CJ:

These particular holders have a multi-spline rather than a hex nut. Older ones have a hex nut below the injector line cap nut. I borrowed the tool from my indy mechanic, but I think it is available for about $20.

Diagnosis:

Engine misses on one or more cylinders at idle, runs much better above 1500 rpm. Usually worse warm. VERY rough idle -- shakes car hard.

Hard knock on affected cylinder, goes away when line bled. No or little change in idle when line bled.

Fuel spill normal when line open!

Injectors OK.

Oil consumption is normal.

Fuel consumption normal.

Compression OK (not necessarily better than that!),

Valve adjustment OK or hydrualic tappets OK.

No unusual smoke at idle (hard to tell on cars with trap oxidizer or catalyst).

Think of it this way -- what would make the pump deliver fuel but not delelop enough pressure to open the nozzle and actually inject it?

What is going on is that the fuel is leaking back into the pump body rather than pressurizing the delivery line. At higher speeds, the leak is small enough that some fuel is delivered and burns more or less normally. At idle, the leak is large enough that the pintle in the nozzle won't lift on time, leading to very late injection and knock, low power, and hard shaking.

Naturally, a bad IP set will do the same things but it won't recover nearly so much at speed.

And it just seemed very likely to me that it was the problem. First thought I had when I saw the car and listened to it, in fact!

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!