I have owened my Rainer for almost 6 years and it has 92,000 miles on it. It is not as peppy as it use to be. The Maint. manual sais to check the spark plugs and wiring harness at 100,000 miles. The local dealer recommends a tune up ( replace the spark plugs and wireng harness). Do you agree?
Should I get a tune up? on 2004 Buick Rainier
I have seen these engines go well over 100k miles on the original plugs and wires. That being said, every vehicle is different and if no other causes are found for the slightly degraded performance of your 2004 Buick Rainer changing the spark plugs, wires, and filters would be a good place to start. Your Rainer may or may not have an inline fuel filter - 2004 was a transition year. If it has and inline filter, be sure to replace it as part of the service.