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Date:         Sat, 9 Dec 2000 22:52:20 -0500
Reply-To:     "Dave C." <vinniethe85vanagon@MAC.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         "Dave C." <vinniethe85vanagon@MAC.COM>
Subject:      Re: 85 with uneven idle/poor fuel economy (response long and
              thorough)
Comments: To: Dugbare@AOL.COM
In-Reply-To:  <7c.e98abbc.2762e409@aol.com>
Content-type: text/plain; charset="ISO-8859-1"

on 12/8/2000 8:25 PM, Douglas Miller at Dugbare@AOL.COM wrote:

> > > From: Dugbare@aol.com > Date: Friday, December 8, 2000 7:22 PM > To: jromas@COLUMBUS.RR.COM, midwesty@MIDWEST.NET, kdlewis@JUNO.COM, > Dhaynes57@EMAIL.COM, CTONLINE@WEBTV.NET, poll7356@UIDAHO.EDU > Subject: 85 with uneven idle/poor fuel economy > > Gentlemen, > I've found you through the archives, and also followed the threads you've > posted in the last 2 months relating to my problems. > I've just started experiencing this problem, and at the most unopportune > time due to leaving next Saturday(16th) on a trip from Northeast Pennsylvania > to Northwest Montana. Approximately 2500 miles, and artic air forecasted > across the plains next week. > My routine maintenance within the last 10,000 miles has been: new > plugs,plug wires, rotor/cap, oxygen sensor, fuel/air filters, new > muffler/tail pipe & cat, oil change, fuel pressure regulator. > My situation on my 1.9l is this: my van is running very strong but the > fuel economy has dropped to 13-14mpg. Now the diagnosis: When cold, the van > starts and idles fine with no lagging or problems as it accelerates. Within > about 5 minutes when it warms up, it goes through the "stumbling idle" > sydrome as Mick Kalber stated betwen 1000-1800 rpms. As I've cleaned the AFM > a few times with electronic cleaner and cotton swabs, I noticed definate wear > marks in each of the tracks. When idling, the arm is riding right above the > wear marks. I've adjusted the arm so very slightly and it has improved the > "stumbling" to 1100-1400 rpm. I could live with this but my fuel economy > hasn't improved. > So I finally went out and bought a digital multi-meter at sears the other > day and spent this afternoon learning how to use it and Bentleys diagnostic > charts on 24.20 & 24.21. These are my findings: Temp I & Temp II sensor were > within range at air temp(TempII/27 degress F-6820 ohms, I'll check Sears to > see if the model I bought has a temp probe), Oxygen sensor was fine, air > intake was right on, and now to what I belive is my culprit, the AFM. It > reads 1200-1400 ohms until I get within 1/4" of the "wear spots". Then it > starts shooting skyward until it tops out at 13,000+ ohms right above the > wear marks. Then decreases back to the 1200-1400 ohms as it travels to the > end of the tracks. > My questions are: can I adjust the arm just so ever slightly so that the > fuel economy is there, or does it sound like the AFM is shot. > Any and all advice from you all would be deeply appreciated, especially > on my wallet/fuel budget for my trip. > Thank you so very much for the help and info. > Doug Miller 85 GL The Blue Whale > 73 Thing >

Bully's not around much these days so I guess I'll do one. ;> Not to say that I lurk mostly now and it's about time I said something. A shout out to KenW&Chris? in SLC and my buddies in PA/NJ!

This is everything I can think of (setting aside presence of vacuum leaks) that can and will affect the idle quality of the venerable 1.9L Wasserleaker. The list is in order the way I would progress through them if I were there with you and the van. I've done everything here over the past 3 years and Vinnie, our 85GL Westy, has been dead on for quite some time now. If you are in this van for the long haul then I'd prolly replace most of the remaining sensors and keep the old ones along as b/u on a remote or long trip. But that's me. I look to have Vinnie for as long as I'm allowed.

Precautionary note: Be aware of suggested electrical protocol for connection activity and energizing. One can fry expensive stuff.

Replace Temp II sensor. They can 'test' and look right and be wrong. Just get another one as they are cheap compared to the aggravation they can cause. Test idle control unit on the firewall. Replace if necessary or just do it anyway. Clean coil contact wires and mounting terminals. Inspect for wire breaks. Clean distributor contact wires and mounting terminals. Inspect for wire breaks. Clean firewall contact of flat braided ground wire from left cylinder head. Clean all of the vehicles ground points, ground wires, and sensor contacts really well. Start front and work to the back where most of them are. Brighten up the mounting bosses and electrical contacts on the alternator and adjust belt if necessary. Check O2 sensor wiring. Regarding the green wire that runs into the wiring harness: this is coaxial wire and has a braided sheath. If this has been spliced, verify that no short is present between the connector and the sheath. Clean and verify throttle switches correct adjustment on throttle body. Check throttle body intake boot for cracks or other problems. Clean electrical contacts on starter and fuel pump just for good measure. Run a bottle of TechronŽ through one tank of gas. Does wonders for the injectors. Continue once between every oil change. Given the reported condition of your swiper board, replace AFM. I replaced mine with a new one at 200k miles and figured that was an acceptable life span for a part that moves as much as it does. Install extra ground wires in the AFM body itself [there's a 13mm tapped hole on the leading (front) side] and to the passenger side head. That grounds the engine three times as opposed to just one and helps to eliminate static charges theorized to build up within the polysomething-or-other air filter body. Someone even reported great success with fashioning a multi-stranded "charge filter" from regular wire installed via a small hole in the filter housing itself. Never did that one myself though. Its on the list of things to do, just not very high priority. Anything to prevent digital FI calamity! Get the van set up at a shop with a CO meter, timing set right, idle set right and an enlightened tech tweaking it all. I'll suggest that as you travel, plan a route through Allentown, PA, set up a visit at Bernhard's (bernhards.com) and let Ed's fellow (Paul I think his name is) get it all tweaked.

It should be dead on then and for a long time.

If all that doesn't fix it­it's the brain. A shop would throw a brain at it first to the tun of $6-700 dollars and tell you that there's nothing else to check because it's all solid state.

Cheers, Dave C. Williamsburg, VA zzzzzzzzz__ |E[__] [__]|[_]\\ | _DC&SP | _ || * * * =-( )---------( )--= '85 GL Westy (His) '91 Cabriolet (Hers)


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