mileage and power drop

[screamin86]

well my yukon is up to about 94k now original plugs/wires (to my knowledge) change oil every 3000miles with 5w30 valvoline and k&n oil filter. my mods in sig but lately like the last month or two ive noticed it being much more sluggish even on the cool nights and my mileage has droped considerably to 12 with mixed driving where i was getting 15-16. ive got a new fuel filter i need to put on but i need the tool to do it. woul checking out my cats to see if they are getting clogged help? ive been debating on gutting them anyway. id rather wait for longtubes and ory but we are in the process of closing on a house so it will be awhile before i have extra money for mods so any more free/cheap mods repairs are the way to go lol. it feels like it needs to downshift more to get around than it used to and like i said just feels like its struggling.

[Maui4x4]

94k on those plugs isnt helping much lol... change those suckers out and clean your MAF. Plugs do make a world of a difference at that mileage, after your done with them then check your cats if you dont see a improvement.

[oleshifty]

Put your hands about 3 inches from exhaust exit. If it burns you, cats are bad. If not (and you're not constantly sweating while driving) they are probably ok.


My mom's tahoe has 145k on original plugs and it's still fine, I'm not sure if that's the problem. Possible. I'm a pretty firm believer in changing delco plugs/wires every 100k with more delco plugs/wires. Hasn't failed me yet. (They would throw a code if they were THAT bad). Changing my oxygen sensors helped mileage quite a bit and they never thru a code for 'being bad'.

Fuel filter wouldn't hurt (you should be able to use a pair of needle nose pliers...most chevys either thread in or have the pinch clip..i've only seen fords that need a special 'tool') But I don't think that's the problem either. If fuel was THAT restricted, it'd throw a code.

[2003silveradobell]

i also had my plugs and wires in untill about the same 145,000.

[bangbangskeetskeet]

Put your hands about 3 inches from exhaust exit. If it burns you, cats are bad. If not (and you're not constantly sweating while driving) they are probably ok.


My mom's tahoe has 145k on original plugs and it's still fine, I'm not sure if that's the problem. Possible. I'm a pretty firm believer in changing delco plugs/wires every 100k with more delco plugs/wires. Hasn't failed me yet. (They would throw a code if they were THAT bad). Changing my oxygen sensors helped mileage quite a bit and they never thru a code for 'being bad'.

Fuel filter wouldn't hurt (you should be able to use a pair of needle nose pliers...most chevys either thread in or have the pinch clip..i've only seen fords that need a special 'tool') But I don't think that's the problem either. If fuel was THAT restricted, it'd throw a code.

You would be surprised how much the filter can restrict flow without throwing a code...I replaced mine after around 145k and I gained about 2-3mpg.

[oleshifty]

You would be surprised how much the filter can restrict flow without throwing a code...I replaced mine after around 145k and I gained about 2-3mpg.

I changed mine right around 110k... Went to do it last month (at 160k, found one on the shelf) and my lines are SHOT. I will have to replace the line on both sides of the filter, its completely rusted to the filter. Not in the mood, it's good enough lol.

[screamin86]

Well what plugs do you guys recomend for plugs? Like I said I have the filter I just need to put it on. I know one end is threaded the other has a clip fitting.

[screamin86]

i changed the fuel filter and it was the ORIGINAL delco one lol black/brown gas came out of it i also found a gas station local that has non ethenol gas i filled up there and tomarrow im going to pull my air filter off and clean it real good. i put my hand at the exhaust exit and it was hotter than normal but not at the burning my hand point like some ive delt with but ive noticed and coworkers have noticed a odd smell from the exhaust more lately. after awhile of idling the other night i was standing next to it and could hear a distinct miss in the idle but i dont get it anywhere else in the rpm range so im going to try to get some plugs for it this week just need to find a good set.