100K tune Up sugestions

[weezzle]

My '02 LT i6 ihas almost 100K on it and feels like it needs a tune up. I have religously changed the oil every 3K. It feels very sluggish on take off for some reason and just feels like it does not have much tourque and I am only getting 17MPG. Only current mod is a drop in K&N.

I was basically going to start with plugs and maybe plug wires?

Any other suggestions for the 100K mark to get back that lost HP?

[markhart1]

Sounds like cleaning the throttle body is a good idea. Your I-6 does not have plug wires

[rbarrios]

17MPG on highway or cmbined? thats good mileage if its in city....
at 100K, youre due for new spark plugs. Simply get the AC Delco Iridiums (they used to be Platinums).
dont even bother with aftermarket stuff like splitfire etc- users here report bad results with stuff other than OEM. AC DELCO is the way to go for plugs
also maybe your cat is getting plugged- thus the lack of power

[ylab]

Just like rbarrios said, you most likely need plugs at this point. If that doesn't fix it, your CAT may be clogging up......VERY common on the '02 & '03 model years. They went to a larger capacity unit in '04 and added a small electric AIR pump at the same time.

[weezzle]

Are the AC Delco plugs only available throug the dealer? Autozone carries a Denso irridium. Wonder if that is the same thing?

[weezzle]

Never mind last post. Just verified with dealer. I am going to swing by and pick up the AC Delcos 2nite and I'll let you know if I notice a difference.


17MPG is combnined city/highway. I guess not too bad, but I've seen post of people getting 20+. never here, guess I am too heavy footed.

Thanks.

[Super 88]

Originally Posted by weezzle

17MPG is combnined city/highway. I guess not too bad, but I've seen post of people getting 20+. never here, guess I am too heavy footed.

Thanks.

I'd take most of those posts and claims with a grain of salt! Case in point, someone recently claimed to get over 34 MPG!

http://forums.trailvoy.com/showpost....6&postcount=27

[rbarrios]

since you have the 02- and the 18.6 or so tank- and youre getting about 17 MPG- you should be seing the halfway mark around 165 miles, and the low fuel light around 280.
Im currentlly getting about 300 miles on a tank- and refuel with 16.7 gallons.
I too am doing city/highway and getting about 18 MPG on consistant basis- everyweek. I have gas/mileage written down for my TB since I bought the SUV... So I know Im getting 18 MPG regularly.
The times Ive done long non stop trips (no luggage) and cruise with 60-65, Ive achived a best of about 24 MPG.....
like mentioned- there was a post of 34 MPG... but I find that very hard to believe- there must be a miscalculation somewhere.

When you change your plugs- do it with a COLD engine- like after its sat overnight.

[weezzle]

At 34 MPG they must be pushing it.

thanks for the advise on the spark plugs. I'll did not get a chance to do them last night anyway, but I did pick up the plugs.

I was talking to the service dude at the local Chevy dealer. He recommended a Fuel Filter change too. Is that something that is easy?

They did offer a 100K tuneup package for $380.00. Not too bad really. I thought I would knock out what I can and then le tthem do the other stuff like tranny, differentals, brake fluid flush, coolant, and whatever else.

[Bearcat]

Power steering fluid flush.
Tranny filterand flush.
Differential front and rear fluid chane (every 40K)
Transfer case fluid change (every 40K)
Check the serpentine belt
Check coolant capacity.
Fuel filter.
That will keep you busy most of Saturday.