Engine misfiring!

#1

My car “misfires” (that is, skips a beat) when I am either idling or trying to accelerate quickly and the car is in a high gear (that is, the rpms are low and the car has to work hard before the transmission downshifts… Any ideas about what the problem could be? I have been told that it might be a bad spark plug…

#2

Sorry! Forget to tell all what kind of car I am talking about! It is a 2002 Ford Taurus (V6 - 24 valve DOHC). Thanks for the help!

#3

Have you tried a tune-up yet?

#4

It could be a bad plug. It also could be a bad plugwire.

#5

No, I haven’t tried a tune-up yet… Do you think that would solve it? I am not sure what a tune-up involves, but I don’t want to get one if it won’t address this problem! Would a tune-up check the spark plugs and plug wires (as Cougar suggests)? I would assume so… (especially if I asked my mechanic ahead of time…)

#6

There are a number of things to consider. The first thing I like to do for a misfire is to change the spark plugs; especially, if they have been in there for years. Cost for changing all the spark plugs on a V6 (or, V8) can be expensive because of the difficulty of getting to the plugs. Therefore, use the engine code set by the check engine light, to determine if a particular spark plug may be at fault. If just one, or two, are the cause, you could just have those changed.
The code from the check engine light tells which engine cylinder is misfiring. You can have the engine computer scanned and get the codes. Many auto parts stores will do it for you. Just ask. Then, bring the codes here for advice.

#7

A tune-up should include new plugs but not necessarily will it include new plug wires. Going by the age of the car there may be close to 100k miles on it now and if so changing the plug wires out would be a reasonable thing to do even if they aren’t the trouble.

#8

There are two kinds of things you need to do with a car to keep it on the road. One is called maintenance. The other is called “repair.” A “tune up” is basic maintenance and should be done - not to “repair” a problem (though it could) - but just to keep the car healthy and in good shape.

I’d suggest that you pull out the owner’s manual, check all of the recommended maintenance stuff that you haven’t had done, and find a good local mechanic to bring all of the maintenance up to date.

While s/he is at it s/he can figure out out whether or not something might also need to be “repaired.”

But a huge number of misfires are just from lack of maintenance.

#9

a tunne-up would replace the plugs and probably the wires. My guess is it is the wires, plug wires that is.

#10

First off do not self diagnose but educate yourself. You likely will be sold a tune up (maybe needed maybe not) beyond the true fix. Make sure to describe the symptoms and ask to have it fixed. You tell them to do a tune up you may still have a poor running vehicle. Never suggest anything at first, you mislead the tech.