Date: Thu, 18 Jan 2007 15:07:29 -0500
Reply-To: Geza Polony <gezapolony@SBCGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Geza Polony <gezapolony@SBCGLOBAL.NET>
Subject: Re: Moral qestion--Now diagnostics
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
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