Because the warmed up engine has a lot of residual heat remaining in it. If the ambient temperature is say 67 at night, then your car will cool down to that point. However, when it warms up to 90 in the day time, the block does not warm up very much. A little, a little more if you would open the hood and let the sun shine on it. And most any old Benzs just won't start without a healthy set of glos. That is why I said replace all five of them and be done with it. You probably have 2 or even three plugs that have a little life left in them. If you like screwing around with it, replace only the two that are totally dead, and a bit later you can do the whole thing again.

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Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!