Hey guys I just bought an 04 Acura TSX with 71 thousand miles on it. I was wondering what preventative maintenance I should do because I fell in love with the car and would like to keep it for a long time.
Congrats, I like my 04 so much that I pay for paint and body work to keep it looking nice over the years.
Get a hold of the factory mx list. Anything that you don't have documentation on, better just do it to be safe.
Given the years on the car, I'd do all fluids (unless you have docs that they've been done recently). So coolant, tranny, brake, and clutch (assuming manual?). Also power steering fluid, the PS rack will fail if you don't. Also filters (don't forget the cabin air filter, those get naaaaasty if ignored for ten or fifteen years lol).
Conventional wisdom on all Hondas is to use stock fluids, this is important and WILL affect component durability. You can use whatever good oil, full synth highly recommended. I use Mobile-1, with a long-life filter (I use mobile filters) the OCI can easily be 7-10K miles. If in doubt, change the oil and run it to 7K then send an oil sample to Blackstone... they'll tell you what shape your oil is in so you'll know if it's still good. You can adjust from there. My lab results show I could do 15k easily (mostly highway miles in my case). I change it 10K so I can rotate the tires while it's jacked up.
Motor mounts will fail eventually, normally that would be over 100K but age might play a factor too. Shifting will get rough if that happens. A manual tranny should shift like butter on this car.
To avoid breakdowns, I'd probably do the thermostat since those typically fail more on age than mileage.
Also the sparkplugs. They're still under the factory interval but they might tend to corrode from air exposure over that many years, at least inspect them. I use Denso Iridium Twin Tip 4702; stock works fine too.
Coilpacks... they will fail eventually, I think it's more heat and mileage than age but not certain. If you're going on a long road trip I'd probably bring a scantool, spare coilpack and sockets just in case. You can diagnose and replace a bad coilback by the side of the road in about ten minutes.
For upgrades, I'm a stock kind of guy but the brakes are a little soft and the rotors prone to warp and pulse. I installed StopTech nylon/SS brakes hoses, Red Stuff pads, and EBC USR rotors. Much better brake feel and no pulsing. You need to torque all the lugnuts the same, so use a torque wrench ideally, otherwise you can get brake pulsing due to uneven seating of the rotor.