DIY rough idle fix

[tomgtv]

I have a 2001 3.0L X5 with 195,252 miles. Lots of repairs and $$$
so I"ve gotten more into fixing it myself. These sites are great, have
saved tons of $$$. Many of the repairs are so simple that you owe it
to yourself to learn a few.

I started to have a rough idle. Looked all over for info and advice and
this site suggested idle control valve may be broken or needs cleaning.
So with the excellent pix from DIY article I started the job.

Slight detail. First step is to remove the black box which I later find out
is called the "Adjuster". It has one electrical connection and two easily
accessed torx screws. When I removed the screws the unit would only
come out an inch or so. I twisted every way thinking this was another
one of those "secret elf" things that BMW does with parts removal. No Go.
So figuring it was supposed to come out no matter what I resorted to
brute force.........pow, snap, crack.......it came out in pieces!

Turns out the offender is a butterfly valve that I surmised had broken off
it's shaft and was out of the U shaped holder. By forcing it I broke the
top yoke and it came out.

Went to BMW this am, idling rough, but OK at speed. $277 for part, put it on in
the parking lot........maybe 2.7 min...........and wha la! Smooooooooooth
idling, just like a BMW......

The parts counter guy was impressed that I was able to diagnose this. Says
they sell a lot to indy garages and their own use. BMW dealer cost for diag, labor and
part? About $800..........

[amcink]

Good job

[upoyX5MR2]

so how do you carefully remove it?

[X5Dawg]

Good job - got a few questions. My '01 has about 143K miles on it and I have experienced some rough idling too, but not all of the time. What RPM were you iddling at before/ after the fix?? Also, I notice mine more when the A/C is running - was this the same for you?? My rough idle is not like a rattling or shaking, but more like a surging - can you describe how yours was running???

Thanks again for the info!!

[X5Dawg]

????

[tomgtv]

Originally Posted by upoyX5MR2

so how do you carefully remove it?

It will just pull out if it is not broken after you remove the 2 torx screws
and unhook the electrical connection (by squeezing silver clip on the
base next to motor).

My idle was rough as in vibration. My tach stayed still, so no RPM's.
Once I got any speed went away. BUtterfly valve must have stuck
in some intermediate position.

2nd Possibility - a year or so ago I got the dreaded replace the Air
Mass Sensor when I experienced rough idle also. $425 for part and $85 to
install. FYI, the install is the easiest thing you will ever do, two clips and
1 elect connector and its done. IT's right on top of motor on the way
from air filter to manifold.
The real fix?? !! One of my Jetski buddies gave me this tip, shoot
a carb clearner into the thin plastic fitting which contains the sensing
element. Unhook from air filter and just blast it. It worked! So the second
time I saved over $500!

[sawastea]

I just had my truck overheat and had the coolant reservoir replaced as well as the shift link. I was driving it today and it was fine on the highway until I got onto the backroads. The 'check engine soon' light came on and there was rough idling and very little power when I was driving. Having AAA come by to pick it up. Possibly relate to the above?

[X5Dawg]

Originally Posted by tomgtv

2nd Possibility - a year or so ago I got the dreaded replace the Air
Mass Sensor when I experienced rough idle also. $425 for part and $85 to
install. FYI, the install is the easiest thing you will ever do, two clips and
1 elect connector and its done. IT's right on top of motor on the way
from air filter to manifold.

Bingo - just had this replaced last week along with a throttle valve.