Date: Sun, 9 May 2010 15:43:40 -0400
Reply-To: B Feddish <bfeddish@NETREACH.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: B Feddish <bfeddish@NETREACH.NET>
Subject: Re: Help with stalling van
In-Reply-To: <j2td88673cd1005091132t7a8c9a73i4a22e993de4aa78d@mail.gmail.com>
Content-Type: text/plain; charset="us-ascii"
Some of those items would not have been my first choice for running
problems. Keep in mind allot of mechanics that do not specialize in
Vanagons have no idea how they are supposed to run so I'm sure your
instincts are correct in that it is not running right. Here is a good
article to start with:
http://www.van-cafe.com/home/van/page_9_9/vanagon_running_problems.html
Also, the next LOONG but thorough write-up is from Scott Daniel who was kind
enough to write this down 2+ years ago when my van was having problems. It's
long but it covers all the bases. Plus it will keep him from having to type
it in again :)
" I would so love to write the definitive troubleshooting steps.
I can not say enough 'check the basics.'
Like pretend I wrote that 5 times always, always check basics really
carefully first - like compression, fuel pressure, inspect spark plugs etc.
Btw...there's an old time rule ( I've been working on cars of all types 44
years or so ) ..it came from the carb days, but it still applies :
( this is for gasoline, not diesel of course )
Mechanical condition of the engine first ( compression, valve timing,
timing belt if that applies, ....everything that is mechanical with the
engine.
Next - everything ignition. Like make sure that is rock solid.
Spark plug wires btw - they can be VERY nebulous - it they are old, or
cheap...you can work on a car for days and in the end it'll be spark plug
wires that were 'the thing' - some tricks - watch the engine run in total
darkness, you see tiny sparks running around - bad plug wires.
Another back yard spark plug wire test- light spray them with water while
it's idling, if it stumbles, bad plug wires.
Coils - coils don't usally fail. They just get old. I put a new coil on a
fine running personal car of mine one time - it ran 15 % better, and I
thought it was fine before that.
THEN fuel system.
Also, since it's electronic, this can't be said enough :
grounds, grounds, GROUNDS.
Electronics can be nebulous too. The actual electronic components are very
robust usually, like the ECU. I seldom find a bad one.
But how the wires contact, or how the wires themselves are- wires get old,
grounds corrode.
Here's another 'rule' :
This is a Scott Foss-original ( that's me, Scott Daniel Foss ) 'Rule' -
WHERE ANYTHING MECHANICAL INTERFACES WITH SOMETHING ELECTRICAL OR ELECTRONIC
- that's a weak area .
Points are an example. A phonograph needle is an example.
Switches arcing and wearing are an example.
So.....the biggest mechanical/electronic/electrical interface in a vanagon
is the Air Flow Meter.
Moving parts, and a mechanical sweeper, like a fuel gauge sender - it can't
work indefinitely- though they do hang in there well. Its mickey mouse in
modern times even.
It's a weak link.
All modern cars have an air mass meter, no moving parts- a huge leap forward
in about 3 ways over an AFM. Compensates for humidity, barometric pressure,
etc. - an AFM can't do anything like that - it's very dumb in comparison.
Plus it has a mechanical sweeper that wears. There's a trick about
rebending the sweeper to contact a different area of what I rubs on. The
spring tension on it is adjustable somewhat in some AFM's but that's not
something you'd ever change. It's not recommended to go messing around in
there. They're a bit sensitive, and if tired, they're just tired. Best is to
have a couple good used ones to play with.
(to give you an AFM story- had this customer's 87 syncro- at right around
3.200 rpm it would not quite miss or stumble, but it was uneven. Many people
wouldn't' notice it. I noticed that the way the power curve and gearing
was, you always ended up driving it form 3,000 to 3,500 rpm, and often right
at 3,100 to 3,200 rpm.
I was hesitant about a 500 dollar AFM,, but we found other major reasons for
vibrations decelerating from 52 mph, and the customer just like to invest
money in it, and we ended up doing a rebuilt trans, repairing a broken off
engine mounting stud, a clutch, a driveshaft, and a starter and after all
that, hey, why not an AFM too, right ? And it ran dead perfect after that.
The AFM was worn and faulty. )
Also....back to the 'it's a blockage of fluids or electrons' - check your
air intake boot. Those last really well too, but need to make sure that's
not it.
Exhaust leaks 'don't usually' make an engine run incorrectly., They can for
sure, but it's not like 'if it has exhaust port leaks it can't run right' -
it can run fine with those, but of course, false air-exhaust to the O2 can
throw it off.
And....02 is not involved in starting and WOT ( wide open throttle ),
Though I've read about people finding a shorted 02 wire as 'the cause' of
poor running - and that would make the ECU stumble.
( Never have encountered that myself, but it's possible. )
And there are a lot of checks in Bentley to do too.
Resistance checks.
Also....coolant temp sensor - SO MANY times hard starting or dodgey running
has been traced to poor connection to one of those.
Can't say that enough either.
So that's all needed - the orderly procedure of testing starting from the
basics, like maybe 40 to 50 inspections and tests.
And then these 'rules' .
And some things you simply can not test, like an ECU, other than to try it
in another vanagon, or put a known good one in yours.
I get all the components 'extra' at pick n' pull junkyards, try them right
away, and if they're good, I put a number on them, so I know if I'm running
# 1 or # 2 ECU or fuel pump, etc.
"
Bryan
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Lucky7Steel
Sent: Sunday, May 09, 2010 2:32 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Help with stalling van
Hi folks,
I'm wondering if anyone has any ideas.
My Vanagon (85) has lost it's mind i think.
I'll list below what i've recently changed but i could use some suggestions
as to what else to look at.
I honestly can't remember what the original issue was a few weeks ago but i
think it was losing power when driving.
Now, post all this recent work, it's driving like it's pulling another truck
behind it and today it cut out when i was accelerating again! My mechanics
think i'm crazy because they drove it and it was fine the other day. she
ain't super fast but she usually has a bit more gusto going up hills!
here's the list:
flushed engine
changed filters
spark plugs o.k.
replaced rad thermo switch
cool lev sensor replaced (system bled)
changed 2 relays (fuel sys and forget...ignition?
replaced fuel pressure regulator
checked gas pedal (needed to be re-secured)
cleaned starter motor connections. (starts right off now)
help???
~karen~
"baby" 1985 Vanagon GL