Date: Tue, 12 Dec 1995 00:01:19 -0500
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: mcleane@nando.net (Ed McLean)
Subject: Re: no start
I also have had problems starting my '86 Vanagon recently. Although this
is a rather long note and Berry Kercheval will recognize it as information
I already sent him, I believe others will also find it interesting and
maybe some might actually find it useful. Let the story begin:
On the first cool day this fall my Vanagon was having starting problems.
Although the starter would turn the engine over at an OK speed, the thing
would not start in the mornings. An inductive timing light indicated that
the ignition system was working. I pulled the wires off of two of the fuel
injectors and hit the starter. I figured if it was flooded, one side of
the engine would clear and I could start it later; and if it was not
flooded, the other side would start. It started. The dealer's mechanic
suggested I make sure the FI grounds were clean and not corroded as the
electrical load of 4 injectors might be too much for a poor ground while 2
injections would be OK. I cleaned them (2 terminals with 5 wires just
under the ignition coil, a ground strap to left cylinder head also from
under the ignition coil, the ground strap at the front of the transmission,
and the battery ground strap) but the problem remained. Since the fuel
injection system is powered through the wire connecting the alternator to
the battery, I checked the voltage available to the fuel injection system
at the alternator while the starter was turning. It was only 6.5 volts
available!! The voltage at the battery posts was only 7.5 volts
(indicating a reasonable 1 volt drop through the body). I attached jumper
cables to the battery and tried to start it again (the other car was not
running at this time) but voltage at the alternator was only about 9.5
volts and it wouldn't start. These are very poor jumper cables! I then
got my wife to start the other car and rev the engine somewhat while I
tried to start the VW. The voltage climbed and when the voltage measured
at the alternator reached 10.75 volts, the engine started and ran smoothly
immediately. Since my battery was near the end of it's 60 month warranty
period, I purchased a new battery the next day (Diehard International Group
41, ~850 CCA. Although I had to trim off some of the hold down tabs on the
end of the battery to get it to fit, it eventually slipped nicely into the
battery box. (Note: A Group 42 battery is smaller and less powerful than
a Group 41 battery. Get the biggest one that will fit CORRECTLY in your
battery box.) Voltage at the alternator is now about 13.2 volts while
cranking. I have had no problems since then with starting.
While this is only one experience with one car, I think it does illustrate
the sensitivity of the electronic fuel injection system to low voltage.
Even though the starter may continue to crank and the ignition system still
spark, the fuel injection system may not have enough voltage to work
properly and the engine won't start. If you are having starting problems,
it might be worth while to check that voltage available to the FI system
WHILE THE STARTER IS TURNING. I don't know what the minimum acceptable
voltage can be but if it is much lower than 10.5 volts you can assume you
have a problem. This probably can be checked just as well at the battery if
the wires and connections are OK and you take into consideration the
voltage drop through the body and long wires. If this indicates there is a
problem, get the battery checked with a load test.
However, there may be a problem with this rational: The new battery may be
providing enough voltage to allow the FI system to operate with a weak
component that will not work at a lower votage. I'll just have to wait to
find out about this but it's working now ...
I apologize for the detail and length of this letter but I thought it might
be information someone could use.
Ed McLean / 1986 Westfalia
mcleane@nando.net
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