Date:         Fri, 6 Jun 2014 10:36:48 -0500
Reply-To:     JRodgers <jrodgers113@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         JRodgers <jrodgers113@GMAIL.COM>
Subject:      Engine turns - Fails to start - Trouble Shooting
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I have been having a conversation about this with fellow Vanagoneer Jeff
Palmer and decided to write this up.

His question was: "Are your current problems similar to the ones on your
vans a couple of months ago on the one you sold"

Here is my response. I hope it helps someone.

John

 >>
Jeff,

Both were hard starting. But when I did the test - one indicated a bad
coil. I replaced it and no more problems. On the other the test showed a
bad Hall sender. Because of the mileage on that vehicle - over 200,000 -
I opted to just install a rebuilt Bosch distributor that came with the
new Hall sender.

The current problem acts similar. Engine turns rapidly - but will not
even fire. Definitely have fuel to the injectors, definitely have air -
but no fire. But that could be the coil, the hall sender or the ECU. The
Hall sender  sends a timing signal to the ECU that tells the ECU when to
pulse the injectors and when to pulse the coil. If the EU does not get
the Hall sender signal - it will not fire. But if the coil is bad - it
also will not fire. So the test differentiates between the two.

Three steps:

Pull the distributor wire, crank the engine, hold the distributor wire
1/8 in from the engine block or other ground point - you should get a
spark. If not - go to the next step.

Pull the Hall sender plug from the connection behind the distributor.
There are three terminals inside the plug. The two outside terminals are
power and ground - the middle terminal is the connection to the ECU and
provides the signal to it. Stick a small pieces of wire into one
outboard terminal = clip a test light to it, and with ignition on -
touch the test light probe to the other outside terminal. If it lights
up - then power to the Hall sender is good and the ground is good.

Go to the next step.

Put the wire in the center terminal and touch it to a clean engine
ground point.  You should get a spark from the coil wire every time you
touch that center lead to ground. Also - the injectors will pulse and
you can hear that.

Synopsis:

Spark - Yes:  Ignition control(ECU)  is good, coil is good. Replace Hall
Sender.

Spark - No: Check the coil and the ECU. Most likely failure is the coil.

Having a spare coil might not be a bad idea. It's probably the easiest
way to check the ECU for proper operation. Just R&R the coil and see if
it runs.

Given that my problem is intermittent - I just have to wait until it
happens - then quickly do the tests. If there is an "Open" in the
circuit - it will show up then.

This test is easy and quick.

Good hunting,