100k Tune-Up for 98 GT - All Stock

Hi, couple of months back my GT went from baby to teen, 100k on the odo. Since then, I have put like 500 miles on it because of work travel and rental car provided. Back then I got a suggestion to stick to AC Delco sparks. But here's my question: Since I would like to add some flavor to this all stock car, which spark plugs shall I go for and cables since is 100% stock no mods engine? Dont want to cause any damage to it.

Also, I plan to replace Gas filter, Clean the EGR, new PCV valve, do a Tranny pan drop and filter xchange, cooling fluid replacement, air filter and oil filter, of course.

Thanks for all suggestions on this great forum!

AC plugs will do just fine just make sure they are platinum. As far as plug wires any set that meets OEM specs is acceptable. AC Delco wires are just fine too. The other items you indicate that you will be replacing will help with the longevity of the car. I would consider a professional fuel injector cleaning just to make sure the fuel injectors are clean too. Other than that you should be good to go.

You might want to balance and rotate tires if you haven't done it recently and replacing the brake fluid is also a good idea if you have never done it. The fluid will deteriorate over time and can cause issues. Inspect all brake lines as well.

Some other suggestions are to replace the hoses and the belt just so you don't break down especially if they have never been changed.

Good luck!

My last set of plugs and wires had about 180,000 miles on them. After changing them out, I've seen no increase in gas mileage or performance. I'd stick with AC Delco plugs and wires though. I'd vote for the hose and belt changes too. I keep the old belt in the trunk for emergencies with a well equiped toolbox. A piece of 12-14" 3/4" pipe for a cheater handle for the ratchet comes in handy along with the outlaw 16mm socket for the springloaded pulley.

Even if you are stock there is nothing wrong with using other brand spark plugs like Autolite Copper Core, Single or Double Platinums or the NGK equivalents like the TR55IX Iridium so you do not have to stick with AC Delco. The recommended AC Delco plugs since the OE Delco double platinums are no longer available is the 41-101 Iridium which are made for GM by NGK. If stock just make sure plug gap is at .060".

Another suggestion is to be sure to clean the throttle body including the MAF sensor and Idle Air Controller (IAC). A lot of carbon builds up inside the throttle body after several years and accumulated mileage.

Another common mistake when changing the PCV is to forget to take the small black o-ring off the old PCV valve and transfer it to the new one. Failure to do so will result in a vacuum leak which can cause false trouble codes and a whistle/squealing noise.

Awesome!! Thank you very much to all of you, I'll write all this down and do all I can by myself and leave the complicated stuff to a trusted mechanic I have here in northern Virginia.

Thanks again!!