Date: Wed, 3 Aug 2016 14:20:28 -0700
Reply-To: Scott - IMAP <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott - IMAP <scottdaniel@TURBOVANS.COM>
Subject: Re: Bucking/Loss of power on HOT days
In-Reply-To: <CAB2RwfiHGd8idi9WOaaH4nDCBTd-cV7HXo7pKELHCc=r4YdBOQ@mail.gmail.com>
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there actually was a an engine compartment fan ..
fitted to some Datsun 280Z sports cars ...
aimed at the fuel rail area.
a factory fix just for this issue. a Bit dorky, but works.
On 8/3/2016 1:43 PM, Neil N wrote:
> On my '81 with Jetta 2.0, a similar thing happened. The fuel pump has
> always been prone to being noisy ( new at time of swap as was tank etc.)
> but would always get louder on hot days especially if climbing a
> steep grade for any amount of time.
>
> On a trip through a desolate area, with my fuel pump screaming away, I
> pulled over, let engine idle. It sputtered and died. It felt like vapour
> lock. It wouldn't start so I pulled the gas cap and heard a "whoosh" of
> air. With cap off, engine started. On a spare gas cap, I removed a little
> material to help allow tank to pull in ambient air. Not sure if this helped
> but no more stalls. I swapped in a used charcoal canister after that and of
> course reinstalled the other gas cap.
> AKAIK, my fuel pump hasn't been that noisy since.
>
> My swap uses the Jetta charcoal canister purge valve which is
> quickly cycled open closed by the ECU. Does the obd1 Suby swap use a
> similar valve?
>
> At one point I wondered if my different purge valve system pulled more air,
> over a given period of time, than the OEM design. i doubt it though. Even
> if it did, the charcoal filter should vent to atmosphere right?
>
> On my swap the fuel hoses likely pick up heat in engine bay but then I have
> to imagine that the WBX fuel hoses being so close to the engine case, would
> also allow fuel to pick up heat.
> OTOH, I can't recall if the WBX return hose is above the WBX engine.
>
> I'd be curious to see how your Suby swap would work with a fuel tank having
> the 12 mm outlet.
>
> Neil.
>
>
> On Wednesday, August 3, 2016, Richard Koerner <rjkinpb@sbcglobal.net> wrote:
>
> Am having bucking and loss of power on very hot days.
>> My van is an 85 2WD (233,000 miles), manual tranny, with a 2.2 Subie
>> engine (recent conversion by California Westys in San Diego), .....
>
>
>> The symptoms are classic "vapor lock"; yes, unusual with pressurized fuel
>> delivery on fuel injected engines, but I've been going through the List
>> Archives and there have been cases resembling vapor lock.
>> Typically, everything runs fine at freeway speeds in hot conditions; the
>> bucking problems start when I pull off freeway and have to contend with
>> stoplights and idling and low speed.
>>
>> This has happened at low elevations but hot (Florida and Laughlin, Nevada)
>> and also at high elevations (Gunnison, Colorado) on a warm summer day.
>> Problem disappears when van is allowed to cool overnight; starts fine and
>> runs fine the next day.....until it gets hot outside and van is moving slow.
>>
>> Mild whining (not screaming) from fuel pump when this happens. I suspect
>> some cavitation and pump damage occurred. Anyway, I've replaced fuel
>> pump....
>
>
>> Other things I've read about include: gas cap, charcoal cannister, bad
>> coil, fuel pressure regulator, bad ignition coil.
>>
>>
> --
> Neil n
>
> Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
>
> 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
>
> 1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>
>
> Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>
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