Dan, The cold idle circuit of most Bosch fuel injection systems incorporate an "auxillary air regulator". When you start the engine, this valve is open, allowing additional air (and hence gas) to be consumed by the engine. It is electrically operated... a 12V lead attaches to the top. As the engine gets warmer, the 12 volts acts on the internal valve of the auxillary air regulator, causing it to close its valve. The internals of this regulator get gunked up over time, and the mechanism to close the valve gets tired. A way to test if this regulator is doing its thing is to start the engine, then pinch the hose coming from the regulator to the air intake housing. There should be a decrease in rpms. After running the engine for 5 minutes or so, pinching the regulator should cause no effect on rpms. I've tried to repair these regulators, but usually the innards are so tired, they die again quickly afterward. So a new replacement is usually called for. Paul Henderson '84 Vanagon WasserBoxer Bedminster, NJ, USA |
Please note - During the past 17 years of operation, several gigabytes of
Vanagon mail messages have been archived. Searching the entire collection
will take up to five minutes to complete. Please be patient!
Return to the archives @ gerry.vanagon.com
The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.
Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.