Thanks IChris...so in looking at the chart, I am guessing the times I am reporting corresponds to A on the graph in the 8 second or so range. I am a little confused by your interpretation of b as "Is safety shut off." Do you mind explaining a tiny bit more?

Last winter my pre-glow times corresponded more along the lines of the top (b) part of the graph.

__________________
97 S500 (90,000 miles) - wife's car
87 300D (298,000 miles and a replacement #14 head)
94 Suburban K2500 - need something to haul firewood
83 300SD (343,000 miles) (sold)

Basically A is when light goes off. B is when relay goes off.

Makes sense...I am a bit tired today so forgive me...that should have been obvious. In looking at the testing procedure in the FSM (http://www.w124performance.com/service/w124CD1/Program/Engine/602_603/15-4000.pdf), it does make mention in the table on the last page of testing a coolant temp sensor when the pre-glow light goes out too early.

Both my pre-glow light, and the glow relay turn off way too early. From what Sixto said, however, this doesn't apply to mine correct? Just want to make sure I am understanding correctly before I go out and buy another relay.

__________________
97 S500 (90,000 miles) - wife's car
87 300D (298,000 miles and a replacement #14 head)
94 Suburban K2500 - need something to haul firewood
83 300SD (343,000 miles) (sold)