Focus rough idle

I have a 2000 Ford Focus that vibrates more at idle. The previous owner replaced the top passenger side motor mount when I bought it in Nov. I just replaced the bottom and then the other top drivers side mount two days later. 75% improvement but I wonder if there is some thing in the engine like an adjustment of some kind. I have only had it a couple months so I don’t know when the last time it had a tune up. I can replace the spark plugs my self but would need a computer diagnosis to determine if there is something else that needs some adjustment of replacement.

If you just got the car then you should just do the basic maintenance items. Normal ones would be spark plugs & wires, air & fuel filters.

You never said how many miles are on it, but no matter how many I’d add cleaning the MAF sensor, throttle body, and idle air control (IAC) valve.

The timing belt is not relevant here, but if you don’t have any records telling you exactly when the belt was changed then assume it never was - and get it done now.

Then see where things stand. There is no “adjustment.” Its a little car known for not feeling the smoothest at idle and yours is probably not running quite right. So start with the basics.

Stew dropped this in my inbox so I figured I’d help him out & add it to the thread:

"It has 139K miles on it. I was told the timing belt is new also when it was being prepped for sale. Could this vibration be normal for this engine? I paid $284 for the top passenger and bottom motor mount replacement on my previous car, a 2001 Ford Escort. It also had a similar vibration problem. The new motor mounts did not resolve the vibration either. The shop told me to bring it back and they would continue working on it. Unfortunately some one ran into me before I could bring it back. I did not want to pay them another $284 so I decided to tackle it myself. I am glad I did because both mount were extremely easy to replace. I will pursue your suggestion and let you know. Thank you and how much do I owe you? "

Stew, you owe me your undying gratitude! Just help out everyone here by updating as you pursue the issue so that people know what comes of it.