Just wanted to follow up on this. Turned out that the Fuel Injector Pump
had leaky seals, so replacing them fixed the issue.

Thanks for getting me on the right track.

On Tue, Feb 6, 2018 at 5:10 PM, moritz schmid <schmidm90@gmail.com> wrote:

> I would start with the fuel filter. After that check for any leaks in the
> fuel system. If it’s warming up and the hoses start to expand that might be
> the problem. Clear replacement fuel lines can help to diagnose air bubbles
> getting in the fuel.
>
> Do you have the ability to plug it into a code reader? I TDI swapped my
> westy two years ago and kept the OBD port so I could plug Vag Com into it.
>
> On Tue, Feb 6, 2018 at 8:06 PM J.C. <dougm+sfbayrangers@kzsu.stanford.edu>
> wrote:
>
>> Question for the list. I have an '82, with a TDI engine swap, that started
>> idling rough. Quickly progressed to the point of dying (before warming up)
>> a couple of times. What I found peculiar was that, when I idled at a
>> higher
>> RPM (so the engine wouldn't completely die) the hesitation seeming would
>> repeat itself at approx 10s intervals. (And after it warmed up a while,
>> the
>> interval seemed to extend to about 20s.)
>>
>> I actually recorded this phenomenon in case it's helpful (or simply
>> interesting) in diagnosing the issue. A link to it is here:
>> https://soundcloud.com/user-359399352/rough-idle-consistent-repeat
>>
>> Might anyone have any pointers for helping me diagnose this problem?
>>
>> Thanks in advance.
>> ᐧ
>>
>