Why does my 2008 Honda Fit intermittently shake when AC is on, in drive, and foot on brake?

honda
fit

#1

Why does my 2008 Honda Fit intermittently shake when AC is on, in drive, and foot on brake?
The shake is every 2 to 10 seconds, darn short each time, and hardly strong. (If it happens when I’m driving then it would be hard to notice).
It definitely does not happen when in park or the AC is off.

Three weeks ago I got a rebuilt transmission. This issue started for the first time 3 days ago when the weather turned very hot for the first time in a while, although I have used the AC from time to time beforehand.

Is it safe to drive over the weekend?


#2

When the AC clutch engages, it puts add’l load on the engine. Putting the transmission in Park removes some engine load. If something is slightly amiss with the engine or its tuning, a symptom like this will likely show up more under load. Since it happened after a transmission rebuild, it could be associated with that also. Ask your mechanic for a read-out of any stored diagnostic trouble codes from either the engine or transmission. Besides bringing all the routine engine maintenance up to date, that’s probably where to start.


#3

Very helpful, thanks.
Can I drive it a little over the weekend before my mechanic opens on Monday?


#4

If you have safety concerns, best to ask a pro to have a look.


#5

It is safe. It could be needing a tune up or the IAC could be dirty. Cleaning the IAC and replacing the plugs could very well take care of it.


#6

My Honda Fit Sport (2008, 90k miles) just started that same shaking yesterday after I got an oil change by the Honda dealer ship. Brought it back this morning and they say it’s a bad coil.
My car had no issues before the oil change.
How can that go bad out of the blue after an oil change?
Maybe it can - but I really would like to know how/why. Ideas?


#7

Out of millions of oil changes, a few will certainly be coincident with many other failures. You’re the (un)lucky one of the moment. If you’re at all handy with tools, buy a coil and replace it yourself. If the computer codes don’t tell you which one, just start at one end and try each one until fixed (or not).