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Date:         Thu, 22 Aug 2002 21:55:29 -0400
Reply-To:     "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
Organization: Bulley-Hewlett
Subject:      Re: Not passing smog, still... Need help!
Comments: To: Steven Dodson <steven@EPOCHDESIGN.COM>
In-Reply-To:  <FCEEIGDOKPNNIFBPGKDJCEAACOAA.steven@epochdesign.com>
Content-Type: text/plain; charset="US-ASCII"

Did you run the MMO as described? If your compression is off you may have a filty ring.

All of this goes back to the bottom line I said before: If your cat is new (as you said) and all the adjustments are correct (timing, etc.) and your air filter, oil, and fuel are clean, and if you have REPLACED YOUR OLD O2 SENSOR, there is no reason for you not to pass smog unless your motor is completely toasted, *(which your compression numbers do not bear out.

Run the MMO. Replace the O2 sensor. GO PASS SMOG, and move on to more interesting pursuits, like adding scoops to the sides of your van.

Developing business and guiding change since 1996,

G. Matthew Bulley Bulley-Hewlett Marketing & Communications Business: www.bulley-hewlett.com AIM = IExplain4u Phone: +1.919.658.1278

-----Original Message----- From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf Of Steven Dodson Sent: Thursday, August 22, 2002 9:17 PM To: vanagon@GERRY.VANAGON.COM Subject: Re: Not passing smog, still... Need help!

Danke, Her Keller!

The compression test today showed might fine compression in all but #4. #1=130, #2=128, #3=132 and #4=98-100 (hard to call). With a few shots of oil into the cylinder, #4 blossomed to a whopping 132, must be a ring problem. Is the ~100psi good enough for now? I'm not trying to be cheap here, but as I've mentioned before, I plan to do a Diesel conversion and don't want to dump a bunch of money into this WBX.

I will do this spring tension adjustment as well as a CO and idle adjustment per Lord Bentley. A List member said to adjust CO to .5V, when Bentley says .7V. Thoughts? Any input on which to perform first?

I think I need to blow out the injectors again, since I changed the fuel filter. Syncro fuel filters are in the worst (dirt catching) place. I should do this before doing anything above. Ja?

-Steven Dodson Kneeland, CA "Inga" the 87 Syncro

-----Original Message----- From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf Of Mark Keller Sent: Thursday, August 22, 2002 4:49 PM To: vanagon@GERRY.VANAGON.COM Subject: Re: Not passing smog, still... Need help!

Steve,

It seems more to be your basic engine fuel injection is just out of adjustment. I call this depending on the O2 sensor. I'm just taking a midday break, and you may have solved this by now, but I wrote recently on how to set up the spring tension on the AFM.

The other issue that hadn't been addressed as of my following the thread, is that an oil change is helpful, as fuel can be present there.

If your still not below the idle HC, then read my posts on adjusting the basic fuel injection with a digital voltmeter and the O2 Sensor disconnected and your van should be a go. I've added it below as it was orginally for another topic

Sincerely,

Mark Keller

Adam,

Probably a mis- adjusted fuel injection system. My 91' behaved this way

too. In fact my wife wouldn't drive it because of the "lag" from when you hit the throttle to when something actually happened.

Any way I solved it by doing the air flap AFM adjustment that deals with

spring tension. I wrote about last year, archives should have it

For the best result consider, double checking the timing, and vacuum hose connections, some vans screw up the pressure regulator and distributor hose connection and they come from different sources. Also cleaning the wiper arm on the AFM , beneath the black cover. The cover is off for this whole procedure.

Check again the following that the idle and WOT switch is functioning unplug at the connector and with the engine off , just read the ohms as you operate the throttle. Should be continuity at full closed and full open. I think a .005 th feeler gauge at the idle stop screw is the tolerance, i.e. it should stay continuity until the throttle is open that far. The adjustment is the two allen screws below the throttle body housing. ONe locks the adjusting mech in place, loose it, the other makes the adjustment.

If you want to skip all of this cause you have tinkered with it in the past proceed, otherwise consider doing it. Also if you email me, I'm on

digest, I work with you to getting your van nice and snappy off the line.

In case the archives don't suit you at the moment here is the main idea is:

Go open loop , i.e. disconnect the O2, connect a digital Voltmeter to the O2 black lead on a long wire, I used microphone cable, so that you can view the mixture in volts while driving. The test target is to have

.5 volts or so at 3000 Rpm plus while driving, steady cruise, level-ish

ground etc. yes is will move around some but it will stay relatively stable enough for you to determining whether the system is general lean,

.4 volts or less or rich .6 volts or higher. The values for the O2 Seem

to be .3 and .7 volts. The best lean of .15 and best power of .86 are targets taken form Probst Book on Bosch Fuel injection., keep your level cruise target to .5 or .6 volts. The injection system has a curve built into it for acceleration and deceleration and the vacuum to the pressure regulator is what keeps it all happy.

Adjustment is by changing the spring tension on the AFM flap. No need to remove the wire gizmo that locks the gear in place, just lift up the wire, move the gear, I THINK it was CCW 10 teeth for mine, put reference

scratch on you starting position.

This takes a tweaking or spiral engineering, to close in on a good setting. BTW, I was extremely pleased with how well the open loop fuel injection system control the mixture, in fact the Van runs better, but the O2 is needed to protect the Cat for getting an over rich mixture and

melting should something go wrong during normal operation. YOu might as

well locate a hill, and then go up at 4400 RPM and see if the fuel pump / pressure regulator keep you mixture at above .5 volt during the climb. This test the system for a possible lean out, when you really need a power mixture, A. cooling, B. Power. Anything below the .3 mixture is unacceptable. If the spring tension is giving good mixture at all other driving condition with the EXCEPTION of a full power WOT hill climb of at least a minute or so, then I would look at the fuel deliver system, pump and or regulator. Keep in mind this is done without the O2 sensor connected to anything but the Volt meter.

Anyway, Having done that, go back home and set your basic idle at 840 Rpm, idle motor disconnected at it's plug. Use the large flat head screw on the throttle body, putting a dot on the screw and the body for reference before beginning helps keep your orientation.

Idle air bypass adjustment- Next remove the 10 mm or plug on the top of the AFM, mine had been done before so there was already a 7/64 ths dia..

hole there to screw a #8 sheet metal screw into. Do that, wiggle the thing out. Get a 6 mm allen wrench, put some 3M body caulk around the wrench, as an air gasket, I just leave my in instead of replacing the plug. Ok all of that was so you could look at the voltmeter and adjust the Idle air bypass screw. Again look for .5 volt, yes it will float around, but it should hang between .3 and .7 volts

Of course once the IDLE Air by pass is set, the idle will be off some, re adjust the idle screw, now the idle bypass screw, until they both are

at the target setting.

Go back out and drive the van and your throttle response should be amazing!!!

Sincerely,

Mark Keller

91 Carat


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