me, ironically, were:
1. Changing to 95 petrol (not so jerky)
2. Not using auto aircon function and keeping aircon power around half bar..
not exactly sure why, but i suspected the solar thermostat and the a/c compressor were the culprits..
good luck in ur troubleshooting!
i had similar problems w my previous e46.. felt like ppl shaking the car from outside..
changed many things, but the ones that worked for me, ironically, were:
1. Changing to 95 petrol (not so jerky)
2. Not using auto aircon function and keeping aircon power around half bar..
not exactly sure why, but i suspected the solar thermostat and the a/c compressor were the culprits..
good luck in ur troubleshooting!
beem;135693 said:
martmode8850
Well-Known Member
Re: N42 Valvetronic Vibrations.....
thanks SL2... checked my free oil given by PML when i took the car... it's 0W-40... guess it's the same as 5W-50 but at different operating temperatures???
SL2;134841 said:
thanks SL2... checked my free oil given by PML when i took the car... it's 0W-40... guess it's the same as 5W-50 but at different operating temperatures???
beem
Well-Known Member
Re: N42 Valvetronic Vibrations.....
Dun think there's a carbon filter in my car bro...
Latest update...after a rough running cylinder cycle check...the fourth cylinder came up above the specifications...however, when the engine cooled...the mech took out the spark plug and found oil around the plug...cleaned the plug from oil...put the plug back in...voila...the car is as smooth as a 6-potter....but...after leaving the car to heat up...damn...the vibration came back....again the rough running cycle check showed the fourth cylinder is marginally out of specification....took out the plugs again..no oils....mech suggested a leak test.....
I was wondering if there's anything on the fourth cylinder that could be causing a leak..hence vibration, more so when the car is hot.....is there a ring or something on the spark plug?
Dun think there's a carbon filter in my car bro...
Latest update...after a rough running cylinder cycle check...the fourth cylinder came up above the specifications...however, when the engine cooled...the mech took out the spark plug and found oil around the plug...cleaned the plug from oil...put the plug back in...voila...the car is as smooth as a 6-potter....but...after leaving the car to heat up...damn...the vibration came back....again the rough running cycle check showed the fourth cylinder is marginally out of specification....took out the plugs again..no oils....mech suggested a leak test.....
I was wondering if there's anything on the fourth cylinder that could be causing a leak..hence vibration, more so when the car is hot.....is there a ring or something on the spark plug?
oneHeadlight
Well-Known Member
Re: N42 Valvetronic Vibrations.....
I am no expert but after i changed the mounting...the vibration disappeared.
I am no expert but after i changed the mounting...the vibration disappeared.
