Idle

[Heinrich]

Hi everyone. Please listen to this:



When just starting there is no problem. When warm no problem either. So between start and full temp. it runs up and down when ideling. When speeding up it's like not all cyl. are comming along at the same time.

Any idea what it coursing this?

[Jeroen]

Could be a vacuum leak, but in most cases a incorrectly adjusted CO is the cause. You just did a long trip and that may have had its influence (cleaned things up). Have the CO checked, make sure it's in the 1.5-2.5% range and usually that solves the issue already.

[Heinrich]

Thanks, will try that at first. Where is the adjustment screw placed?

[Peter V.]

http://bmwfans.info/parts/catalog/E21/S ... ow_sensor/

Under the number 5 cap is a hole. Here the adjustmentscrew is located. (Most likely will not find the cap anymore and it is just a hole).

[Heinrich]

Thanks Peter,

Found it, but what kind of screw driver is needen? Don't seem like it's a normal flat one?

Rgds.

[Peter V.]

It's a 3 mm allen (google translate????)

[Heinrich]

Here we call it Umbraco, so I did understand

Thanks to both of you!

Rgds.

[Peter V.]

Here we call it Umbraco, so I did understand

Thanks to both of you!

Rgds.

So i could better said it in Dutch then "Imbus".

Good luck with it.

[Heinrich]

Since I don't have licensplates on the car yet, I can't go to a garage to have the CO ajusted. They took a test when I was at the MOT. It was only 0,6-0,7. I just tryed to adjust the screw a little and it is VERY sensitive. Even by touching the screw the engine changes performans and sound. First adjusting one 1/4 and it ran fine again. Then only by touched the imbus it started to rool again. Should it be that sensitive or do I miss a gasket or something?

[Jeroen]

Nope, they are that sensitive. You can make it run a bit better using just your hearing now but it needs a CO/exhaust gas analyzer and a steady hand haha

[Peter V.]

Make sure you turn the screw just a little bit. 1/4 is a big adjustment already.

When you measure it remove the umbraco because the weight alone is enough to give the wrong figures.

[Heinrich]

Can anyone tell me where I adjust the idle speed?

[Jeroen]

Big brass screw on the throttle body

[Heinrich]

And 750/800 rpm.?

[Peter V.]

850 to 900 rpm