Hello I have two cars one is a 2000 Toyota solara l4 se with 100,000 mi and a 2003 Chevy Silverado 1500 4.8l ls with 115,000 mi and I have never changed my plugs during a tune up I have only done oil changes I was wondering if I should do a full tune up I also have a problem with my catalytic converter would doing a full tune up help with this thank you and stay safe.
@chucktobias i have a code for p0420 and sometimes code p0430 i always put on duralube to clean it out
If you look up those codes (they're really the same, just for different engine banks) you'll find there are multiple potential causes that you can troubleshoot.
@chucktobias how do i fix it is thepre anything i can do without replacing the cats thank you and stay safe
There is no "quick fix". As I said look up the codes, potential causes, and troubleshooting information. Here are some to get you started:
https://www.walkerexhaust.com/support/tech-tips/diagnosing-catalytic-converter-p0420-code.html
https://www.carparts.com/blog/p0420-code-catalyst-system-efficiency-below-threshold-bank-1-2-2/
https://www.obd-codes.com/p0420