I suffered through what many on this forum have described as the "jerky fit" syndrome. In an attempt to discover the cause I found this site which was extremely helpful. My 2007 Fit for over a year has been misfiring intermittently. I went from 38 MPG to 25 MPG and at times was convinced the car would stall at a high rate of speed. It did in fact stall a few times stopped while at idle. I would get a check engine light with a p2646 code and a P0420 code. I would reset the codes and they would immediately come back.

After searching this site for similar issues I concluded that it was one or more coil packs. The problem was trying to figure out which one. Since it did not miss all the time I never got a code for which cylinder was missing. Spending big bucks having them diagnosed was not an option. I did try disconnecting each one while the engine was running but each disconnected pack produced the exact same change in the engine making it impossible to distinguish which one it was. So it became apparent that I had a reduced performance coil pack or packs that where not totally dead.

I then came upon a thread, I appologize because I do not know where I read it from although it was from this site, that related similar problems and suggested regapping the spark plugs. Seemed like a cheap solution so I figured that I would give it a try.

I bought new plugs and regapped them to .035. Started it back up and it purred like a kitten. All symptoms are now gone. 12 bucks and a half hour was well worth it. Thanks to whoever discovered this and if you have similar problems try regapping the plugs.

 

so you made the gap smaller... from .055 to .035?

 

I thought somebody had tried that, but it came back after a month or so? Once they replaced the coil packs, it went away permanently.

 

From the way that your engine responded to the smaller plug gap it sounds like the dwell time for your coils to recharge isn't long enough for them to get fully charged ... I have to run a tight gap due to having a supercharger.

 

Yes. The ones that I bought at NAPA came gapped at .045. So I regapped them to .035. I am sure that the coils will eventually fail, but at least in the mean time it seems to have been a cheap fix. I will let you know if I have any more issues.

 

I read a recent post but can't find it now... A guy was having the same situation and someone at a dealership(I think) told him that if his valves were in need of adjustment that would cause the problem and mess up the coils at times.... I could be that way but I am not sure... I am considering a valve adjustment in the near future just to be safe ...If your coils were over charging because of too much dwell tightening the gap on your plugs wouldn't have made a difference.

 

hi Donor, Thanks for your tip, any issues later on so far ? I will follow your way but want to make sure it works. Please update if possbile !

Cheers

 

DWow, 3 years later, and somebody finally tries my cheap fix!

4/21/2009 plugs gapped to 0.035"

Most recent post about hesitation fix...

6/17/2012 plugs gapped at 0.035" fixed Konig Feather's problem

Denso IK22s set at 0.032"

12/27/2011 regap does the job once again

Donor, thanks for acknowledging that this does work for some Fits!

 

Definitely works. I have an 07 Fit Sport I got at the beginning of Sept. It was missing here and there. I finally got time after 2weeks to pull the coil packs and plugs, put electric grease on everything and re gap to 040. Problem solved. All plugs but one looked the same. #2 had orangey residue. Thinking that's the one that was misfiring. With the grease & regal they're all going good now and MPG has gone up.

Meanwhile I'll use the time this buys to get new coil packs & plugs.

Donor, thanks for acknowledging that this does work for some Fits![/QUOTE]

 

Good to know! Subscribed and filed in DIY folder!

 

Hi all

They were going to charge me R8000 to fit a whole pack of new coils. This is the equivalent of $500. I am glad there may be other solutions to this problem. Thank you for the discussion, and for being proactive about the care of the car.

PS in South Africa, we call the Honda Fit the Honda Jazz

 

A narrow gap may give too small and weak a spark to effectively ignite the fuel-air mixture, but the plug will almost always fire on each cycle (so your cat will be F...d up, but most people on this forum too tight on the budget to invest in new plugs). A gap that is too wide might prevent a spark from firing at all or may misfire at high speeds, but will usually have a spark that is strong for a clean burn.
As a rule, a properly gapped spark plug will burn hot without being too wide at high rpm to cause a misfire. Ironically, the car manufacturer's recommended spark plug gap is not optimal! The recommended spark plug gap is designed to be adequate for cold starting and smooth driving on a car that is in need of an engine tune up. If you drive your car normally and tune the engine regularly, you can increase the spark plug gap by about 0.010" for better performance and better fuel economy. However, if you drive at full throttle most of the time, you should reduce the gap by about 0.010" for better performance. sparkplugs - How much does spark plug gap affect fuel efficiency? - Motor Vehicle Maintenance & Repair Stack Exchange
How about downgrading to point type ignition

 

Glory Be! I just found a couple condensers from our 1970 Ford Cortina!

 

The point is if some motorists are so cheap to invest in oem recommended plugs instead of messing up with gap (and causing more problems down the road), why don't they buy something more affordable to maintain (perhaps 4 cylinder car from late sixties with no emission equipment). I often see people complaining about car related expenses (they are driving former top end clunkers such as 89 Lexus, 95 Mazda 929 or 95 Nissan 300 ZX)

 

Did a lot of research here when my 2007 Fit started stuttering a few months ago, then last week the check engine light came on after a serious hiccup, then cleared after a can of Sea Foam put in fuel, then more stuttering, then a tick, tick, tick noise, then the engine light again two days ago.

Just changed the spark plugs; #4 was loose and the coil pack was dark/dirty. Took a test drive - no ticks, no stuttering, all seems good!

Will see how it goes over the next few weeks. I drive 400 highway miles a week for my commute to work.

 

I have a 2007 Fit with 150,000 miles.

I've had these "jerky" moments in the car a lot this past year, and they only happen in damp/cold mornings.The serpentine belt in my car was way overdue.My guess is that belt slip caused the alternator to run inefficiently and messed around with the voltage to the spark plugs.

Don't take my word for it but I recently changed my serpentine belt and it has all but completely been nothing but smooth acceleration.

 

I have seen multiple threads over the years on coil pack failures on Honda Fits. We have or have had 3 Fits with a cumulative mileage of about 270,000 miles and have never needed to change a plug or coil pack. So I have just read about the problem and not commented because we have never experienced the problem.

Way back is 1975 GM first came out with their high energy ignition. It is effectively the same thing as we are using today only they used one coil and a distributor to send the spark to the appropriate cylinder.

GM started having random coil and occasion control module failures with the HEI ignition and never really fully fixed the problem. The original spark plugs were gaped at .080". GM quietly reduce the spec to .060 and that helped some. They never did much else. They just sold replacement parts after that. A GMm dealer in Ontario decided to do some dyno testing. He found that he could run the plugs as low as .038" and not affect the engine operation and mileage.

Today there are still al lot of those engines around. I own a 1976 GMC motorhome with one of those engines. There were 12,931 of them made and there are still over 8,000 of them on the road in countries all over the world.

Anyhow this GM dealership was a big GMC dealer and sold a lot of GMC motorhomes. He still drives one to this day. He started suggesting that the plug gap be reduced to .040". What we in the GMC community have found is following his recommendation at .040" is coil failures are almost non-existent. I set mine to .045" about 15 years ago with platinum plugs and have never looked at them again. Most of the GMC community has done the same.

Based on the above, I am wondering if it would not be worth the time to reduce the spark plug gap to something in the .040" to .050" and see what happens to coil pack failures on a Fit.

 

Misfire when wet is generally related to micro cracks in the coil boot so the spark jumps to the spark plug well wall; this takes place if condensation occurs inside of the spark plug well as engine cools down during wet weather. Something similar happened on 93 Mazda Protege and Ford Escort; the solution was to add a vent hole to the spark plug well grommet (on the wire); A TSB even suggested making a hole in the grommet, if replacement wires not readily available. It looks like Honda went this route for the replacement coils.

 

If you read through the (voluminous) discussions here, about mis-fires and coil packs, you will see that some have advocated setting spark plug gap at around .035".

I've never done that myself. Always run the spec on the hood sticker...

 

hie guys!
Am not sure if i am posting on the the right forum but either way i need your help.
i have a Honda fit 2002 and it randomly switches off at any given time whilst the car is moving. it has an engine check light on and the diagnostic machine indicated to an ignition signal failure. sometimes the car misbehaves sometimes it doesnt. when it switches off whilst i am driving i have to remove the battery terminal for me to start it again and move, other than that it doesnt move. i have changed plugs i have changed fuel pump now am changing the crank position sensor. somehow am afraid it wont work. Does anyone have any idea on what could really be the problem with this vehicle?