2008 Fit rough idle when cold
 

2008 Fit, 55K miles. When first started in the morning in cold weather (but doesn't have to be freezing cold), the engine idles very rough. This becomes especially apparent when putting in drive or reverse. There is a vibration associated with the rough idle, almost like it wasn't firing on all cylinders and the car nearly stalls. In warmer weather or after vehicle warms up, problem totally disappears. Dealer says I need to leave overnight so they can see for themselves but before they start taking "guesses", I'm trying to get a heads up.

Sounds potentially like the idle air control valve problem on Civics and Integras I've seen years ago. The valve gets sticky especially in cold weather and effectively chokes the engine of air as it idles trying to warm up. You notice it most when warming up because it runs rich when it's cold and requires more air to compensate. The vibration could be the engine on the verge of stalling because the ecu can't open the valve far enough.

bad coil pack or two?

Valve adjustment
 

if nearing 60 K get them adjusted- your heasitation will be gone.

One more vote for valve adjustment.

I vote valve adjustment or clean the coil packs. Coil packs won't cost you anything but time and some grease to clean if you want to try that first.

I have the same issue
 

did you get the problem fixed? if so, what was it. i also have a 2008 with exact problem as described.

Yes, rough idle was definitely valve adjustment. I couldn't convince the dealer service shop that the valves in the car were not self adjusting so I brought it to an independent shop where he confirmed the outlet valves were just about closed tight. Once adjusted, the problem completely went away. However I also had a problem where the engine would skip and that ended up being the coil packs. I could have done one at a time to find out which one was bad but I just replaced all four at once.

I also had a problem where it sounded like there was a brook gurgling behind my dash. The cooling system had to be purged and there is a service bulletin out for that but I don't recall the number. Again, I had to point out the service bulletin to the dealer to get it fixed for free.

Based on what I've read, there's a very high probability your rough idle is also due to valve adjustment issues.

Wow
 

Thanks for the response. I have mine in the shop now for a water leak that was seriously flooding my back seat. with 91k miles I was hoping for no issues that soon. Crazy enough Honda helping me with the repair cost. Its basically the seam though thought to be the gasket at first.

On the idle, I guess I need to get it to a local mechanic as the dealer doesn't seem to be any more knowledgeable than the local guy.

I guess I should change the packs as well.

Have you had the transmission drain / fill yet? I am considering it.

I would do the ignition coil test to see if you need to change them, start the engine and then start to unplug each coil and see which one will show signs of decreased power. The valve adjustment should be done every 60,000 miles from what I heard. As for who you should take it to, take it someone that you know or just the dealership.

Valve adjustment could be your main source, however it is very easy to clean the MAF out and make sure you don't have any gunk on your filter.


If you are running an oiled filter, some of the oil can get on the sensor and give inaccurate readings.

Spark Plugs, Coil Pack wear and tear, and clogging up cat could also be other sources of the problem.

My main guess would be valve adjustment and MAF.

I had the same problem. Went through a lot to figure it out. It was a loose valve on cylinder 2.

Fit has MAP not MAF:D

Yup- similar issue here with a rough idle when started cold and a valve adjustment solved it completely! 2007 Fit Sport 5MT w/ 88k miles

I have exact same car (2007 with 5MT) except it has 98k miles now on it. I first replaced the spark plugs and coil packs, and that solved some of my problems. Then last Sunday I adjusted the valves and that fixed all other issues.
All intake valves except one, were too loose, and all exhaust valves were tight.

The power is not the same as it was when I got the car in 2010 (with 30k miles on it), but I can tell the difference before and after the adjustments.