Misfires

[mike]

I have a 2007 fit with 77,000 miles, been to the dealer for every repair or oil change. I had a misfire a back in oct 2009 after about five times to the dealer and $600 now they say it could be my coil packs and another $500.Has anyone had a misfire problem like mine? found answer in another thread.

[manxman]

I have a 2007 fit with 77,000 miles, been to the dealer for every repair or oil change. I had a misfire a back in oct 2009 after about five times to the dealer and $600 now they say it could be my coil packs and another $500.Has anyone had a misfire problem like mine? found answer in another thread.
This is a common problem, at least for the GD3's. Our member macbuddy has had the problem, and solved it himself by reducing the spark plug gap from the factory setting of .047- .052", reduced to .035". Reducing the gap also reduces the amount of electrical power required to make the plug fire with a weakened coil pack. www.fitfreak.net has several virtually endless threads with hundreds of posts regarding the problem. Watch on Ebay Motors- I have seen several ads for reduced prices on Fit coil packs.

[mike]

Thanks, they look pretty easy to replace maybe just a little tight.

[manxman]

Yes- they are easy to replace on GD3 Fits. Good luck with getting rid of the problem. The dealer quoting you $500. for the replacement of the coil packs sounds like an absolute rip-off.

IIRC, new coil packs cost around $60.00 retail. If you shop carefully at on-line parts stores, you should be able to buy them for less. All you need is a ratchet wrench, a 10mm socket and a 4" socket extension, and you can replace all of the coils yourself in 30 minutes.

[macbuddy]

Hey Mike,
Do me a favor and try regapping your plugs to .032"-.035" before spending ~$500 on a new set of coilpacks...then report back to let me know if "my" fix works for you too.
I've been running mine at .032" for about a year now with no ill effects. I am still able to achieve +39mpg, and still able to run decent times in AutoX events.
If this fix does work for you, take the extra $500 and spend it on new tires, or maybe a suspension upgrade instead!
Cheers,
-macbuddy-

[macbuddy]

Okay, I've been able to delay the need to purchase a new coilpack for just over a year now. My practice of reducing the gap down to .032" has given me just over one extra year of service. For the record, my Fit has been performing well ever since the adjustment.
Well, as of yesterday, my #4 coilpack finally gave out. It was kinda embarrassing when it did. I was charging up a sweeping on-ramp when the CEL lit up. The engine misfired, and immediately lost torque. The speed dropped down to ~40 mph, and I could not accelerate, as the engine would continue to misfire under load. At that rate of speed, I became an instant "traffic hazard."
When I finally pulled off the freeway, the Scangauge2 showed a P0428 code. After looking this up, I learned that I had a "Catalyst Temperature Sensor Circuit High" warning. WTF did that mean? Anyway, I "babied" it the rest of the way home. By the time I got home, another CEL was thrown. This time it showed a P0304 code, "Cylinder 4 Misfire Detected." Okay, now the P0428 code made more sense.
This morning I purchased an OEM coilpack from my local Honda Parts dept for $87 plus tax. After a 10 minute install, I got my Fit back into perfect running condition once again!
The coolest part about this whole episode is that "Mrs. macbuddy" finally got to see that the Scangauge2 is more than just a "mileage calculator." I love my Scangauge!

[manxman]

Hey Mike,

Just a suggestion here. Now you have 3 more coil packs of the same age and mileage as the one that failed. That means that three more "instant traffic hazard" incidents are on their way to screw you up some day, somewhere. Maybe in the path of a semi with bad brakes. In your place, I would look for the best price on-line and buy the three coils so that a disaster could be avoided. If two of the coils fail at the same time, you will define the term "SOL"!

With four new coils, you will have a new ignition system (with new plugs).

[ming]

My fit has misfire problem too. I only replaced the spark plug to fix it instantly. However, after running 3 weeks the stall issue pop up again. I replaced one coil already to test is the stall issue gone or not. Does it any know how to check which coil pack is dead? I check each coil resistance, there are 3 coils show 1800-1820. Only one shows 1850. I think that one goes bad.:confused:

[claymore]

The only thing that the manual suggests is to take the unit off the plug then get another plug and hook it up then put the extra plug to ground and see if it sparks with the engine running. But that would only show if the sparking unit was working not the intermittent problem that occurs on the Fit.

I would buy one more and trying switching it from plug to plug to see if that cures the problem.

You don't say how many miles you have on the car but if it is over 50,000 I would just replace the rest besides the one new one you bought already. Seems that they go out more than one at a time in the cases guys have been reporting.

Is yours a USDM Fit or in a foreign market? All the problems I have see seem to be on the USDM ones the people on some international sites have not reported the same problems.

[macbuddy]

Ming, I don't know if all OBDII readers can detect codes while the car is in motion, but that is how I was able to determine the faulty coil pack. In my case, my Scangauge determined the problem. If you have access to an OBDII reader, try hooking it up, and take it for a spirited drive.
If you don't have access to one, here is what I would try. First, I'd set all the plugs to a 0.051" gap. If your bad coil pack is going to act up, this gap will speed up the process. Next, I would systematically place the new coil pack on different cylinders. I would take the Fit out for a test run on each position. Hopefully, you will eventually find the weak coil pack. This method will work if you only have one weak coil pack.
If you are persistent, you can try decreasing the gap to 0.040", and go through the systematic process again. Perhaps this will expose the weakest coil pack of your set.
I was running 0.032" gaps when my #4 coil pack failed, so I was sure that that one was "fried!" I may still have 1 or more weak units on board, but with the reduced gap, I feel confident running with them at this point (@ 123K miles).

[macbuddy]

Ming, here is a another idea...and probably the first one I would try. This one won't cost anything, as this test would not even require another coil pack.

HERE IS WHAT I WOULD DO...
First I would set all gaps to 0.032" (reduces resistance). Run the Fit and see if I still experience any misfires. If the coil packs are not "fried," the Fit should actually run good again. (Like I have posted before, I reduced the gap on my ailing Fit, and it ran like new again. I drove my Fit nearly a year like that before the "weakest" coil pack finally gave out).

NEXT...
Now, to test for the "weakest" coil pack, I'd set one plug to a 0.051" gap (increases resistance). Systematically test that "0.051 gapped" plug on each cylinder, #1 through #4. Take an intense test drive with that plug in each position. If I experience severe "stuttering" on any particular cylinder, then I would determine that one to be the cylinder that receives a new coil pack.

MY THEORY...
Hopefully this will help expose the "weakest" coil pack. I did not use this test myself, since I have a ScangaugeII. However, if I did not have such a device to determine which cylinder was misfiring, this idea sounds like it should work.

I hope I am right,
-macbuddy-

BTW, If you decide to try this idea, I hope it works for you!

[ming]

Thanks Calymore and Macbuddy. My Fit already run 88K miles. I do not have any tool to check the code. the new Bosch spark plug gap is smaller than the old one but I did not get how smaller it is when I did the replacement. After I replaced #4 coil pack last night, car running good again now. I don't feel and stall or misfire when it is running 65-70 mph. I believe all coil pack are weak now. It is time to replace them when it misfire again.

Do you know what to cause engine tick tick sound like hot water noise when car starts to move from cold engine. It has been happen from 12k miles until now. The noise was disappear after I replaced the spark plug, but now it shows up again even though replace one new coil pack. Thanks for any advice.