If there's a thread for this I apologize, I didn't see it.

I have a 2005 TL, ~90k miles. Since she's getting up there in age and mileage, I just want to make sure that it's performing as well as possible, short of any major mods. The goal is to get it back as close as possible to showroom condition, i.e. keeping it stock.

So what are some things I can check/tweak/tune/replace to make sure it's running at peak performance? I'm just looking for some cheap and easy maintenance, not replacing the exhaust system and adding a turbo.

 

have you been keeping up with maintenance?
ie: oil changes, fluid changes, spark plugs changes, timing belt changes, etc?

if anything is broken fix it.

those two pieces of advice will keep your car running in tip top shape for years to come

 

- Engine oil / oil filters
- rotate tires
- inspect brake pads
- cabin filter replacement (15,000 mi)
- inspect drive belt
- tranny fluid
- check spark plugs
- check timing belt, water pump
- check valve clearance
- replace engine coolant
-

There's owner's manual for service recommendations as well if you need to check on what mileages each needs done.

 

Replace the PCV valve, especially if you've been running conventional oil. The reason for this is that it gets oily and can get stuck open or closed: both are bad. It's cheap and will only take you about 5 minutes.

 

to be honest your car is probably running just fine with only 90k miles. i highly doubt you are losing any noticeable performance from any maintenance items. spark plugs are due soon, that will probably make the biggest difference, but even that most likely wont be noticeable

 

90k miles isn't very much, but id be focused mostly on maintenance items like others have said. You can do the timing belt really any time now, also spend some time with the transmission, if you have an AT something you could look into is replacing the 3rd and 4th gear pressure sensors, and chainging the fluid. You could also spend a Saturday detailing it. Clay bar, wax. Clean all the nooks and crannys in the interior, take the front seats out shampoo the carpet, etc.

 

investing in a good set of tires is always good imo.

 

Yup, maintain (appropriate and at proper mileage) and drive. No need to overdo it. These cars with decent maintenance will last 200-300K easily. I'm at 91,000 miles myself. Things like spark plug changes are for maintenance and will not change performance.

 

I am at 107K and thinking about new suspension.Oops, just reread OP's title. Not too sure if suspension upgrade is "simple"

 

I'm wondering if all the help classifies as "performance" tweaks - or regular maintenance.

I have the same questions the OP has, and I regularly maintain my '06 that has about 121K miles. Within the month I'm going to replace the dashboard that has 2 nasty cracks from the passenger-side airbag. But more on topic, I think, which would be better - adding a K&N air filter or an air intake pipe with K&N filter?

 

^the title was for performance; however the meat of his original post is about maintaining.

as long as you replace the broken items, if they are broken, you'll be golden for a long time to come.

-Always use premium fuel. as it has cleaners and detergents in them, as well as being less prone to detonation.
-change oil and oil filter regularly. Preferably when the MID calls for it.