The message to which you are about to reply is shown first. GO TO REPLY FORM



 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

engine shudder after cold start S90-V90

One way that vacuum causes bad fuel mileage: engine vacuum is used to control a lot of little valves under the hood of your car. PCV, ICV, EGR, Trottlebody stuff, fuel pressure regulator, power brake booster, etc. Heck, even the flaps in your AC vents that dictate whether the air blows on your feet, face, or windsheild are vacuum driven! Every leak removes some pressure and causes those valves to respond more slowly. Once that happens, fuel mixtures start to get effected, because the valves are not operating at peak perfomrance.






USERNAME
Use "claim to be" below if you don't want to log in.
PASSWORD
I don't have an account. Sign me up.
CLAIM TO BE
Use only if you don't want to login (post anonymously).
ENTER CAPTCHA CODE
This is required for posting anonymously.
OPTIONS notify by email
Available only to user accounts.
SUBJECT
MODEL/YEAR
MESSAGE

DICTIONARY
LABEL(S) +
IMAGE URL *
[IMAGE LIBRARY (UPLOAD/SELECT)]

* = Field is optional.

+ = Enter space delimited labels for this post. An example entry: 240 muffler


©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.