I got 01 E320, that just went over 130K. I was wondering If

1) should I change spark plugs
2) should I change spark plug wires?
3) should I change both of them?
4) should I replace something else (like air filter, fuel filter, etc...)

to make my car run and breath better

I looked around, and it looks like people are saying not to change them. I don't think they were ever changed, or they might, I am not sure, as I bought this car a year ago when it had 100K. So I'm looking for any advise.

 

Change spark plugs and O2 sensors - both are due at 100K. Change air filter. Change ATF and fluid filter (due initially at 60K), replace connector while there to avoid leaks into the control unit. You may be able to get some maintenance history from the dealer.

 

I called this Mercedes Indy shop, and they said they wouldn't recommend changing transmission fluid. He said it might make the car worse, and not better. Not sure why he said that.

 

transmission has no issues change the fluid and filter. Diy on www.benzworld.org w210 diy section.
You can't save a bad transmission but if yours is good changing the fluid and filter won't harm it and will prevent it from going bad.
Mercedes even issued a tsb for the same transmission in the w211 models to change the fluid and filter at 39k miles and you as well as most of our w210's are well past that.
Lifetime fluid was a joke....change it and find a new indie mb shop that knows of what they speak.
Change plugs no need to change wires,use the special boot tool to remove the wires from the plugs or you will damage the wires and then you will need to replace them
DIY plug change also on benzworld.org
Use single electrode platinum plugs bosch 7422,ngk 7090 and don't use anti-seize.
Probably time to flush the brakes and the coolant zerex GO5 50/50 mix.
Inspect belt and hoses.

 

wow, that was a lot of useful information. Thank you ohlord. I will then change my transmission fluid/filter, and spark plugs. Should I change air filter?

 

Air filters should probably be changed every 10,000 or sooner if they look filthy.

 

i got a used k&n w/ recharge kit i'm willing to sell. I'm not sure if it would fit your airbox, but olord my know better