gas mileage went down
Thread Starter
Pro
Joined: Mar 2005
Posts: 665
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From: DON`T MAKE ME BLEED MY OWN BLOOD!!! TX
gas mileage went down
Just bought my car (97) and have changed the stock filter and exhaust.I have put open box filter and and borla stinger cat back.My gas mileage has dramatically drop off from 24 mpg t0 18 whats going on.Is it normal because of gaining much cold air and more horsepower.What should i do.
thanks
thanks
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Check your tire pressure. Should be 28-32 PSI
Check for codes. If you have any, post them.
Make sure that your brakes are not dragging.
Make sure that your NOT leaking fuel. Some C5's leak fuel at the filter.
Is your engine running good??
Is it a manual or automatic?
Most here with a stock C5 get 17-20 City/highway combo & 28-31 Highway crusing at 60-65 mph steady state.
Let us know what you find.
Bill C
Check for codes. If you have any, post them.
Make sure that your brakes are not dragging.
Make sure that your NOT leaking fuel. Some C5's leak fuel at the filter.
Is your engine running good??
Is it a manual or automatic?
Most here with a stock C5 get 17-20 City/highway combo & 28-31 Highway crusing at 60-65 mph steady state.
Let us know what you find.
Bill C
Racer
Joined: Jan 2005
Posts: 428
Likes: 0
From: Punta Gorda FL
After my headers, Blackwing, Magnaflow install I used a Vinci / Crane tuner set for High Performance. Lost 2 mpg even being careful. Need to check for codes. I may have a bad O2 sensor? 92-93 octane just went to $2.50 - 2.55 
