I tip my hat to Jmac the legend again .

[Sunny43.5]

Well today the work van was going fine then I made a stop at a customers home , when the van was restarted it was running on 3 cylinders . Turned it of and on again to see if it would fix itself [ yeah sure it will sunny ] but alas no, still running like a hairy goat . So drove towards home dreading the thought that it might be a blown head gasket and water had leaked into a cylinder while it was stopped .
Jmac's shop is on the way so a quick stop to see if he can help , lo and behold he quickly tells me without even looking at the van that the plug leads had failed . Apparently as he had serviced the van a few weeks ago and had changed the plugs [ okay they were about 8 years old and never been changed since then ] he told me that the leads would overheat and fail because the new plugs were drawing more power causing resistance . Picked up new leads and proceed to change them Yay problem solved , van back to normal . Now here is where I tip my hat to all you mechanics , Jims diagnosis was spot on but anyone of you who work on these vans must sometimes wonder what the bloody hell were the designers thinking . Just to change the plugs must have been an absolute mongrel to do as two of them are under the intake manifold which runs across the top and front of the engine . Changing the leads geez don't start me what drug was the designer on ?? I think if I had to do the leads again I might consider pulling the engine OUT what a nightmare . So to Jim and all you other guys I tip my hat

[Transporter]

Not just on your T5. Many later Japanese V6 engines and also Commodores have the spark plugs buried under the intake manifold which needs to be removed to get to the plugs and leads or coils Sunny. Yeah, they design them for easy manufacture, not servicing.

[Lucas_R]

I recently changed the spark plugs on my uncles Lexus IS250 which required removal of the inlet manifold to access 3x of the plugs. Ridiculous design.