First prize in long-distance engine diagnostics to Jake de Villiers for
identifying the fule pressure regulator as the culprit in this misbehaving
engine.

A new part solved the problem and as an added benefit, the engine idle is
now stable at 950 rpm. Previously, the idle speed wandered slightly, +/- 100
rpm.

Hooray!

On Sun, Nov 7, 2010 at 1:48 PM, Jake de Villiers <
crescentbeachguitar@gmail.com> wrote:

> It sounds as though your fuel pressure regulator has failed.
>
> When the internal diaphragm goes, the injectors see full pump pressure (~
> 70 PSI) instead of the ~35 PSI they need.  You can hook up a gauge at the
> test port provided or just go ahead and replace it - they aren't expensive.
>
> Good luck!
>
>
> On Sun, Nov 7, 2010 at 10:00 AM, mordo <helmut.blong@gmail.com> wrote:
>
>> Greetings, Volks.
>>
>> I find myself relying on La Vana Blanca as my daily driver for a bit while
>>
>> the company car is in shop awaiting repairs. The cooler weather seems to
>> have brought on a new fuel system problem in the van. There is so much
>> written about idle, fuel mix, temp II sensor, etc. that I find it
>> difficult
>> to parse pertinent info. Will appreciate any clarity that can be offered.
>>
>> The engine starts readily from stone cold (in the mid 30sF here at night)
>> but the idle is very rough. Almost feels like only 3 cylinders are firing.
>> After 3 minutes of trying to nurse this idle smooth, the van will drive
>> but
>> only with severely diminished power and lots of smoke from a way too rich
>> mixture.
>>
>> If during this initial cold start, I disconnect temp II sensor the idle
>> smooths at about 1000-1200 rpm. However, I cannot accelerate and drive
>> with
>> temp II disconnected - the engine bogs down and sputters badly.
>>
>> After about five minutes of nursing the throttle and chugging along, the
>> engine will suddenly smooth out and drive reasonably well though somewhat
>> under-powered. But it is certainly firing on all cylinders. Not nearly the
>> pick-up and power as normal. It will idle at stop and generally behaves
>> alright.
>>
>> Fuel economy is miserable - about 75 miles to the half tank at the moment.
>>
>> Fuel smell is strong; the engine is surely running rich.
>>
>> Temp II sensor is about 6 months old. Plugs are about 3 months old. Fuel
>> pump and filter, likewise 3 months old.
>>
>> This seems like a faulty temp II sensor based on a lot of what I read but
>> also suspect the TPS.
>>
>> 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