Update on my previously discussed problem:

The fuel pump continues to run quietly. While it has not been nearly as hot
as when the original problem of dying while idling (as in stop-and-go
traffic), I am still experiencing the stalling at idle. The engine otherwise
runs fine. Start up is a bit rough and sometimes requires that I blip the
throttle. So, my list of items to check in troubleshooting:

   1. throttle switch
   2. idle control valve
   3. O2 sensor
   4. fuel pressure

I will appreciate any thoughts on the above list of items. Am I neglecting
anything?

cheers,

mordo

On Mon, Aug 16, 2010 at 8:13 AM, mordo <helmut.blong@gmail.com> wrote:

> I have had the same experience about four years ago, Mike and here is why I
> don't think it is a simple particulate blocking the pump issue:
>
> When previously experiencing the filthy tank debris clogging the pump, the
> engine would bog down under load, particularly accelerating up hills. This
> makes sense when you consider the sludge will wash down toward the outlet
> and into the line. When one is just tooling along on level roads, perhaps
> the sludge settles back down away from the outlet. The only thing that made
> me suspicious of sludge blocking the pump was the gas from the filter
> appeared to be a bit rusty. I could not shake any debris out of the pump's
> filter screen, couldn't see any.
>
> The other factor that I may not have mentioned is that engine is running a
> bit more roughly than previously; sputtering a tad off the line, idling a
> bit more roughly.
>
> FWIW, I've driven about 60 miles since Saturday and have not had the
> whining and have not had  it die at idle. Go figure.
>
> cheers,
>
> On Sun, Aug 15, 2010 at 8:34 PM, Mike <mbucchino@charter.net> wrote:
>
>>  It may be fine in all other respects, and still be cavitating or
>> restricted enough to be quite noisy.
>>  I just removed my pump for cleaning and hose/clamp replacements (thanks
>> for the replacement pump, Craig C!), and when I shook out the remaining fuel
>> into a rag, I couldn't believe the amount of crap caught in the pump's
>> internal pre-filter screen.  I never even knew that it had a screen in the
>> large inlet side, but it makes sense.  It's fairly fine, and only very small
>> particles will pass thru to get caught in the filter, which is after the
>> pump.  The pre-filter pump was eliminated by VW, possibly due to noisy pump
>> operation once restricted due to particles.
>>  You can run it polarity-reversed to flush it out backwards through a rag
>> into a bucket.  Craig told me (at the Terryville show today!) that he uses
>> denatured alcohol for this, so it leaves things clean and dry for storage of
>> a spare pump.  It's also less explosive than gasoline!
>>
>> Mike B.
>>
>> --------------------------------------------------
>> From: "mordo" <helmut.blong@GMAIL.COM>
>> Sent: Sunday, August 15, 2010 1:39 PM
>>
>> To: <vanagon@GERRY.VANAGON.COM>
>> Subject:      VERBOSE: fuel pump, ethanol, cavitation
>>
>>
>>  I'd be willing to accept that, Jake except that it does not exhibit the
>>> other symptoms of being choked. Like I said, it doesn't bog down when you
>>> mash the pedal. Previously when my tank was expelling crud, I would lose
>>> power when I accelerated up hill or to pass.
>>>
>>> I'm certainly going to pull the tank when I empty it. I have an original
>>> spare that is good shape.
>>>
>>>
>>>
>>> On Sun, Aug 15, 2010 at 12:40 PM, Jake de Villiers <
>>> crescentbeachguitar@gmail.com> wrote:
>>>
>>>  It sounds like your tank outlet is restricted.  That 'laminate trimmer'
>>>> noise only comes from lack of volume at the inlet side of the pump.
>>>>
>>>> Do as Scott suggests and run your pump from a hose into a gas can to see
>>>> if
>>>> that makes a difference.
>>>>
>>>> If the noise goes away, its time to replace the gas tank.
>>>>
>>>>
>>>>
>>>> On Sun, Aug 15, 2010 at 7:38 AM, mordo <helmut.blong@gmail.com> wrote:
>>>>
>>>>  O, List,
>>>>>
>>>>> I've been reading a lot of the discussion both here and on the Samba
>>>>> about
>>>>> fuel pump cavitation since I had a discouraging failure en route to the
>>>>> Outer Banks Saturday a week ago. I'd appreciate the collective wisdom
>>>>> of
>>>>> the
>>>>> list on this incident.
>>>>>
>>>>> Van is generally running very well tho' I was a bit apprehensive of my
>>>>> instrument cluster after tearing the foil thus worried that any warning
>>>>> signs won't be reported. So, traffic from Springfield, VA on 95S was
>>>>> hateful
>>>>> as usual and that day it was dreadful all the way to 295 interchange
>>>>> near
>>>>> Richmond. Dodged the back up on 64E by going down to 460E, wade through
>>>>> Norfolk area and on to NC 168/158 and am shortly mired in a hellish, 20
>>>>> mile
>>>>> debacle of too many damned vehicles all going to the same place. And,
>>>>> it's
>>>>> hot, hot, hot, approximately 99F "real feel" that day and the rad fan
>>>>> is
>>>>> cycling on and off regularly and occasionally up to high speed (that's
>>>>> a
>>>>> surprising sound). Stop and go, creeping, crawling with the AC on.
>>>>> About
>>>>> four miles before the bridge over the Currituck Sound, I hear what I
>>>>> interpret is a wheezing sound from the cooling system and the engine
>>>>> sputters to a stop. We pull over onto a grassy verge and curse the gods
>>>>> for
>>>>> their cruelty. I try starting again and it kicks over, runs momentarily
>>>>> and
>>>>> the sputters to a stop again. Wheezing sound was present again.
>>>>>
>>>>> After hassling with an ESL support operator at my motor club, I get in
>>>>> to
>>>>> tell the operator the VIN. I crank it over again just for kicks and it
>>>>> starts and runs normally. So, I say, "Never mind, it's running again.
>>>>> I'll
>>>>> call if I need a tow." We drove about 200 yards and kaput. Try to start
>>>>> again and it sputters and coughs and kaput. And then the starter won't
>>>>> crank
>>>>> over. Wheezing sound again. After a long, hot ride in the tow truck cab
>>>>> (three people plus driver) we are at our destination and I ignore the
>>>>> van
>>>>> in
>>>>> favor of several anodyne adult beverages.
>>>>>
>>>>> Next day, I start it and run it and discern that the wheezing is a
>>>>> noisy,
>>>>> whining fuel pump. It was an aftermarket pump, about three years old so
>>>>> I'm
>>>>> willing to believe that it is failing. So, I order a replacement from
>>>>> BusDepot. Replace it and the filter. The old filter bled rusty-looking
>>>>> fuel."Hrmmm," says I. Starts rough but eventually runs fine. On the way
>>>>> back
>>>>> to Baltimore, I start to get the whining fuel pump sound again and
>>>>> occasionally, idling at stop lights, the engine quits. Restarts
>>>>> normally
>>>>> and
>>>>> runs well at high speed, pulls strong all the way to Baltimore. So, to
>>>>> summarize:
>>>>>
>>>>>
>>>>>  1. Hot ambient temps
>>>>>  2. fill up in southern Virginia with 10% ethanol fuel
>>>>>  3. fine rust in fuel filter before replacement
>>>>>  4. new Bosch pump still have whining sound
>>>>>  5. Engine runs well under load, acceleration normal
>>>>>  6. Sputters at hot idle and sometimes quits
>>>>>  7. cleaned the tank three or four years ago
>>>>>
>>>>>
>>>>> I have read of the theory that ethanol-blended gasoline is responsible
>>>>> for
>>>>> cavitation, its specific gravity being lower than straight gasoline.
>>>>> I've
>>>>> read the theory that the generic Bosch pump is too fast for gasohol and
>>>>> that
>>>>> a resistor in line on the pump is the answer. I have experienced the
>>>>> effects
>>>>> of cruddy fuel choking the fuel pump and my experience was inconsistent
>>>>> with
>>>>> previous misadventures. That usually presented as choking and losing
>>>>> power
>>>>> under load.
>>>>>
>>>>> What do you all think is the most likely culprit? I was under the
>>>>> impression
>>>>> that most fuel around the mid Atlantic was 10% ethanol but perhaps I am
>>>>> mistaken. I am suspicious of my fuel pressure regulator - haven't
>>>>> tested
>>>>> fuel pressure in a couple of years.
>>>>>
>>>>> Cheers,
>>>>> --
>>>>> mordo
>>>>> 1990 Carat
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> Jake
>>>>
>>>> 1984 Vanagon GL 1.9 WBX 'The Grey Van'
>>>> 1986 Westy Weekender/2.5 SOHC Suby 'Dixie'
>>>>
>>>> Crescent Beach, BC
>>>>
>>>> www.thebassspa.com
>>>> www.crescentbeachguitar.com
>>>> http://subyjake.googlepages.com/mydixiedarlin%27
>>>>
>>>>
>>>>
>>>
>>> --
>>> mordo
>>> 1990 Carat
>>>
>>>
>>>
>>> --
>>> mordo
>>> 1990 Carat
>>>
>>
>>
>
>
> --
> mordo
> 1990 Carat
>

--
mordo
1990 Carat