***I SEARCHED*** ;), please help. Misfire issue in cylinder two!

samsu402 · 10-19-2008, 11:52 PM

I just bought a 2000 Mustang GT and I am running into one problem that is growing on me. The service lights comes on and flashes for: p0302. In other words, cylinder two is misfiring.

The first thing I did was change the spark plugs. When I took out the plugs, one of the cylinders had a wet plug that smelled like gas. I bought NGK plugs (did not gap them, since I assumed they were pre gapped), but after I put them in and started up the car, the problem was still there. It has a sluggish idle but does not mis-fire at wide open throttle.

When Im driving, and the light flashes, you can feel some hesistation. My guess is to change the coils and work from there. I have done my research through this site, but alot of the posts end with no success. If anyone has had this problem, can you please post what fixed it.

For now, I disconnected the injector harness for that one cylinder so it stops dumping fuel in it.

ps. how do you know which cylinder is which (standing in front of the motor). Is it:

4 8
3 7
2 6
1 5

or

7 8
5 6
3 4
1 2

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samsu402 · 10-19-2008, 11:54 PM

are coils a common problem on these cars?

myslow2002gt · 10-19-2008, 11:56 PM

Check the coil boot, make sure it's not cracked. If it's not, try swapping coils with another cylinder and see if hte misfire follows with it.

Modular_Madness96 · 10-20-2008, 12:01 AM

I had a similar issue on my 96.Went through changed plugs,wires,coils,# 7 injector,IAC,TPS,EVR,DPFE,and last the EGR ended up being the issue.Oddly enough the EGR checked out and held vacuum and was clean.Still i swapped it and it fixed it.

My issue was on number 7 not 2 but its worth a look.

cliffyk · 10-20-2008, 12:22 AM

Here is what the factory manual says about P0302, and as others have suggested check, or just replace for good measure, the boot on the COP. You can get replacements at your FLAPS, or online here for $3 a pop.

Spark plugs are not pre-gapped , this is from NGK's website (click here):

Quote:

3. Gapping
Since the gap size has a direct affect on the spark plug's tip temperature
and on the voltage necessary to ionize (light) the air/fuel mixture, careful attention is required. While it is a popular misconception that plugs are pre-gapped from the factory, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for [emphasis added]. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings (to ensure ignitability
in these denser air/fuel mixtures). As a rule, the more power you are making, the smaller the gap you will need.

In the last, the #1 cylinder is at the passenger's side front, #5 at the driver's front. There's a diagram of the cylinder numbering on my O2 sensor page.

samsu402 · 10-20-2008, 01:18 AM

Cliff, thank you. That was very informative. I made this post to find out what commonly goes on modular fords when it comes to misfires. What have people changed that fixed the problem?

aynjell · 10-20-2008, 01:24 AM

Quote:

Originally Posted by cliffyk

Here is what the factory manual says about P0302, and as others have suggested check, or just replace for good measure, the boot on the COP. You can get replacements at your FLAPS, or online here for $3 a pop.

Spark plugs are not pre-gapped , this is from NGK's website (click here):

In the last, the #1 cylinder is at the passenger's side front, #5 at the driver's front. There's a diagram of the cylinder numbering on my O2 sensor page.

I've only read one thing from your website and I hate you: only because I couldn't find you on google when I needed you. =D