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17.8 mpg?

gtcoup

New member
17.8 is wut i get for average mpg says the display in my 97 gt. also ive noticed when i have it on range it bounces around give or take 20 miles. somethings probly fcked up anyideas? i just put a brand new air filter in it and cleaned the plugs. i just bought it and it was sittin for a few months. it had a misfire so i cleaned all the plugs and its runing better. gotta flush fluids and sh1t but i know thats not causein it. im gonna throw some kinda gas treatment in and run it just for kicks but i wanted some input.:o
 


i was thnkin i was maybe a few miles off because i had a 97 se and the gauge was busted i jus went by miles figuring i got 25 mpg and never had a problem. just wasnt sure thanks guys
 
at best i get 30 mpg at worst i get 19mpg and thats drivin like satan on crack. this is with a 200k mile engine
 
im gonna reset it on monday morning when i drive into school. (40 miles on the highway) if im lucky i wont hit traffic so i can cruise at like 70. but i kno i ant gettin nowhere near 30 on the highway and ive been babying this thing for the most part. i dont think ive gone halfway thru the throttle . who knos atleast im back in the prix man it feels good as i crashed my se 3 months ago just picked this up 2 weeks ago i love it. best 500 bucks i ever spent
 


The DIC is pretty brutal for accuracy. I would take its average and range with a grain of salt.

My '98 GTP with a 3.2 pulley and a lead size 14 operating the accelerator gets ~20 on mixed highway/city (mostly highway).
 
17.8 is wut i get for average mpg says the display in my 97 gt. also ive noticed when i have it on range it bounces around give or take 20 miles. somethings probly fcked up anyideas? i just put a brand new air filter in it and cleaned the plugs. i just bought it and it was sittin for a few months. it had a misfire so i cleaned all the plugs and its runing better. gotta flush fluids and sh1t but i know thats not causein it. im gonna throw some kinda gas treatment in and run it just for kicks but i wanted some input.:o

Don't feel bad. My GT gets the same 17.8mpg. Makes me sick cus I don't even drive it like I want to.

at best i get 30 mpg at worst i get 19mpg and thats drivin like satan on crack. this is with a 200k mile engine

How you do that?? I know you're a GTP and all but how can I see mpgs like that??
 
Are the GTP's supposed to be better on gas than a GT if it is staying out of boost for the most part? My GT gets whatever it feels like for gas mileage:mad: sometimes great sometimes bad
 


Well what else can I do to help my MPGs in my GT?
Since I've got it, I've replaced the engine of course. But I have new fuel filter, fairly new plugs (they were used for a month in the 3800 that spun a bearing) with about 2000 miles on it, new air filter, and 34 PSI in the tires for the cold weather we have right now.

The only factor I can see hurting my mpgs is the PO420 that came on a couple days ago.
I get about 17.7 though on average. It can be better now, I don't drive like a mad man...all the time.
 
The Coolant Temp Sensor is like an asshole, everything revolves around it. Check out actual engine temp and see what the car is reading. If it's not in the range it should be replace the thermostat. If that is normal swap that little bugger out. If that little thing is reading cool when the engine is hot, it will enrichen the gas. For some reason GM put the ohm range a little wackier than most others. This has been a fix in quite a few different GM's
 
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