Averaging 9MPG
Thread Starter
Cruising
Joined: Jul 2022
Posts: 13
Likes: 0
Averaging 9MPG
What's going on guys
So I just wanted to see if I'd get any input here before I start digging. Just bought an 86 from a shop. New fuel pump, sending unit, distributor, wires, plugs, maf, etc. However no new injectors. I had an hour drive home with it and I noticed the mpg avg was 7 but gradually went up to 9. Didn't seem as if the fuel level was dropping too fast but regardless still a concern. Considering what's new I'd figure first thing to check would be the o2 sensor, egr, pcv. I did get a CEL on the way home but I wiggled the maf clip and it cleared so i know I need it to hold contact but regardless need to find why it's claiming 9mpg. I read other threads mentioning to check the balancer and check the fuel drain for any clogs but any other ideas let me know thanks in advance!
So I just wanted to see if I'd get any input here before I start digging. Just bought an 86 from a shop. New fuel pump, sending unit, distributor, wires, plugs, maf, etc. However no new injectors. I had an hour drive home with it and I noticed the mpg avg was 7 but gradually went up to 9. Didn't seem as if the fuel level was dropping too fast but regardless still a concern. Considering what's new I'd figure first thing to check would be the o2 sensor, egr, pcv. I did get a CEL on the way home but I wiggled the maf clip and it cleared so i know I need it to hold contact but regardless need to find why it's claiming 9mpg. I read other threads mentioning to check the balancer and check the fuel drain for any clogs but any other ideas let me know thanks in advance!
Melting Slicks
Joined: May 2014
Posts: 2,894
Likes: 592
From: New Port Richey FL
Before you loose your mind that reading is a general average from the last time it was reset, so if the guy you bought it from spent the last 1000 miles Drifting and running car hard it will show poorly and take a while to even out.
So push the resets as a new owner and drive like a Human on the highway for about 30 miles at 65/70 cruise set you should average out 25 plus and instant a bit better
So push the resets as a new owner and drive like a Human on the highway for about 30 miles at 65/70 cruise set you should average out 25 plus and instant a bit better
Thread Starter
Cruising
Joined: Jul 2022
Posts: 13
Likes: 0
Before you loose your mind that reading is a general average from the last time it was reset, so if the guy you bought it from spent the last 1000 miles Drifting and running car hard it will show poorly and take a while to even out.
So push the resets as a new owner and drive like a Human on the highway for about 30 miles at 65/70 cruise set you should average out 25 plus and instant a bit better
So push the resets as a new owner and drive like a Human on the highway for about 30 miles at 65/70 cruise set you should average out 25 plus and instant a bit better
Drifting
Joined: Feb 2016
Posts: 1,384
Likes: 339
From: Simi Valley CA
If that is your actual mpg based on calculating miles driven dividend by fuel used that would be a poor running car or very lopey. A clogged cat would affect performance like that. Easy way to check is use a infrared thermometer before and after the cat. Big difference in temp change indicates a problem.
Drifting
Joined: Jul 2022
Posts: 1,805
Likes: 365
From: Central Florida
Couldn't this be a lot of idling time while working on it , charging battery, moving it around the shop etc ??? Disconnect the battery and idle it a while and you get instant bad/zero mileage.
Reset the fuel mileage and drive it.
Reset the fuel mileage and drive it.
Last edited by Vets-Vet; Feb 26, 2024 at 01:43 PM.
Thread Starter
Cruising
Joined: Jul 2022
Posts: 13
Likes: 0
If that is your actual mpg based on calculating miles driven dividend by fuel used that would be a poor running car or very lopey. A clogged cat would affect performance like that. Easy way to check is use a infrared thermometer before and after the cat. Big difference in temp change indicates a problem.
100%! I bought it on Saturday so haven’t done anything but drive it home. I'll for sure do that thank you
Melting Slicks
Joined: May 2014
Posts: 2,894
Likes: 592
From: New Port Richey FL
Drifting
Joined: Nov 2018
Posts: 1,759
Likes: 647
From: USA
Agreed ^^^^^^ Drive it as much as you can, get as many miles under your belt as possible!!! This is how you can truly evaluate its characteristics, pros and cons, needs and wants.....Basically, you want to establish a known baseline of what you truly have in the car, so you have something to compare repairs/changes to!!!!! IMHO, it's absolutely critical to have a shakedown period before you start tearing it apart and changing/fixing things! Obviously, this does not apply to problems like overheating, brake pedal that goes to the floor, etc...issues that would constitute parking the vehicle until fixed!!! But you can know you need new shocks and still drive it, start a list of "needs" and a list of "wants" and get to "know" your corvette first....This will absolutely help with having a positive attitude in the future when it does need work, because it'll be your "baby"...not that "f-ing POS"👍
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Thread Starter
Cruising
Joined: Jul 2022
Posts: 13
Likes: 0
Agreed ^^^^^^ Drive it as much as you can, get as many miles under your belt as possible!!! This is how you can truly evaluate its characteristics, pros and cons, needs and wants.....Basically, you want to establish a known baseline of what you truly have in the car, so you have something to compare repairs/changes to!!!!! IMHO, it's absolutely critical to have a shakedown period before you start tearing it apart and changing/fixing things! Obviously, this does not apply to problems like overheating, brake pedal that goes to the floor, etc...issues that would constitute parking the vehicle until fixed!!! But you can know you need new shocks and still drive it, start a list of "needs" and a list of "wants" and get to "know" your corvette first....This will absolutely help with having a positive attitude in the future when it does need work, because it'll be your "baby"...not that "f-ing POS"👍