Date: Wed, 30 Mar 2016 12:28:52 -1000
Reply-To: "SDF ( aka ;jim lahey' - Scott )" <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "SDF ( aka ;jim lahey' - Scott )" <scottdaniel@TURBOVANS.COM>
Subject: Re: Engine Cranks but No Start
In-Reply-To: <vanagon%2016033013470513@GERRY.VANAGON.COM>
Content-Type: text/plain; charset=windows-1252; format=flowed
super easy to test for,
takes literally seconds.
pop your NOID light on an injector wire, crank the engine from back
there with a Remote Starter Switch ..if light flashes, injectors are
being fired by the ecu.
fwiw...... I have not ever seen on a stock vanagon where starter cranked
fine but ecu couldn't wake up. Possible for sure, but in hundreds of
vanagons I've never seen that one.
here is a simple 'must have makes things super easy' Testing Tool List -
Remote Starter Switch
NOID light for injector signal.
12 volt test light
digital volt-/ohm meter
jumper wire or two
< lol..the fuel pump can be jumpered at the fuel pump relay with even
a little screw driver..just by opening that relay box cover ..you don't
even need the ignition key for the van to do this ! >
IR Temp gun ..very important !
( I just tracked down intake leaks on one side using one of these,
reading exhaust pipe temps ..took all of 30 seconds )
fuel pressure guage
timing light
spark plug wire insulated pliers
compression gauge
rarely ..a vacuum gauge
also rarely .....a little inductive 'spark plug wire flashing
pen-shaped' tool.... is handy sometimes...shows if that plug is firing
. ( that's what I mainly use an inductive timing light for ..to see if
all plugs are firing steadily, and sometimes for actual timing of course )
since we are talking starters ...
there's a simple tool called an inductive amp gauge ..there are more
evolved ones of course..
but mine is a small square gauge you just hold over a main battery cable
while cranking the starter ..it reads out in Amps. You see an extra
high .say 200+ amps reading, during starter cranking ..
you start thinking about that whole circuit and the starter itself.
notice Remote Starter Switch is at the top of the list.
That's my first tool to grab on any starter cranking issue.
also ...due to compression, engines stop in the same 4 places on the
starter teeth.
So some teeth get more wear than others.
I've also had a fair amount of bad Bendix Drive Gears ..
symptoms are ...it kicks out before you are ready for the starter to
stop cranking..
or ..it intermittently won't crank the engine steadily.
last time I needed one for a 50 year old Mercedes car, I took the Bosch
number off the side of the starter to an electrical rebuilder shop. The
part was like $ 25.
Tricky to change on the starter, but that fixed it fo' sure.
Scott
On 3/30/2016 7:47 AM, Ed McLean wrote:
> If the voltage, measured AT THE BATTERY with a digital volt meter, is less
> than 10.4 volts with the starter turning the engine the ECU will not work
> correctly and it won't start. The starter will, however, still spin the
> engine over pretty good at this voltage. I've forgotten if the ECU will
> fail to produce spark or fail to activate injectors at this voltage
> because it was about 18+ years ago this happened to me.
>
> A simple way to check is to try a booster battery to make sure there is
> enough voltage. If it starts, you probably need a new battery although it
> could be something wrong with your charging system.
>
> I've been thinking that maybe the tachometer will not work if the ECU is
> below this voltage threshold. Check to see if the tach needle indicates
> the appropriate cranking speed while cranking. If it is correct, you
> don't have any new information but if it doesn't indicate correctly you
> know that the ECU isn't working. I don't remember what the tach did when
> my '86 had this problem.
>
