2005 civic si rough idle, poor fuel economy after timimg belt change
 

I brought my perfectly running car to the honda dealer for the timing belt change out as suggested by the service manual for the 6 year mark. Upon getting it back, it has a rough idle and the fuel milage is really poor. I used to get 650 km per tank, now getting 450 km. I've had it back to check timing marks and they tell me there is nothing wrong with it. I'm really mad about their sloppy work and I have been hung out to dry on this one. I've been trying to repair this on my own and am looking for suggestions. Here's what I've done.....New OEM plugs, gaped to spec, new air filter, shecked for vacuum hoses or electrical disconnected. I'm on my second tank of 91 octane, ethonal free fuel with a fuel injector cleaner put through the system. All this and no change, still shakes the car at an idle when at operating temperature and still poor gas milage. ANY SUGGESTIONS WILL HELP?

Re: 2005 civic si rough idle, poor fuel economy after timimg belt change
 

This is why I hate taking my car to places...See if the shop who did the work on your car will let you get a second opinion and they pay for it...If they are so confident about their work, this should be no problem IMO.


Stop doing your own work, anything you do can void that warranty with the shop.

Re: 2005 civic si rough idle, poor fuel economy after timimg belt change
 

If the problem is the timing I'll be absolutely shocked.

Re: 2005 civic si rough idle, poor fuel economy after timimg belt change
 

is your Check Engine Light on? Even if it's not, go to an auto store that let's you use the scanner for free and check, just in case your MIL is out or disconnected...

Oil level?
Radiator Fluid level?