New Platinum 4 plugs, 4K

[John Larson <jdlarson@ix.netcom.com>]

"I did a tuneup 20,000 miles ago, so the plugs didn't really need
changing"? ANY new plugs should have made a difference. Professionally,
I wouldn't let my customers with a car of that vintage go more than 10K
between tuneups. Maybe 15K if the engine was relatively freshand they
did a lot of freeway driving. The plugs deteriorate by then, the cap and
rotor need to be inspected, the O2 sensor checked, filters changed,
wires tested, and all those little (but important) things like vacuum
lines, mixture settings, injector seals, valve cover gaskets, and
breather elbows need to be checked and their performance monitored
and/or rectifiedLonger intervals have the potential of putting undue
stress on the emissions system, specifically the catalytic converter. 20
K is pushing it, IMHO, and to mention it as if it were merely a point in
a longer interval seems even worse.
John