Cylinder 4 missfire
MrSandman
06-22-2006, 05:06 PM
Recently my SES light came on, so I took my car to Autozone and had them check it out. The error code it gave them was P0304 - clyinder 4 missfire. I guess that means I need to change my spark plugs and wires, since I haven't changed them since I've had the car. If that's the case, can anyone send me some info on changing the spark plugs in my car (a 99 GTP). Any help is always appreciated.
GTP Dad
06-22-2006, 08:23 PM
It is not hard to change the plugs and wires just hard to get to them. Start with the front and replace the wires one at a time. Make sure to set the gap properly and use AC or Autolite plugs. Don't use Bosch plugs. Also you may want to get a set of OEM wires from GM. You can get them from gmpartsdirect.com or rock-auto.com for a reasonable price. Once the fronts are changed you will have to either remove the dogbones from the front and rotate the engine forward to get to the rear plugs or risk some knuckles and use a ratchet with a u-joint to get to them. Rotating the engine is easiest but takes time and may require an engine lift to get it back into place. Good Luck!
gmtech79
06-22-2006, 09:58 PM
How many miles on the car?
wlkjr
06-22-2006, 11:26 PM
I just changed my plugs and wires last week. The rear ones will give you fits. Practically have to be a contortionist the get at them and Stevie Wonder can change them as good as we can. It's an ordeal by feel. I think no. 4 is on the rear too. I had 180,000 miles on my wires and plugs and the plugs still looked good and was getting 25 mpg. First tank after changing I'm still only getting 25 mpg. Most likely the culprit is a wire as I had three go bad in the first 6000 miles but none since. To remove the wires you really have to twist the boots around to break them loose so they will slip off. I got a great deal on some AC Delco wires from Rich (richtazz) and prompt service too.
richtazz
06-23-2006, 10:32 AM
Thanks for the endorsement Wally, good service is my goal. With a flex head ratchet and a wobble extension, it's easier, but the mechanics by braille is a little difficult, gotta do it by feel for the most part. Another helpful tool is a pair of ring-nosed pliers to get the old wires off. The heat shields make it a pain to get a grip on them with your fingers.
wlkjr
06-23-2006, 10:57 AM
Thanks for the endorsement Wally, good service is my goal. With a flex head ratchet and a wobble extension, it's easier, but the mechanics by braille is a little difficult, gotta do it by feel for the most part. Another helpful tool is a pair of ring-nosed pliers to get the old wires off. The heat shields make it a pain to get a grip on them with your fingers.
Both times I ordered parts from you I got them quickly. The service is excellent.
No way could I get any kind of removal tool on the back plug wires on mine. I just twisted and pulled the best I could. One of the plugs is right under some kind of sensor and it was the worst one. I did save a bunch of money though.
Both times I ordered parts from you I got them quickly. The service is excellent.
No way could I get any kind of removal tool on the back plug wires on mine. I just twisted and pulled the best I could. One of the plugs is right under some kind of sensor and it was the worst one. I did save a bunch of money though.
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