i have a 2007 honda fit with 120,000 miles. i have noticed a jerking when stopped and idling (in D) and when in 5th gear. any ideas what it might be?
there does not seem to be any changes in RPMs when this is happening
What frequency is this “jerking”? How regular is it? Maybe running on 3 cylinders.
Not constant. might go for 10 or 15 minutes between episodes. last night, seemed like it wanted to stall when accelerating from a light
Sounds like you are trying to describe an engine miss… The thing about engine misfires are that they do not always throw codes that you can use to troubleshoot. This happens when all the coils are doing their job and working fine…no codes get thrown when a wire goes bad or a spark plug etc… something that the computer is unable to monitor.
Blackbird
I own a D model 08 and and E model 09 Fit. After reading similar problems for the last 5 years I would suggest you look at your coil packs. Their failures are similar to what you describe and occur above 100k. They are rarely complete failures but seem to burden the owner with these issues from time to time. The complete after-market coil packs are less than $100 and can be installed easily. Sometimes these misses appear on the error codes and sometimes they do not. I recommend you read up on this issue by going to fitfreak.net and searching for coil packs, etc.
The ignition system seems like the place to start.
Mitch F nailed it. Coil Packs! Classic symptom I experienced on my '08 Fit last year. The Coil Packs on the '07 and’08’s somehow allow for condensation to corrode them internally. If you look at the new Coil Packs, they have a weep hole. Coil Packs boost your 12v to over 20Kv to provide the voltage to jump the gap on the spark plugs. In the old days, a single coil this this with a distributor cap. Now each cylinder has its own coil. I went ahead and changed out all 4, finding that 1 was bad. I gave a good one to a buddy experiencing the same miss, and that fixed his problem, and kept the other 2 as spares. They’re very easy to swap out with a ratchet and you’ll be getting better gas mileage with the misfire gone.
This commonly called a “COP” for coil-on-plug. (A coil pack is something else.):
http://www.1aauto.com/content/articles/ignition-coil-packs.html
A bad throttle position sensor can produce similar symptoms.
Offhand, it sounds like an engine miss to me also. I might ask when, if ever, the spark plugs were last changed.
I think we are all in agreement. Your engine should have COP ignition system. Coil over plug will throw a CEL when one of the coils is not firing…however they will NOT throw a code when your spark plugs are failing and or the spark plug wells are full of oil or water and the coil is going to ground prior to getting to the spark plug.
I would change the spark plugs with what came out of there…Probably NGK plugs… and be sure there is no liquid of any sort down in the plug well.
Let us know how it goes
Blackbird
mis fire that might be more pronounced by bad engine mounts.