View Full Version : Changed Spark plugs...car run worse?

08-21-2004, 09:30 AM
I had my spark plugs changed, and the car runs worse..like it's going to blow up? he replaced them one by one, is there any other reason this is happening..I just want to drive it before winter comes...
The plugs are Motor Craft Platinum
and new wires too.

08-21-2004, 10:02 AM
Perhaps he cracked one of the plugs while installing them. Check them one by one to see if you can see any damage? Were they gapped right? Did you run a check for codes?

Still Crusin
08-21-2004, 04:55 PM
Also make sure wires were run correctly, fully seated on the plug and that the wires aren't touching something that's too hot for them like exhaust manifold

08-22-2004, 10:43 AM
With them done individually it is somewhat hard to mess up. You say the car runs worse. What is it doing or not doing? Does it run like it has a miss? If so with the car running go ahead and with an Insulated Pair of Pliers pull 1 wire at a time off the plug. You are looking for a change in idle quality. If it changes then that indicates the problem is not with that cylinder. If there is no change in Idle quality note which cylinder or cylinders you are having an issue with. Pull out the plug and check gap, cracks, etc.

Joisey Jim
08-23-2004, 01:08 PM
Look for a memory code, like #214. It may not throw a continuous engine light, but 214 (assuming the cam sensor is ok) would indicate a possible cracked plug insulator.

08-24-2004, 02:54 AM
I bet it is a bad wire. I got my car with 10k on a HG w/new dbl plats but same old wires... missed like crazy
did plugs, got worse
went through a drive through heard a tick-tick-tick sound
get out in the dark and looked and it was a badly arcing wire, i could see it illuminate the engine bay! ha!

new wires and it runs sweet =)

i'm running NGK Iridium and Bosch wires
great choice