

| Subject: | Re: strange idling behavior ? (long post with plenty of diagnostic hints) |
| From: | neil N |
| Date: | Fri, 14 Nov 2008 18:43:53 -0800 |
Don. I'd check for a vacuum leak first. I don't know Digifant, but vacuum leak is my first thought. Also check out the Vortex.com They should have a section dedicated to your fine 1.8 8V. Not mentioning that it's in a Vanagon may help, though the guys on the 2.0 list have been most helpful and some were even interested in my conversion. Cheers, Neil. On Fri, Nov 14, 2008 at 6:17 PM, Don Hanson <dhanson@gorge.net> wrote: > 84 vanagon with an inline VW 1.8 motor. > > Not really a vanagon question, I guess but many on the list seem pretty > familiar with the little inline 4 VW motors. They also have the same or > similar fuel injection to vanagons, so Helpful hints would certainly be > appreciated as to where I might look. > > This little 1.8liter, 8-valve, from a '92 rabbit cabriolet (Digifant II > injection) , has always behaved perfectly until just this morning. Upon > start up..not super cold or anything, the idle didn't drop like it always > has after the motor warmed up. It usually runs at like 1200rpm for a few > minutes, then drops down to a normal idle..This morning it seemed to be > idling a little higher than normal, and it didn't fire up and settle right > into it's pace, but kinda stumbled around a bit, then settled in at it's > warm up RPM. (no throttle from the gas pedal, ever) > > No dash warning lights, no abnormal driving preceded the onset of the > problem, all the gauges read the same as always. I did run the tank dry a > few weeks ago and I have noticed my fuel pump is slightly more audible than > before, but I've had no indications that the fuel pump is having > problems...yet. And it does run fine down the road.. > > I headed out, with the high idle, and at my first normal stop sign, the > idle was still up at around 12-1500rpms. It normally would have gone to > it's regular idle (about 7-800rpms, I guess) mode by that point, but not > today. Then, as I came into the next stop-after about 20 miles of highway > speeds,( totally normal behavior, other than the high idle between shifts)- > the idle was "hunting"...it was doing about 3-second cycles...Up to > 1500......down to normal....up......down... up..I blipped the gas pedal > without any effect to the hunting...It did that for my cross town trip of > about 3 miles and a couple of stop signs, then I shut it off and went bike > riding...It cooled down for about 2 hours then. > Under throttle, when driving, everything seems to be running properly. No > smoke, no missing, no detectable loss of performance. Weird... I drove > around town and put about 45 miles on today with no problems other than the > high/and or/hunting idle.. > Just now, coming home, the 'hunting' has stopped again, but the idle > remains much too high...1500+ rpms (guess-ti-mate) I left the van running > and went round to check the exhaust...smells normal..not super-rich or in > any way stinky. > > So, any guesses or suggestions? First thing I'll be looking at will be > the Temp II sensor, my guess. That seems to cause all kinds of weirdness in > the Digifant II system and other VW injected vehicles. I have never been > able to find a 'throttle position switch' on this vehicle...but then the > Bentley I have (for the Cabriolet motor) is not worth squat on that > particular point..I may not have one, who knows..I wouldn't think that would > cause the "hunting"...Hope it isn't the EMS Brain... > > Thanks in advance...Hey, it's even Friday so if this isn't list > appropriate..it's at least posted properly.. ------------------------------------------------------------ + To unsubscribe from the Vanagon List send an e-mail to + listserv@gerry.vanagon.com with SIGNOFF VANAGON + in the body of the message. ------------------------------------------------------------
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