Date: Mon, 3 Sep 2012 15:30:35 -0400
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: '87 Westy 2.1L, Running Rough, No Power, Dies at Idle (Long)
In-Reply-To: <COL125-W154971FE85B96F78F48605CFAB0@phx.gbl>
Content-Type: text/plain; charset="US-ASCII"
If it runs fine cold but goes rich after warm up you could have an O2 sensor
or wiring problem. The simple test when it is choking and hacking it to turn
the ignition off and back on. If the symptom clears for a short while then
the o2 sensor wiring is the problem. What to check?
The green wire to the sensor is a coaxial shielded cable. Peel the cover
back to see the outer shield. With the sensor disconnected, ignition on,
check the center lead and outer shield for voltage. Measure to the chassis.
Form the center wire to the chassis there should be ~.5 volt. From the outer
shield it needs to be really close to "0". From the center lead to the outer
shield should be the same voltage as from the center wire to the chassis.
If the center wire shows near 0 it is most likely shorted within that green
cable. If the outer wire has voltage or does not give a full reading when
checking from the center wire to it then you have a ground or wiring
problem. The O2 sensor ground reference is shared with the distributor
harness. Follow the wires to the distributor pick up coil. Look for the
brown one. They are often connected at the base of the oil breather tower.
The plastic tower makes for a lousy connection. Move it. Make sure the wire
and crimp is in good condition. Any voltage drop here gets added to the
signal the ECU is looking for from the O2 sensor. Since the sensor can only
develop ~.8 volt or so a .5 volt drop can be real problem as it will cause
the ECU to just keep richening up the mixture looking for that signal.
BTW I am surprised that a shop would go through the trouble of replacing the
cat and muffler and re use the O2 sensor. Now that you've done the super
duper rich thing that cat is somewhat damaged.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike Finkbiner
Sent: Monday, September 03, 2012 2:59 PM
To: vanagon@GERRY.VANAGON.COM
Subject: '87 Westy 2.1L, Running Rough, No Power, Dies at Idle (Long)
I have had my '87 Westy for quite a few years now, and while I have had some
adventures, I haven't had to be towed before. It's a standard 2WD, with a
Boston Bob 2.1 liter engine and 4-speed manual.
Yesterday I was headed north, and about thirty miles out of Moscow it
started to lose power. The engine wouldn't rev up, and started to surge and
drop. Pressing the pedal all the way to the floor didn't do anything, and I
couldn't rev up in lower gears. I pulled off and as soon as I got off the
gas, it died and I had to re-start. I also seemed to smell gasoline.
I sat and thought for a couple of minutes. Earlier this summer a mechanic
had gone through it while looking for a power steering leak. He replaced
the fuel filter, and I ended up with a new power steering pump, PS filter,
and a wrecking yard high pressure line.
Then I drove several hundred miles, to the Puget Sound area, back across the
North Cascades highway and home with no problems except a noisy muffler,
getting about 18mpg. I knew the catalytic converter had been rodded out,
and when I ran into a sale on an OEM muffler and cat, I decided to replace
them both. The shop which did the work had a lot of problems getting the
oxygen sensor out of the dead cat, but it seemed to run fine around town.
So, after I pulled over I popped the engine lid and re-started. It seemed
to be fine, but then after a couple of minutes started running rough. I
gave it some gas and got a puff of black smoke out of the new tailpipe. I
shut down, and disconnected the O2 sensor to run on the default mode. After
that it seemed to run OK idling for a few minutes, and I could rev the
engine with no problems. No more black smoke. I left the O2 sensor
disconnected to see if that was the issue.
I got back on the road. For the first five minutes things were fine, but
then - it started losing power and doing the surge/dip thing. I pushed on
to the next little town, about five miles away, maxing out at about 45.
When I pulled off the road it died again.
Towed home on a flatbed it ran fine driving it into the garage.
Terry K suggested the throttle position switch, so, this morning, on a cold
engine, I dug into that. It had zero resistance at full throttle, full
resistance through the mid-range, and also at idle. So, I took the throttle
body off, cleaned it up and found that switch would close at idle if you
jiggled things. I slightly bent the U on the end of the arm so it touched
the cam more fully, and it now works fine, full resistance at idle and full
throttle.
After re-assembly it idled nicely, at about 950, engine sounding smooth. I
let it warm at idle and drove a few blocks. Ran fine, dropped to idle at
stoplights, etc. The temp was still a bit below the LED and oil pressure
above 40, so I took it on the highway. After three to four miles, the temp
was up and I started up a bit of a hill. The engine started surging a bit,
and felt down in power. Over the top of the hill it was definitely surging,
so I pulled over and it wanted to die until I gave it some gas.
Headed back into town at 55, mostly pretty flat and it did the surge/drop
thing a fair bit, but kept running. In town it wanted to die at stop
lights. With the window down I could hear it running rough. When I got it
back into my garage it would run, but rough, as if one or more cylinders
were cutting out.
I let it cool down a bit, and drove a few blocks in town. It got worse, had
no power, until I shut down and re-started, then ran rough back to the
house.
Hmmm.
If you have any suggestions, please PMail me as well as the list. I read
this in Digest mode.
Thanks!
- Mike
Mike Finkbiner
'87 Westy
Moscow, ID
mike_l_f@hotmail.com
Happiness is a moving target
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