Given all that, I really like what Dennis H. says:

"do a leak-down test". At this point, that seems to make the most sense.

J

On Thu, 18 Jan 2007, Geza Polony wrote:

> I cleaned the battery terminals with acid and brush. Transmission was
> replaced a year ago but I'll get out there and clean that too. Other grounds
>  in the engine compartment I cleaned and replaced with an entirely new
> ground web that covers everything from the 02 sensor to the cylinder heads
> to the frame to the ECU. So grounds there are actually doubled.
>
> I've removed and replaced the idle stab, including running without on, with
> no effect.
>
> I've done the Bentley FI test sequence at the ECU connector and everything
> checks out fine. Maybe I should do it again, though.
>
> >From the files you attached, it sounds like exactly the same sort of
> problem. And the same sort of frustration. BTW, I've changed out the Temp 2
> sensor several times-no change.
>
> One thing I'm starting to think is this. Each component of the FI system, at
> 20+ years old, is SLIGHTLY off its original specs, to say nothing of the
> compression numbers and the fuel injectors themselves. Each electrical
> component may check out within specs using a VOM, but the combined error
> would be enough to throw off an otherwise good idle. Let's say the Temp 2
> sensor (new) is off 1%, the ECU is tweaked another 1% in terms of the pulses
> it sends to the injectors, the 02 sensor is not quite as responsive as it
> should be, and there's carbon buildup on the heads. The combination of ALL
> these minor errors could lead to the kind of problems I'm talking about.
>
> No? And how are you going to correct them all without buying a new engine
> and all new components?
>
> God forbid paying a mechanic to figure that out!
>
>
>
>
> On Thu, 18 Jan 2007 14:47:34 -0500, Sam Walters <sam.cooks@VERIZON.NET> wrote:
>
> >Geza,
> >
> >
> >You said you checked the grounds, but didn't say you cleaned them all.
> >There have been many instances of stumbling FI type problems being cured
> >when the owner cleaned the grounds, particularly the ones on the
> >negative terminal of the battery and the transmission.  Of course, all
> >of them are important.  But people several people who thought their
> >grounds looked good have solved a difficult problem by cleaning a ground.
> >
> >As Jon suggested, the idle control unit can be the problem - it plagued
> >my 84 for a couple of years and no one could find it although they took
> >lots of my $$ while searching and installing unnecessary parts.  After I
> >found the list, I figured it out and got one from a list vendor for $30
> >and installed it in 5 minutes.
> >
> >Disconnect it and connect the ends of the plugs of the wiring harness
> >that came out of the Idle Stabilizer/Control unit.  You can drive a long
> >time this way.  It may make for rougher running in cold weather.  If the
> >problem disappears, and reappears when you reconnect the unit, it is an
> >easy fix.
> >
> >It isn't that hard to take the voltmeter and the Bentley and test
> >virtually every component in the FI system.  This will help with regard
> >to things like the injectors as mentioned by Jon.  There is a set of
> >tables that tell you how to test many components through the holes on
> >the wiring harness ECU connection and pages of material for checking
> >individual components.  It is a bit daunting the first time you do it,
> >but it can easily identify a problem.  I have been learning to do this
> >lately on my 85 Weekender with the Digijet controlled 1.9l engine.
> >
> >Look at the attached files for some suggestions for diagnosis.
> >
> >Good luck,
> >
> >Sam
> >
> >--
> >Sam Walters
> >
> >Baltimore, MD
> >
> >
> >
> >Some of you might have read my posts about thinking I had timing problems
> on my new 1.9 in my '85 Vanagon.
> >
> >Upon furthur sleuthing, cyl 1 and 3 seem to not get any gas.
> >
> >If I pull the connectors going to either 1 or 3 when the motor is running,
> it keeps on going, If I do that to either 1 or 4, it dies !
> >
> >I've troubleshot as per the Digijet F.I. manual, metering on the ECU
> multi-pin connector, and all my injectors measure out to 18 ohms as per spec.
> >
> >However, what is REALLY odd is that the book states the following for the
> >respective terminals to the ECU:
> >
> >11 & 7 to cyl 2   Mine meters to cyl 4
> >12 & 7 to cyl 1   Mine meters to cyl 3
> >23 & 7 to cyl 4   Mine meters to cyl 1
> >24 & 7 to cyl 2   Mine meters to cyl 2
> >
> >And what is odd is that you cannot mistake the injector wires and their
> bundle to cyl 1 & 2 because they are longer and have to go ACROSS the
> engine. The respective wires to cyl 3 & 4 are only like 8" or so from the
> main cable bundle to the ecu !!
> >
> >I am getting spark to ALL 4 cyl.
> >
> >If I disconnect either plug 2 or 4 when the motor is running (Yes, your 1.9
> WILL run on 1 cyl !) you can definatly smell the unburned gas in the exhaust
> and on the plug.
> >
> >If I do the same for plugs 1 and 3, nothing, no gas smell, nothing.
> >
> >Also plugs 1 and 3 are clean, out of the box clean, 2 & 4 are showing use.
> >
> >What's up ???
> >
> >Frustrated in Memphis !!!!
> >
> >Ken Wilford replies:
> >
> >Is this the first time you are trying to run your new engine?  I would check
> >compression on these two cylinders that you are having the problem with.  My
> >guess is that they will have zero compression.  The reason for this is that the
> >push rods that are not properly seated in the lifters.  This is very easy to
> >mistakenly do (I know about this problem and still do this from time to time).
> >If the push rods are not properly centered in the lifter then they will hang
> >the valves open and cause zero compression.  The solution is to remove the
> >rocker arm assembly on the side that you are fixing and reinstall the push rods
> >being sure to center them.  Reinstall the rocker arm assembly.  Then adjust the
> >valves to zero lash (just touching the ends of the valves).
> >
> >It is probably not a fuel injection harness problem (just my experience again).
> >FYI the injectors are not individually pulsed.  They are all pulsed at the same
> >time and that is why you can plug the wiring harness into any injector (if the
> >wires will reach) and it will not make a difference.  You can test the actual
> >wiring by swapping the wiring on one side from one injector to the other.  If
> >the non-fire follows the injector plug then you have a wiring problem, if it
> >doesn't then you have a different problem.
> >
> >The only other thing that I can think of if you do have good compression is
> >that you have two bad injectors.  This is possible, but most of the time these
> >fail by leaking, not by not opening (just my experience).  Hope this helps you.
> >
> >Thanks,
> >Ken Wilford
> >www.vanagain.com
> >John 3:16
> >
> >--
> >Thanks,
> >Ken Wilford
> >John 3:16
> >http://www.vanagain.com
> >Phone: 856-327-4936
> >Fax: 856-327-2242
> >
> >85 Troubleshooting
> >
> >From:         John Clavin <jc@AUSTIN.RR.COM>
> >Subject:      Engine Cutout
> >In-Reply-To:  <200201022050.g02KoCll011338@txmx01.mgw.rr.com>
> >Content-Type: text/plain; charset="us-ascii"; format=flowed
> >
> >After continuing to work the usual cures for my persistent problems with
> engine stumbling or hesitation, the problem has only gotten worse with my
> 1985 Vanagon during the past two months. The latest episodes, which now
> occur daily, involve the engine completely cutting out. The tach crashes
> *hard* to zero and the engine is *dead*, only to mysteriously revive a good
> one or two seconds later. Here is the status of my anti-stumbling efforts to
> date:
> >
> >AFM - reconditioned unit just installed (did wonders for overall
> driveability, eliminated surging, and smoothed out the idle - but no effect
> on the cutout problem)
> >
> >Throttle Plate Switch - installed new cam, adjusted correctly, switch tested ok
> >
> >Temp Sensors - resistance measures within limits per Bentley
> >
> >From:         Laurence Smith <lsmith@COGECO.CA>
> >Subject:      Re: Power loss still in '85
> >Comments: To: Andree Hurley <ahurley@VIEWIT.COM>
> >In-Reply-To:  <Pine.BSF.4.30.0201121148390.56320-100000@bemnet.pair.com>
> >Content-Type: text/plain; charset="us-ascii"
> >
> >I think the fuel injection is suspect. It can be a PITA to diagnose and
> resolve.
> >
> >Based on the numerous fuel injection problems posted on this list and your
> description of the problem I would break down the cause into probabilties:
> >
> >The high probabilty stuff first: * Worn out Air Flow Meter * Temp II sender
> gone bad
> >
> >Medium probability: * Timing * Idle stabilizer * Vaccuum leak * O2 sensor
> >
> >Low probability stuff: * ECU * Fuel pump * Fuel pressure regulator *
> Throttle switch * Collapsed catalytic * Ground wires * Hall sender * Gummed
> up injector(s)
> >
> >Most of this stuff can be tested with a voltage/ohmn meter and a Bentley
> manual.
> >
> >My guess: Temp II sender
> >
> >Laurence Smith Hamilton, ON 90 Westy (fanumbos)
> >
> >From:         Chuck Mathis <CMathis227@AOL.COM>
> >Subject:      Re: 1.9L bogging down on acceleration when hot..anyone ideas???
> >Content-Type: text/plain; charset="US-ASCII"
> >
> >I went through a whole bunch of stuff to try to eliminate a similar problem
> with my '85. Start with the cheap stuff first.
> >
> >Make sure the intake boot is well attached and in good condition. (This was
> actually my final solution after all the other stuff.) Check the carbon
> track in the AFM -- mine had a bad spot just above the normal idle position.
> I enlarged the screw holes in the board and shifted it so that the arm ran
> on a fresh track. (This was my next to the last step and solved most of the
> problem.) Check on the condition of all the vacuum lines -- especially those
> small ones attached to the fuel pressure regulator. Check the fuel pressure
> and function of the fuel pressure regulator. Try tightening the AFM spring
> some. Be sure to keep track of the number of notches you move the wheel --
> you may want to put it back at some point.
> >
> >Chuck '85 Wolfsburg Westy - 'Roland the Road Buffalo'
> >
> >Idle Stabilizer - new, but bypassing it seems not to make any difference
> with respect to the cutout and stumbling problem (in fact, with the new AFM,
> the van runs just as good without this thing, so I have left it bypassed)
> >
> >Ignition Coil - resistance checks ok per Bentley (are there other tests?)
> >
> >Hall Control Unit and Sender - pass all voltage and operating tests per Bentley
> >
> >Cap & Rotor - good condition, relatively new, rotor ohms out ok
> >
> >Plug wires - good condition, resistance ok per Bentley
> >
> >Plugs - W7DTC, relatively new - replacing them did not help.
> >
> >O2 sensor - relatively new, replacing it did not help.
> >
> >CO screw setting - 1-3/4 turns from bottom (remanufactured AFM came set
> this way). Checked setting against O2 sensor readings and concluded after
> some adjusting that this was a good setting - O2 sensor readings oscillate,
> crossing over 0.5 volts, during "normal" warm idle.
> >
> >Idle setting - who knows? Most of the time it idles 900-1100. but then some
> times it revs back and forth from 1000-1500+, other times it stays at 1500+
> and only slowly comes down. I don't know how to set the idle adjust screw
> under these conditions.
> >
> >Timing - running approx 3-5 deg ATDC (spec for '85 is 5 deg ATDC) - have
> experimented with settings from 5 deg BTDC to 5 deg ATDC, some differences
> in driveability but no setting seems to eliminate the cutout or stumbling.
> >
> >Grounds - all grounds coming off the left side of the engine ohm out ok
> >
> >ECU - visually inspected the circuit board - all solder joints look good,
> no signs of any overheating
> >
> >Vacuum lines - all in good condition, all vacuum devices tested for leaks
> and checked out ok
> >
> >Fuel pressure regulator - measured a few pounds higher than Bentley calls
> for (both with and without vacuum)
> >
> >Fuel filter - will change it this week (but gut feel and past experience
> tells me this is not going to make a difference)
> >
> >After doing some lengthy searches on the archives (again!), it appears
> there are lots of reasons for stumbling, but some people who have had the
> severe engine cutout as I described ultimately traced it to a bad ECU or
> Hall Sender. Is this true? Anyone have a different experience? Anyway, I am
> concentrating my next efforts on these plus the cabling and &$#*& plug on
> the distributor that connects the Hall Sender. Other opinions, suggestions,
> and guesses are eagerly solicited. I am getting desperate -- at this point I
> am even willing to replace the front bumper if there is the slightest chance
> it could help. However, funds and patience are becoming exhausted.
> >
> >Are there any other tests (besides Bentley) to perform on the Hall Sender?
> Can this thing become intermittent and still test good per Bentley? Any
> ideas regarding the likelihood of it being the Hall Sender vs. the ECU? Is
> there a kind soul out there in the Central Texas area with a known, good ECU
> spare I could borrow for substitution testing with mine?
> >
> >I don't deserve this... really. I still have the original German air in my
> Continental spare! I need my life and my van back. Help...
> >
> >John Clavin 1985 Vanagon GL Austin, TX
>