Wierd diesel like sound and low idle+shudder

[apathy11303]

Hello all... So I have had this 330i 6spd for about 3 weeks now... The other day, it began to idle low around 600rpm + which causes the car to shudder as if it wants to die... If I hold the gas pedal and make it stay around 750-800rpm, the shudder goes away and all sounds fine--but I have to hold the gas pedal to keep it there...

Also, it began making a clicking diesel like sound... After searching the forum, I decided to try cleaning the ICV and inspecting the DISA... The flap on the DISA was completely broken and was sitting free inside the compartment. So, I removed the flap and put the DISA back in and now the "diesel like" sound is gone...

Is it ok to leave the DISA like that (w/o the flap) or create a block-off plate like I read during previous searches?

I also cleaned the ICV using brake parts cleaner and reinstalled it... Now the car revs smoother and accelerates a bit better, but still has a low idle + shudder...

I have not tried cleaning the MAF yet because I dont have MAF cleaner right now, but it looked pretty clean when I looked at it (I didnt see any gunk or buildup on it.)

What else could I check out to resolve the low idle issue...

I appreciate any advice and I thank you all for your time...

Also, the intake boots looked fine upon inspection, so I do not believe they need to be replaced...

[slvrXI]

There is a metal pin long, that the disa flap is hinged on to. Did you recover that pin? It should be fine otherwise, with slight performance decrease and mixture adaptation faults. If you did not recover the pin, it is not safe to drive, it can make its way into the intake manifold and possibly damage a valve.

Low idle can be fixed with bmw software>service functions>idle speed adjustment. However a shudder or vibration is bad at 600 rpm, it should be smooth. First check the fault codes stores in DME, do you have service engine light illuminated? Misfires will cause shudder/vibration. Then check engine and transmission mounts for wear/play. Next inspect belt drive and pulleys. Lastly check dual mass flywheel for wear/out of balance.

Remember engine vibrations can be dangerous! Nuts and bolts can become loose and un fasten. Oil pump sprocket is most common and will cause oil starvation-destroyed engine.

Good luck

[apathy11303]

Ok... I will remove the DISA again to check on the pin... I do not remember seeing one... Thanks for the heads up... I do not want to cause anymore issues...

[slvrXI]

This may help, googled it.

http://forum.e46fanatics.com/showthread.php?t=830557

[apathy11303]

Wow... I just removed the DISA again and fished around in there for about 20min with a magnet... I didnt find anything though... I hope all will be ok with that...

On another note--the driver's side motor mount does appear to be wet, when everything else in the engine bay is dry... If this vehicle has liquid filled motor mounts, I suspect the mount needs to be replaced as well as it appears to be leaking...

[slvrXI]

Drivers side may be wet due to oil leak- oil filter housing gasket. Remember, when one mount needs to be replaced, it is strongly advised to replace all mounts due to the excessive play of the engine/trans assembly. Both left and right motor mounts as well as left and right trans mounts.

[apathy11303]

Yea. I was thinking about buying a full set (motor+tranny mounts...) This seems like a fun DIY... I dont think it is motor oil b/c it is more of a clearish-jelly type substance...

Also, I bought some MAF Cleaner and now the car appears to be running smoother, not missing... So now I just need to change the mounts... Thanks for the help...

[slvrXI]

Glad we were able to help. Its always nice when the forums produce accurate, quality information. Rather than misleading incorrect crap that circulates this place.

Cheers!

[apathy11303]

Hey all, I know this is an old thread, but I never really said what resolved it fully. It turned out to be a Vanos issue (the seals were shot and the exhaust piston was stuck--#4 in photo). So I did a besian kit overhaul and used a dremel to smooth out the cylinder where the piston went + replaced the piston.



Talked about it a bit more here: https://www.bimmerforums.com/forum/s...ngine-failures