DIY: Idle Control Device / Valve and Tubing

OMRITIME wrote

When cold start my engine idle keep bouncing , almost shut the engine off I'm "helping" the car with my foot on the gas pedal keep it on 1500rpm few seconds (20 sec) until the cold start ends
Do I need to replace this part or the actuators

(Always have this problem when the car parked few days....and only at the first start)
Thanks

Hi there, I know it has been a while but how did you solve the problem? I am having exactly the same issue as yours but a little more frequent—almost every complete cold start, the rev bounces and usually ends up in limp mode. I replaced my throttle actuators with two rebuilt ones. And I haven't replaced my idle control valve. Id like to say that the idle control valve is falling or the rebuilt ones that I have on right now need to be replaced again.

dylansun wrote

Hi there, I know it has been a while but how did you solve the problem? I am having exactly the same issue as yours but a little more frequent—almost every complete cold start, the rev bounces and usually ends up in limp mode. I replaced my throttle actuators with two rebuilt ones. And I haven't replaced my idle control valve. Id like to say that the idle control valve is falling or the rebuilt ones that I have on right now need to be replaced again.

PM me. The codes you are getting.

Sorry for reviving an old thread but I am curious.
Why do our cars have an Idle Control Valve?

With older cars that had mechanical throttles, I understand that this was necessary to have computer control over engine idle speeds, but on modern cars with throttle by wire, why is this necessary?
Clearly the ECU has complete control over the throttle butterfly valves, otherwise we would not be able to use Cruise Control.

GtiGyver wrote

Sorry for reviving an old thread but I am curious.
Why do our cars have an Idle Control Valve?

With older cars that had mechanical throttles, I understand that this was necessary to have computer control over engine idle speeds, but on modern cars with throttle by wire, why is this necessary?
Clearly the ECU has complete control over the throttle butterfly valves, otherwise we would not be able to use Cruise Control.

Just going on speculation, but probably hard to control idle on ITBs with the large surface area across the multiple throttle plates. And linked to that, managing idle over a small area of the actuator gears would wear them out more than they already do!

I don't want to start a new thread on this topic.

Can someone please confirm:

My engine went into limp home a few weeks back on cold start, and it happened again the other day. Same codes as the first time that lead to Idle Control Valve.

I bought a new fuel breather valve, but decided against buying an idle control valve figuring I can clean it out.

Back in the day when I owned an e36 m3 some 12-15 years ago, this was also a common problem however the solution was cleaning it out with carb cleaner or soaking it in sea foam - I forgot which product it was exactly. But you could clean it out, which would typically resolve the issue.

For the e92 m3, I searched the codes I was getting and from what I found - everyone that has had this issue has replaced the entire ICV unit. Why not clean it? Does that not work or am I missing something? Obviously trying to avoid spending $800 if I don't have to.

GinTonic wrote

I don't want to start a new thread on this topic.

Can someone please confirm:

My engine went into limp home a few weeks back on cold start, and it happened again the other day. Same codes as the first time that lead to Idle Control Valve.

I bought a new fuel breather valve, but decided against buying an idle control valve figuring I can clean it out.

Back in the day when I owned an e36 m3 some 12-15 years ago, this was also a common problem however the solution was cleaning it out with carb cleaner or soaking it in sea foam - I forgot which product it was exactly. But you could clean it out, which would typically resolve the issue.

For the e92 m3, I searched the codes I was getting and from what I found - everyone that has had this issue has replaced the entire ICV unit. Why not clean it? Does that not work or am I missing something? Obviously trying to avoid spending $800 if I don't have to.

Like you I’ve not heard or read of anyone cleaning the ICV to restore its functionality. I say it’s worth trying and reporting back with your technique and findings (results). If cleaning the ICV doesn’t work then that’s worth knowing. If it does you’ve saved $800. It’s definitely worth a try.

I figured its worth a shot and worth the extra hour of work. If it doesn't work, at least I tried. I'll report back.

GinTonic wrote

I figured its worth a shot and worth the extra hour of work. If it doesn't work, at least I tried. I'll report back.

Did you get around to doing this yet? I think my ICV is failing and I’m debating whether to clean it or replace. I have 33k miles on my 2013

I recently experienced P152D Manufacturer Control from my OBD II scanner and with ProTool it is 2B0D Idle Actuator Monitoring, Bank 1. My throttle actuators were replaced less than 1,500 miles ago.
In process of replacing the FBV (Fuel Breather Valve) and the ICV (Idle Control Valve). FBV was easy to remove, but the ICV I can see is a bit more challenging. More to come on the resutls and if it has fixed my idling problem between 2K and 2.5K RPM's that is consistently happening at startup.

2008 BMW M3 Active Autowerke SC Manual. 106K and the video of the cold start issue can be found on YT when you search 2008 BMW M3 S65 Active Autowerke Idling Issue before fix

Sub’d, having same issue on cold start, get P152D error code, limp mode…

GinTonic wrote

I figured its worth a shot and worth the extra hour of work. If it doesn't work, at least I tried. I'll report back.

Did cleaning it work?

DrFerry wrote

Did cleaning it work?

I never did it. I bought an Epic tune in May and the issue went away.

DrFerry wrote

Did cleaning it work?

So, coming back to this.

The symptoms came back about a month or two ago with the colder weather. It was really noticeable when putting the car into gear right after starting the engine.

Since I had the plenum off the other day, I changed out the fuel breather valve. I ordered one a year ago and never got around to changing it out. All symptoms of fluctuating idle are now gone.

Has anyone succeeded in ICV cleaning?

I haven’t seen any reported successes. Only lots of reports early on in the life of these cars showing failures of the idle control device and dealer replacements. Mine hasn’t failed or tested poorly but it definitely makes almost a digital sounding chirp during cold starts that goes away when the idle drops down to low idle. I don’t know if cleaning would do anything for me but the unit definitely sounds odd. I’ve verified that it is the idle controller with a stethoscope.

spammysammich wrote

I haven’t seen any reported successes. Only lots of reports early on in the life of these cars showing failures of the idle control device and dealer replacements. Mine hasn’t failed or tested poorly but it definitely makes almost a digital sounding chirp during cold starts that goes away when the idle drops down to low idle. I don’t know if cleaning would do anything for me but the unit definitely sounds odd. I’ve verified that it is the idle controller with a stethoscope.

Was this the chirping noise you was on about?

Didn’t have noise before but I had a code for idle control valve. Changed for new one as well as fuel breather. Put back together again now I have no codes but I have this noise now. Didn’t have the noise before.

Also do I need to reset adaptations for idle control valve and fuel breather

zacrrich wrote

Was this the chirping noise you was on about?

Didn’t have noise before but I had a code for idle control valve. Changed for new one as well as fuel breather. Put back together again now I have no codes but I have this noise now. Didn’t have the noise before.

Also do I need to reset adaptations for idle control valve and fuel breather

Yes. Exactly the same but it goes away when the idle drops down to low. I stopped trying to hunt it down. It is what it is.

Managed to get mine on video, yes mine too drops when idle is low. Hopefully BMW will replace my faulty ICV I chnaged on Friday.

jnijni wrote

Has anyone succeeded in ICV cleaning?

Yes, I believe CamasM3e93 successfully cleaned his ICV.

DrFerry wrote

Yes, I believe CamasM3e93 successfully cleaned his ICV.

I did. Not sure if it did anything but I cleaned away 150k miles of hard carbon material along the valve seat. I tried a throttle body cleaner with a cotton tip but ended up needing to scrape with a dental pick. The valve body doesn’t budge so it’s hard to get a perfect clean immediately beneath the body where it seats into the wall