Hi.

My cruise is dropping speed after approx 5 minutes- slowly it`s retarding speed. Any tips for this?
81`model car.


Br
Jørgen

 

Check vacuüm for leaks

 

Do a search on cruise control problems. That is one of the major problems with early cars. It could be anything from a vacuum leak to a cold solder joint. Good luck .

 

Seems more likely to be vacuum related if it takes 5 minutes to manifest.

There's an extensive diagnostic testing section in the workshop manuals.

 

Vacuum leak testing to be performed.
Thanks!

 

you might try blocking the feed port for the HVAC system ( black feed line)
then testing the CC.
NOTE could be dopne at the brake booster location.

If the HVAC system is leaking then its probably the fresh air pot in the blower box and the 2 others in the center of the console,
the defrost pot doesnt usually leak as its rarely used (this one is over the ignition switch).

If the test doesnt change the condition of the CC then try resoldering the connector pins on the board and the tall tower looking thingy on the corner of the CC board