Date: Wed, 9 Sep 2009 12:48:44 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: flashing LED
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ok, it's sorted out now, about the coolant temp gauge and the LED.
now on to the oil buzzer issue.
I'm just curious if you are aware that the 2.1 waterboxer engine has a
Dynamic Oil Pressure System ( DOPS ) and that it senses oil pressure at
high and low rpm.
I imagine your oil buzzer is going off at speed - kinda typical for the 2.1
engine with high miles.
the question of course is ......is it really how oil pressure above 2,000
rpm ?
Is it a sensor issue ( the high rpm high pressure switch is the one by the
crnnkshaft pulley )
or is it a DOPS circuit issue ?
Here's a cheater fast test to see if the circuit is working. The high
rpm/high pressure switch uses oppostie logic of a 'normal' oil preussure
switch. It provides ground when things are ok ( opposte of a normal OP
switch ) .
If you disconnect the wire to the switch by the crankshaft pulley, and
ground it, you trick the DOPS circuit into thinking things are fine there.
If the oil buzzer does not go off then, you can conclude that the circuit is
working like it should.
you could also test the OP switch by the crankshaft pulley, by seeing if it
supplies ground above 2,000 rpm.
Rig a 12 volt test light so it is looking for a ground ( not power like you
normally would ) . See if the OP switch supplies that ground at high rpm.
if it does not, either the switch is bad, or the oil pressure is indeed low
at high rpm.
It's also really only a valid test when things are really well warmed up.
You could just put in 50W oil and see if that keeps your oil buzzer off at
high rpm, fully warmed up. That would tend to indicate that your real
problem is oil pressure, and not in the switch or circuit.
There's a whole trouble shooting secton on the DOPS in the Bentley manual
that you could look at.
I don't really believe in oil pumps 'wearing out' or getting weak,
but some people have fixed your problem with a new oil pump. 'Usually' on a
2.1 ...fromn what I read, it's that the stretch connecting rod bolts allow
the rod bearing oil clearance to get too big, eventually. If your miles are
very high , like 200K .........I'd be considering that the bottom end of the
engine might be pretty tired, and that's the real problem.
But you can do this testing to determine if that's what it really is.
You could also put a mechanical oil pressure guage on it, even temporarily,
to find out what the real oil pressure is.
I more or less only use 15W40 engine oil - it that won't work right
..........tired engine I'd have to say.
Scott
www.turbovans.com
----- Original Message -----
From: "Sunshine" <vwbusgirl@KC.RR.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, September 09, 2009 6:35 AM
Subject: Re: flashing LED
>I already got that part down from reading my manuals when I first got
> this vehicle up and running a year or so ago. I do realize what the
> gauge is for and the LED, the COOLANT TEMP and LEVEL. Where I thought
> it might be the oil pressure is when the gauge was reading normal and
> there was NO LED flashing (as of when I drive it's this way) and the
> audible alert beeping was sounding as I would round corners or hit a
> bump, this led others to believe it might be one of the oil pressure
> sensors.
>
> The LED is no longer flashing after bleeding the coolant lines for air
> this morning.
> Have yet to see if the alarm will go off again or not.
>
> THANKS!
> Peace, Love & VW Grease,
> Sunshine
> ~~~~~~~~~~~~~~~~~~~~~~
> '89 Vanagon GL - Wolfsburg Weekender Edition ("Stella Blue") *Daily
> Driver*
> '87 Vanagon GL ("Parts Van")
>
> On Sep 9, 2009, at 8:23 AM, mcneely4@cox.net wrote:
>
>> That little led is not for oil pressure, and that temperature gauge is
>> not oil temperature. Check your manual and you'll find that that
>> gauge is for coolant temperature (sender is on the thermostat
>> housing), and the led responds to both coolant level (in the expansion
>> bottle) and coolant temperature (when overheated).
>>
>> Dave Mc
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