M-kay, then what I might want to do is tune the engine w/ the O2 sensor disconnected, yes/no? For you guys that work on 1.9L Digijet engines -- what are the "knobs" I use for the tuning? Timing is one, what else we got? Or, to put this another way: what might I tell the shop to do w/r/t this? Hey shop: 1. Disconnect O2 sensor . . . then 2. What? -- Mike "Rocket J Squirrel" Elliott 71 Type 2: the Wonderbus 84 Westfalia: Mellow Yellow ("The Electrical Banana") 74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano KG6RCR
On 8/3/2008 5:17 PM David Beierl wrote: > At 07:32 PM 8/3/2008 -0400, Allan Streib wrote: >> Wait a minute -- so you are saying that in theory if a US spec Vanagon >> has had the cat removed and is running a straight pipe that it does >> not need an O2 sensor at all? > > Not theory. O2 sensor is strictly emissions-related and enforces a > very narrow range of mixture oscillating back and forth across > stoich, which is what the three-way (nitrogen oxides, carbon > monoxide, hydrocarbons --> nitrogen, CO2, water) CAT requires. It > prevents tuning the motor for either max economy (leaner) or max > power (richer). > > As a *side-effect* it will compensate for other difficulties that > affect the mixture equally across all four cylinders -- thus making > them impossible to diagnose without disconnecting the sensor. As a > different side effect, if one cylinder is misfiring or there's an > exhaust leak upstream of the sensor it will drive the mixture way > rich trying to get rid of the excess oxygen. > > > -- > David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/ > '84 Westy "Dutiful Passage," '85 GL "Poor Relation" > |
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Vanagon mail messages have been archived.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.