Date: Sun, 8 Aug 2010 09:34:52 -0600
Reply-To: "Mike \"Rocket J Squirrel\"" <camping.elliott@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "Mike \"Rocket J Squirrel\"" <camping.elliott@GMAIL.COM>
Subject: Re: Mystery engine cutouts
In-Reply-To: <16384.75635.qm@web83606.mail.sp1.yahoo.com>
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All the helpful comments about Mellow Yellow's recent problem got me
focused on temperature possibly being a cause for the problem. Summary:
climbing up several summits earlier this week on a very hot day, the
engine would lose power briefly (3 to 4 seconds) then power back up again.
I swapped out the ECU the next morning and drove home over two more
similar grades in much cooler temperatures without incident.
Loss of ignition? The tach said no. The O2 monitor showed full lean
condition and the full lean condition suggest a fuel delivery problem.
Bad fuel? I was running on a new tank of gas from an unfamiliar station.
I'm going to look at the intake side of the fuel filter to see if there
are any traces of water.
Vapor Lock? This was suggested but I wonder how hot it would have to get
in the engine compartment to vaporize fuel in the pressurized fuel line.
Failing fuel pump? Could be. A remote-reading fuel pressure gauge or a
microphone on the pump could be used to check, but that's getting a bit
complicated.
Bad ECU? David Beierl suggested looking at the drive to the fuel pump
relay to see if the ECU got weird and shut off the pump briefly. Some
wire and a light bulb would suffice for that.
I want to toss out an additional bit of information that has occurred to
me: Mellow Yellow has been driven in similar conditions (hot weather,
long uphill grades, engine under full load) in the past without problem.
But about three weeks ago it got hit by a '72 baywindow bus when that
bus was struck from behind by a speeding sedan. The passenger side
quarter panel is mashed in below the air intake vent and above the side
marker light by at least 1-1/2'' (3-4 cm) and I wonder if that has
substantially reduced the amount of outside air being drawn into the
engine compartment, leading to higher temps in there. The temp gauge
didn't indicate excessive heating, but things like the ECU might have
been getting baked.
Just an idea.
IN OTHER NEWS, The insurance company for the driver of the car that ran
into the baywindow (the guy that caused the collision) has told the
owner of the baywindow that they are not going to be paying any claims
because the driver swerved to avoid an oncoming car so was not at fault.
Police report cites him for "careless driving." He verbally said that he
was looking down when driving and when he looked up he saw the oncoming
car. Whatever. It's not clear to me how the insurance company doesn't
feel it needs to pay for damages when their driver was driving
carelessly. I've been out of town and will talk to that insurance
company claims adjuster tomorrow.
--
Rocky J Squirrel
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
Bend, OR
KG6RCRs
> --- On *Fri, 8/6/10, Mike "Rocket J Squirrel"
> /<camping.elliott@GMAIL.COM>/* wrote:
>
>
> From: Mike "Rocket J Squirrel" <camping.elliott@GMAIL.COM>
> Subject: Mystery engine cutouts
> To: vanagon@GERRY.VANAGON.COM
> Date: Friday, August 6, 2010, 10:54 AM
>
>
> Okay, so on my trip of nearly 2,000 miles of travel from here to
> Flathead Lake, MT. and back, something very strange happened yesterday.
>
> I filled up with gas in Pendleton, Ore., and turned south on highway
> 395. There are four or five summits to climb between Pendleton and John
> Day, Ore., my night's destination.
>
> It was a hot day. I was climbing the first steep summit in 2nd gear
> (auto tranny) at about 3800 rpm - this is my usual steep climb routine.
> Suddenly the engine cut out. After about four seconds, it came back to
> life. It did that two more times before reaching the summit. It did that
> going up each summit thereafter.
>
> The timing between cutouts was anywhere between 30 seconds and 60
> seconds. The cutouts only lasted three to five seconds, but that's
> plenty long when climbing up a steep grade.
>
> There may have been cutouts on the flats, but I didn't feel them.
>
> In all cases, I was in 1st or 2nd (depending on grade) with engine
> between 3,000 and 3900 rpm.
>
> Every time it cut out, my O2 monitor display shot over to the left,
> showing the exhaust mixture was completely lean. Like the fuel had been
> cut off.
>
> I was a nervous wreck by the time I reached camp, worrying about the two
> more climbs between me and home I had to drive today.
>
> I didn't sleep well. But today, it did not cut out once, the climbs were
> of the same difficulty.
>
> Here's what was different:
>
> 1. Before starting out this morning, I swapped in a spare ECU.
> 2. The day was 20 to 30 degrees (F) cooler than yesterday. Yesterday I
> was seeing 95F in the cabin.
> 3. I had a new tank of gas.
> 4. I sprayed WD-40 on the various springs and pivots and hawsers and
> pulleys on the throttle mechanism -- the throttle didn't feel to the
> hand like it was moving smoothly after several hours of dusty dirt road
> grime on it.
> 5. I checked the skinny little vacuum lines (1.9L) feeding the timing
> advance stuff on the dizzy and they looked fine.
>
> Too many things changed to be sure what the problem was and what fixed
> it. I didn't want to spend the day tinkering, just wanted to get home.
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