How to change spark plugs on 1998 Olds Intrigue?

The first thing you will need is a swivel ratchet, an extension, and spark plug socket 5/8.

Look at your engine. Your front plugs are in the order from left to right: 1-3-5.

Behind the block you got plugs: 2-4-6 from left to right.

Since the front plugs are easy to get to, change out plugs 1-3-5. Do them one at a time!!!!! If you are replacing wires too, be very careful not to get them mixed up.

After the front plugs are changed, here comes the hard part. Looking at your engine from the front, you have 2 motor mounts. Loosen the bolts on both mounts. In the left mount, take the bolt out all of the way. Just leave the right mount broken. Have a partner to jump into the car and "bump the motor". That means cranking it up and put it in gear (reverse). This will cause the engine to shift forward. Dont worry: IT WILL NOT FALL!!!! Use a breaker bar to hoist the motor over more by prying on the right mount.

Place car back in park and turn car off. Now the back three plugs (2-4-6) should be exposed greatly.

Have fun, this is not easy. Be sure to use some good plugs that will last a LONG time. Always use AC Delco (those are GM parts thus the best for a GM Car). I used AC Delco Iridium Platnium plugs. They were expensive ($7 a plug). But they fire better and dont need replacing for 100k miles vs the original 30K and 60K plugs.