Question about 1995 Oldsmobile Ninety Eight

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Had motor replaced in 1995 Olds 98. Gas mileage went from (old) 32 MPG to 25 MPG. 2000 miles on new engine. What gives?

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If you are using an EFI engine and the old computer module is still used, have it reset first. It may still have the data from the old engine. If you are using an old engine, you may have to do additional inspection and see if there are worn out parts. For crate engines (brand new) it would need a break in period, normally less than 800-1000 miles.

Posted on Dec 11, 2009

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1 Answer

How to increase mileage in a 1998 olds 88 royle with a 3800 engine

tune up carburetor, wheel alignment, tire balance, rotate tires, put a fuel cleanser in your gas tank. hook up to a computer for other problems related to car.

Jun 18, 2014 | 1998 Oldsmobile 88

1 Answer

Low gas mileage city and hiway @ 4-5 MPG below MSRP sticker data of 15 and 21MPG on a NEW 2013 Silverado. 2000 miles on odometer and mileage not improving.

is this calculated mileage or what the estimated mileage is showing on the dash. Have you checked to see what you get on just the freeway?

What are your driving habits like?

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Do you make a lot of short trips?

I’m happy to assist further over the phone at

Apr 11, 2013 | Cars & Trucks

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My 1992 isuzu pickup use too much gas. how can I inprove my mpg.

I'm not sure of the mileage on your truck, but there are a number of things that you can do to improve your gas mileage. If the truck has over 100,000 miles, the next time you change your oil you can choose engine oil that is specifically designed for high mileage vehicles (make sure that it is the correct weight for your vehicle) Change your air filter, this has alot to do with fuel efficiency. Make sure that you get your tires rotated and balanced every 5,000 miles. Also check your tread wear on all 4 tires. If you have significantly uneven tread on your tires this can have a drastic effect on mpg. Check your plug wires: if they look worn and old replace them. If they appear to be in good shape then you can get away with only getting new spark plugs. If you are really dedicated to the truck you can always opt for a fuel system flush at your local service station, I know they offer this service at Midas in my area for $99. Lastly I used to have 98 Stratus that got poor gas mileage. I started putting a bottle of the STP treatment (in the black bottle not red) during every fill up and it averaged an extra 40 miles per tank. Hope this helps.

Mar 28, 2011 | 1992 Isuzu Pickup

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My Mother-in-law age 86 drove her 95 Olds Ceria to the grocery and when she came out it would not start. It was fine when she went in to the store. It has 35,000 miles on it. What do you think happened?

sounds like the fuel pump went out, a fuel pump doesnt go out by mileage all the time they can also go out do to age the car being a 95 makes the car 16 years old so that is the first thing i would check take off the gas cap and put your ear to the nozzle and have someone turn the key to the on possition and listen for a humming sound if it doent make a sound your fuel pump is defintely went out. hope this helps.

Jan 02, 2011 | 1995 Oldsmobile Cutlass Ciera

2 Answers

What is the mpg for 84 olds delta 88 royale brougham

Hard to say on a older car such as this. If running well and healthly it should receive around 16 to 18 highway miles per gallon

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3 Answers

98 dodge caravan uses lots of gas

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1 Answer

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The better the engine breaths the better the mileage. Was the new computer a stock computer or performance?

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1 Answer

1995 Olds 98 had oil pan gasket replaced. Oil lite came on,

The oil pump broke down or the oil pickup was blocked not feeding oil to the engin. The bad news, the engin is probely ceised and will cost a lot of money to repair, if it is repaireble.Alternetive is to replace the engin. Could be cheaper than repair.

May 18, 2009 | 1995 Oldsmobile Ninety Eight

2 Answers


AC temp mode control motor.

Jan 06, 2009 | 1995 Oldsmobile Ninety Eight

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