Just bought a '95 300D for what seemed like a very good price. It has 200K miles. When the guy started it up for me, it idled smoothly. After I bought it and drove it for a few minutes, it started missing at idle. Goes well above 2000 rpm, on the freeway, etc. and seems to have adequate power once it's spooled up. I let the car sit overnight and when I started it up cold again the next morning, it again idled smoothly until it warmed up. Maybe not perfectly smoothly but a lot smoother than when it was warm.

I hit each exhaust runner with an IR pyrometer and the rearmost cylinder is almost always 10-20 degrees cooler. I assume this is the problem cylinder. I don't think compression is bad because when the car cranks, the pulses are all perfectly even.

I am going to start by putting a new fuel filter on and filling it with diesel purge and also adding some to the fuel tank. Any other suggestions? If I have to remove the injector, how hard is that once the intake is off?

Thanks,

-David

Maybe you could crack open that inj. line while running and see if it get worse.

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1987 190DT, clackity clack
90 Mustang track car
95 Lightning

If I just brought home a 95 e300d with 200k, and the following repairs had not been done recently (within the last 20k miles), I would first:

Clean fuel tank and strainer
Replace fuel filter (and pre-filter)
Rebuild injectors (diesel purge works beautifully...for a short while. It is a complete waste to put it in the tank.)
Replace vacuum pump
Replace tensioner pulley spring and shock
Replace coolant with G-05
Replace expansion tank cap
Check glow plug operation

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2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

Replace engine mounts
Replace brake hoses, pads, and rotors

__________________
2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

>>the rearmost cylinder is almost always 10-20 degrees cooler.

OM606?

If so, check the compressions sooner rather than later in your list of work to do.

Sorry, but, these are classic symptoms of inlet valve seat recession, which affects the rearmost cylinders of this engine.

Another way you might see it is by starting the engine from cold with the inlet manifold removed and the vac pipes plugged - you don't want to see any exhaust smoke chuffing back out of the ports for No 6. Alas, I did!