I also have a (93) 940 Rex/Regina with lots of miles (434k) In cold weather I have a similar idle problem, and problems with the cruise control. After the engine warms up, both problems go away. I have concluded that it is a couple of hard to find vacuum leaks that seal themselves once the hoses get a little warmer and more flexible.
Kirby J
940 searching idle in cold weather
- regent
- Posts: 1319
- Joined: 22 February 2010
- Year and Model: 2015 XC60 T5
- Location: Under the Hood
- Has thanked: 2 times
- Been thanked: 12 times
Then change those old rotten vacuum lines with some good reliable silicone tubing!

Example of Precision: Measure with a Micrometer, mark it with Chalk, and then cut it with an Axe.
Disclaimer: We (very) seldom do that
2015 BMW 335i
2015 XC60 T5 Premier Plus
2002 S60 2.4 n/a - retired
1987 340 DL - retired
Disclaimer: We (very) seldom do that
2015 BMW 335i
2015 XC60 T5 Premier Plus
2002 S60 2.4 n/a - retired
1987 340 DL - retired
My problem seems to be resolved. No up and down idle this morning! Although it was extremely warm today for this time of year. I would recommend popping off that old idle air motor and giving it a good clean. Use some good spray throttle body cleaner. I also was sure to push the plunger in and out as I sprayed to get it moving smoothly. While you're in there, replace the vac lines that go to it too!
- regent
- Posts: 1319
- Joined: 22 February 2010
- Year and Model: 2015 XC60 T5
- Location: Under the Hood
- Has thanked: 2 times
- Been thanked: 12 times
Glad you sorted it!
Example of Precision: Measure with a Micrometer, mark it with Chalk, and then cut it with an Axe.
Disclaimer: We (very) seldom do that
2015 BMW 335i
2015 XC60 T5 Premier Plus
2002 S60 2.4 n/a - retired
1987 340 DL - retired
Disclaimer: We (very) seldom do that
2015 BMW 335i
2015 XC60 T5 Premier Plus
2002 S60 2.4 n/a - retired
1987 340 DL - retired
-
- Similar Topics
- Replies
- Views
- Last post
-
- 1 Replies
- 607 Views
-
Last post by MoVolvos
-
- 15 Replies
- 2606 Views
-
Last post by volvofornia






