99 tiburon check engine light question

Maybe someone in this ng can help me out. My wife's 99 tiburon's check
engine light came on the other day. It started to run a little rough
and doesn't seem to have full engine power. On start up the light is
on steady, but after driving a bit it begins to flash. Once you stop
for a bit it goes on steady again. The owners manual says something
about exhaust gases being out of value? Anyway if anyone in this ng
ever had this problem with a 99 tiburon or other year I guess also
please let me know what it was. Thanks jimmy

 

Hi Jimmy-You most likely have an engine misfire. The fact that the CEL flashes
means the computer reads this to be a large misfire ans assumes gas is being
pumped throught the engine, only to be burned in the catalytic convertor. You
DO NOT want the convertor to burn gas, it can destroy the convertor ($$).
Pull the spark plugs and check for obvious signs of a problem, such as a
strong(er) gas odor that you don't smell on the others.
If this is the case, look closely at the plug wire for that particular plug for
any signs of cracking or burning of the rubber insulation. This may be very
hard to detect. Your spark may be shooting out a break in the insulation and
shorting to the engine instead of firing the spark plug. This usually happens
at the boot portion that extends down into the engine.
Aftermarket wire sets are about $40, I don't know what a dealer charges.
If you can't find a problem, this is cheap insurance anyway-especially if
you're over 60,000 miles or so.
Replace 1 wire at a time & move on to the next one as opposed to pulling all 4
at once. this way you'll be sure to get them back where they belong. (It's
easier to screw up than you'd think.)
Oh-when you're done, start the car. If the problem is fixed, remove the
negative battery cable for 10 minutes or more. This should turn off the check
engine light.