gas mileage
#1
gas mileage
a few months a ago my 92 deville was getting 24.8 MPG and over the last few months it has dropped to 21.6 MPG where it is now, i tried fuel injector cleaner and that did not help my mileage any. my driving style is the same and i have always put 93 octane gas in it? any suggestions on why and how could i get my mileage back to where it was? thanks
#7
RE: gas mileage
It may not hurt to check them and change if needed.
I just got my first Caddy, a '97 Deville D'elegance, at the end of September. Since I don't know the history, I've been going over things one by one. Like changing the oil even though it said there was 48% life left (did someone simply reset it without actually changing it?). On my first long highway trip with it it ran fine on the first leg but developed a strange "missing" on the return trip, which got worse over the following week (no SES). Most of my research indicated plugs and wires. So I bit the bullet and got them, and much to my surprise this engine is the easiest 8-cylinder I've ever changed plugs on! All they plugs looked about the same, minor deposits etc, but I found the #1 plug wire had a cut in it, down into the carbon. The "missing" is gone, runs a bit better than before.
I have not had my car that long, but after a trip to visit the grandkids a few weeks ago, the average MPG on the car (dash indicator) was 26.8. On paper it was 28 - even on a couple of tanks of 91 octane, which seems to be the best you can get in Kansas/Missouri area. It was the best 600+ mile one-way trip we have taken to date! This car replaced a '92 Olds 98 Touring Sedan with over 200K. Before developing severe electrical issues last year it would routinely achieve 30-32 with a supercharged 3800. I thought my T/S was comfortable (3 major back surgeries so far) and was a little upset when Oldsmobile went orphan, but I believe I found a suitable replacement.
Tom
I just got my first Caddy, a '97 Deville D'elegance, at the end of September. Since I don't know the history, I've been going over things one by one. Like changing the oil even though it said there was 48% life left (did someone simply reset it without actually changing it?). On my first long highway trip with it it ran fine on the first leg but developed a strange "missing" on the return trip, which got worse over the following week (no SES). Most of my research indicated plugs and wires. So I bit the bullet and got them, and much to my surprise this engine is the easiest 8-cylinder I've ever changed plugs on! All they plugs looked about the same, minor deposits etc, but I found the #1 plug wire had a cut in it, down into the carbon. The "missing" is gone, runs a bit better than before.
I have not had my car that long, but after a trip to visit the grandkids a few weeks ago, the average MPG on the car (dash indicator) was 26.8. On paper it was 28 - even on a couple of tanks of 91 octane, which seems to be the best you can get in Kansas/Missouri area. It was the best 600+ mile one-way trip we have taken to date! This car replaced a '92 Olds 98 Touring Sedan with over 200K. Before developing severe electrical issues last year it would routinely achieve 30-32 with a supercharged 3800. I thought my T/S was comfortable (3 major back surgeries so far) and was a little upset when Oldsmobile went orphan, but I believe I found a suitable replacement.
Tom