So I've determined that four of the glow plugs in my '85 300D are bad;
one had a resistance of under an ohm, but the others ranged all the way
up to some 1MOhm.

I go to AutoHausAZ to check things out, and they've got the Bosch
"pencil type, for fastglow system" plugs.  Performance Products has a
picture that looks "loop type," and they're about $3 more than the
AutoHausAZ ones.

Will the AutoHaus ones work in this car, if it's got a stock relay?  For
some reason I'm of the impression that the "loop type" went away during
this model series but certainly I could be mistaken...  The fuse in the
box is 80A, if it matters.  ...and I'm not certain that the relay is
stock, but the fastglow kit makes me think there's a box for four
cylinders and then "other stuff" somewhere else for the fifth...

thanks,
-tom!

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