Relating this tale in part to illustrate how blind to the obvious one can be sometimes. 

Over the winter I noticed the van took more turns with the starter to run. Back then I did do the  electrical tests outlined in Bentley to see if some sensor or something was awry. But everything was in spec. 

B me over the last few weeks the van would sometimes take quite a few tries with the starter to fire up. I couldn't make out any real pattern, sometimes it would fire right up, sometimes I would have to crank and crank.

If I was forced, I would say it happened more often with the engine warm.

Once started the van ran normally, good power etc. I wasn't happy with the idle though, seemed rougher than normal. 

So the last few days were spent tracking the problem down. I checked fuel pressure and all tests passed. I checked spark plugs and replaced 2 year old plugs with new. Checked distributor rotor and hall sensor. Checked the D15 connection at fuse panel ( I had fixed that a while back). Lucky I did pull the fuse panel as I found a very iffy connection at my low beam relay.

Then I went at the connection box in the engine compartment, left hand side. My van had the bbw46 heater installed. I had pulled the nonfunctional heater unit and plumbing but the wiring was still in place. The heater system has two fuses and a big relay in that box which made the box even more of a rats nest than normal. I checked the connections, black wires, that feed the coil, idle system heater, and ecu relay. The wiring to the connections was hard and the connections didn't look good. I cut back and replaced the spades.

All of the above did not fix the problem. Of course at that point I was cursing myself for not making one of Mark's test wire set ups. If I had I think I would have saved myself a lot of trouble.

I had my wife crank the engine and I measured voltage to the coil. I wondered if there was a voltage drop problem during starting. Well it was more than a voltage drop, it was a voltage absence during starter cranking.

I was stumped, I didn't see the obvious. While I was thinking, I cleaned out the idle valve with brake cleaner.

We have this hard to capture rooster that has taken to roosting at night under our bedroom window. So I was up at five this morning. And them it occurred to me, the ignition switch.

I got out a spare, and plugged it in to the steering column plug and turned it with a screwdriver. Engine started up immediately. Tried it again and again, engine started. Man, did I have egg on my face. I have replaced a few vanagon ignition switches over the years but overlooked it this time. 

Alistair