Defective spark plugs causing engine misfires?

Hazycrazy

Member
:
2003 Black Mazda Protege5
Hey fellow P5ers (and other car owners),

I'm having an issue with my P5 that's cropped up twice so far. My engine starts misfiring a cylinder, I take it to Mazda (Roger Beasly North in Austin), and they end up telling me I have a defective spark plug which Mazda replaces and sends me on my way. This first happened last July, and it was cylinder 3, this time (happened yesterday) it was cylinder 4. Actually, this time the service rep said the insulation on my plug had cracked.

Now the car has always run well, except for the 2 misfires and 2 times when it randomly stalled. I've had it since January 04, and I've put 21000 miles on it so far. I tried to get Mazda to do more than just replace the spark plug because I am sure there is a bigger underlying problem. They did replace the ignition coil saying it might have been overworking the plug, but I am sure they did that last time.

The first time this happened, the service rep said he believed it was a spark plug that was defective from the start, am I hitting a bad batch?

Should I just replace all the plugs myself?

I'm curious if anyone else has had similar problems? and how did you fix it?

or does anyone have some idea about what might be going on?

I feel like this is just going to happen again.

I appreciate any help you can give me.
 
yes replace the plugs yourself, just dont tighten the s*** out of them, and put ANTI SIEZE on them.
 
pdhaudio83 said:
yes replace the plugs yourself, just dont tighten the s*** out of them, and put ANTI SIEZE on them.

Any recommendations on what spark plugs to use?
 
just use stock OEM plugs.....get them for under $2 a piece.

whenever you have a problem with one plug, you should just replace all 4 becasue they are cheap....

-R
 
yup it's either your plugs causing misfiring or wires. but most likely plugs...
hmm..come to think of it..I need to change mine as well :)
 
Hazycrazy said:
Hey fellow P5ers (and other car owners),

I'm having an issue with my P5 that's cropped up twice so far. My engine starts misfiring a cylinder, I take it to Mazda (Roger Beasly North in Austin), and they end up telling me I have a defective spark plug which Mazda replaces and sends me on my way. This first happened last July, and it was cylinder 3, this time (happened yesterday) it was cylinder 4. Actually, this time the service rep said the insulation on my plug had cracked.

Now the car has always run well, except for the 2 misfires and 2 times when it randomly stalled. I've had it since January 04, and I've put 21000 miles on it so far. I tried to get Mazda to do more than just replace the spark plug because I am sure there is a bigger underlying problem. They did replace the ignition coil saying it might have been overworking the plug, but I am sure they did that last time.

The first time this happened, the service rep said he believed it was a spark plug that was defective from the start, am I hitting a bad batch?

Should I just replace all the plugs myself?

I'm curious if anyone else has had similar problems? and how did you fix it?

or does anyone have some idea about what might be going on?

I feel like this is just going to happen again.

I appreciate any help you can give me.
P5's rarely eat spark plugs, they do however like to eat coils..........strange....do you clean your engine often ? Rinsing it with water can cause the water to get down in the plug holes and give you all sorts of prob's. ie......cracked plug. As for your random stalling...........get the dealer to replace the egr valve.....we do lots........seems to work.........hope this helps.
 
mastertech said:
P5's rarely eat spark plugs, they do however like to eat coils..........strange....do you clean your engine often ? Rinsing it with water can cause the water to get down in the plug holes and give you all sorts of prob's. ie......cracked plug. As for your random stalling...........get the dealer to replace the egr valve.....we do lots........seems to work.........hope this helps.

No I don't clean my engine at all. As far as stalling goes, it happened twice, once a week before my first bad plug. The dealer told me the first time they thought the plug was just defective from the start, but I don't know. I'll replace the whole bunch to be sure, can anyone point me to a guide on changing the P5 plugs?
 
you need deep spark plug socket...I just don't remember which one...it's really easy to do.
unplug the wires and unscrew it. hm...I wish I can tell you more details..but I'm just bad at explanining stuff...
 
So I checked the service record from the last time this problem occured, and I realize that Mazda DID replace all 4 plugs, the coils, and wiring (at least thats what it shows). So I'm really thinking it's not just the plugs, or the wiring. It doesn't sound like anyone has had a problem with dead plugs on this car. I feel like I should go back and talk to Mazda again.
 
misfire

Hey fellow P5ers (and other car owners),

I'm having an issue with my P5 that's cropped up twice so far. My engine starts misfiring a cylinder, I take it to Mazda (Roger Beasly North in Austin), and they end up telling me I have a defective spark plug which Mazda replaces and sends me on my way. This first happened last July, and it was cylinder 3, this time (happened yesterday) it was cylinder 4. Actually, this time the service rep said the insulation on my plug had cracked.

Now the car has always run well, except for the 2 misfires and 2 times when it randomly stalled. I've had it since January 04, and I've put 21000 miles on it so far. I tried to get Mazda to do more than just replace the spark plug because I am sure there is a bigger underlying problem. They did replace the ignition coil saying it might have been overworking the plug, but I am sure they did that last time.

The first time this happened, the service rep said he believed it was a spark plug that was defective from the start, am I hitting a bad batch?

Should I just replace all the plugs myself?

I'm curious if anyone else has had similar problems? and how did you fix it?

or does anyone have some idea about what might be going on?

I feel like this is just going to happen again.

I appreciate any help you can give me.

I'm having the same issues. However mine is just with cylinder #2
 
Step 1: Go to advance auto, tell partsjockey you need the NGK V-Powers for a Protege 5 (<$10 for all 4).
Step 2: Get the $0.50 thing of antisieze and a spark plug gapper (also $1) right by the register.
Step 3: Ensure beer is cool in fridge for later use.
Step 4: 10 mm socket: take out the 4 10 mm bolts holding the 2 coils in
Step 5: carefully pull the plug wires off of their cylinders (noting what you pulled off of where), then the coils. I just lay everything in the way I pulled it off on the strut bar so it's easier to put back together.
Step 6: I believe it's a 5/8" socket. If you have a plug socket it'd be easier as it pulls the socket up for you. A regular, deep well 5/8 will work too, you'll probably need a magnet or needle nose pliers to get the socket out. A 6 - 10" extension does wonders here.
Step 7: Make sure the gaps are right (you can get a gauge for that for less than a dolla, also @ advance / any FLAPS.
Step 8: Apply anti-sieze, then get all 4 plugs hand tight into their holes w/o using a rachet.
Step 9: get the plugs 'pinky tight' in their holes. Essentially, pull the rachet w/ your pinky. If it can't go any further, you're good.
Step 10: drink beer.





This is easily one of the cheapest, easiest preventative maintenance things you can do on a protege. It's easier than changing your oil. No reason it shouldn't be done every 15 to 20k miles :)
 
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