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



 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

Limp Mode Definition? 700

posted by  someone claiming to be David Johnson on  Tue Mar 18 12:59 CST 2008 [RELATED]

"Limp Home Mode" is a Brick Board colloquium for what happens when the computer does not get a signal from the air mass meter.

The air mass meter uses a pre-heated platinum wire to determine the amount of air that enters the airbox. The resistance and voltage on the wire change in response to the density and temperature of the air coming into the box in order to maintain the wire's temperature. The computer uses the resistance and voltage to figure how much air is coming in and deliver the appropriate amount of fuel.

When the AMM "dies", the computer reverts to a pre-programmed mixture that is very, very rich. The engine will run up to about 2500 rpm, and give you only enough power to do maybe 35 or 40 mph. I suppose the idea is that you can drive the car to a service station or back home. But, if you drive it like this for a long period of time, you risk frying your catalytic converter, and the rich mixture could, in theory, removing the oil coating the cylinder walls.






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.