Corolla Maintaince advice

My sisters 06/07 (not sure) corolla S has hit 100k. Its sounds rough and has never had a tune up.

What general maintaince should i do? I though it had a timing belt, but i found that the parts stores list a chain. If thats the case, Ima leave it.

So far:
Plugs
Serpentine
Oil/ filter
Trans filter/oil
Valve cover gasket.


Is there any calibrations that need to be reset? IE: timing, TPS...

You're correct, your sis' Corrolla has a timing chain so less maintenance worry there. You also have coil on plug ignition, so no need for distributor maintenance. A check of the timing may help, but since it is computer -controlled, you're better off just checking for any stored codes in the ECM...no user adjustments are possible.

If it is running rough, it may be time for some decarburization by giving the throttle body (TB) insides and intake a shot of cleaner such as Seafoam or Chevron's Techron fuel system cleaner to remove built-up varnish and gum. These also help remove carbon deposits on the valvetrain and pistons, and sludge build-up...use as directed.

Also, get in there and spray the idle air control (IAC) valve face (not electrical body) and the EGR valves. These can cause rough idle if they are sticking.

Finally, if the car is in exceptionally cold weather (like has been the case recently in Fla!), the rough idle it may be due to the engine and transmission mounts being stiff from the cold. Hope this helps!

Also, check the engine air filter, and the cabin air filter (if it has one).

Check the crankcase ventilation system. Usually this is a hose and a PCV valve, which need periodic cleaning and/or replacement.

It probably is time for new oxygen sensors. There should be two, one upstram of the catalytic converter and one downstream. These usually produce a code when they go bad. However, they do not last forever, and it is prudent to replace them periodically.

Finally, check for general suspension and steering wear, particularly for tie-rod ends and ball joints.

Ill add seafoam, PCV valve and air filter to the list.

Codes were just some evap stuff. cleared them and haven't came back.