Date: Sun, 6 Mar 2011 20:36:37 -0800
Reply-To: Jim Arnott <jrasite@EONI.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Jim Arnott <jrasite@EONI.COM>
Subject: Re: sometimes it just won't go...
In-Reply-To: <p06230900c999fc07e4b3@[192.168.1.104]>
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Hey John,
I'm hearing the description of a worsening vacuum leak. I'm be digging
out my propane torch and floating some propane over all the vacuum
leak possibilities looking for the one that speeds up the motor. (You
don't light the torch.)
Won't start? Get a dry set of plugs in it. Then check the fuel pressure.
I had a similar problem this weekend. Over the past half dozen fill-
ups I've watched my mileage decline from nearly 18-19 mpg to around
16. This weekend was warm enough to go find the problem. New plugs
because it was time and they were on sale. Last maintenance was about
six weeks ago. New air cleaner element and oil & filter. Have to pull
the air cleaner box and AFM to get to plug #1. Had to pull the same to
replace the element. (You see where this is going, don't you?) When I
pulled it last time, I managed to pull the S hose about 3/4 off the
throttle body. Massive leak. Lots of unmetered (and unfiltered) air.
There's where the fuel economy went. Put it back on and now the
engine doesn't die on rapid deceleration. I'll know next week if the
fuel economy is back where it's supposed to be. Betcha it will be.
You can follow Folly's fuel economy at http://www.fuelly.com/driver/jiminor/vanagon-2
Synopsis: massive unmetered air leak and it 'ran' just fine.
I'm thinking that you're going to find a similar issue.
Jim
More below.
On Mar 6, 2011, at 7:19 PM, Grungy wrote:
>
> Symptom: indicated idle speed on the tach changes while at idle
> (usually faster) and after that it gags if the gas pedal is
> depressed. If I let up, it idles again. Have to keep touching the gas
> pedal until it revs UP a bit instead of slowing, then I can go again.
> If I manage to stall it, it won't start again for a couple of
> minutes. Sometimes, while driving on the freeway or elsewhere, we can
> feel it stumbling - losing power, then catching up.
Unmetered air getting into the engine.
> What I've replaced so far: plugs, plug wires, cap, rotor, coil wire,
> fuel filter (previous all new) coil, idle stabilizer, exhaust from
> the J-pipe, including O2 sensor, cat and muffler. Going to dig the
> idle stabilizer controller out from behind the taillight in a few
> minutes.
Save your money.
> When it won't start, it's flooding, so there doesn't appear to be a
> fuel pump problem.
How do we know it's flooded? Wet plugs? If so, compression check, fuel
pressure check, new plugs. It DOES have spark, right?
> I've noticed a crack in the rubber hose between the intake pipe on #3
> and the air accumulator on top of the engine, but it doesn't look
> like it's big or deep enough to leak. Yes, that needs to be replaced.
Yes it does. Propane will tell you if that's your problem. I suspect
that it is a major contributor to the problem.
> I've checked all of the electrical connections.
> The only one that's loose is on the #2 fuel injector - it can slide
> longitudinally (where the other three cannot when locked).
This would just cause a miss.
> Cruise control has stopped working - and that might be related.
> Cruise tries to work - I can feel the gas pedal trying to hold itself
> down - but it slowly loses speed after being set.
No vacuum.
> The vacuum lines in the engine compartment look good, but I haven't
> checked beyond the 'firewall' to where the carbon cannister is
> supposed to be.
The vacuum line to the charcoal canister will likely not be your
problem Vanagons are surprisingly tolerant of small vacuum leaks. From
the above statement, you intuitively KNOW where the problem lies. Go
get a propane torch and find the leak.
