The 90's Imperial has an early version of the check engine light and diagnostics retrieved by cycling the ignition key. Try this and see if your Imperial tells you anything: http://allpar.com/fix/codes.html I would suspect an O2 sensor as when they fail, they fail rich. If it were my car, and the O2 sensor was bad, I'd change the oil afterwards. You may run so rich all the gas is not burning. Also, if the roughness is from the engine, you could have a plug, plug wire or coil pack problem too. And don't overlook the air filter while you are checking things out. Mark 1990 Chrysler Imperial 1991 Plymouth Grand Voyager LE 1994 Chrysler LeBaron LX convertible 1997 Dodge Neon Highline sedan Atlanta, GA -----Original Message----- From: mailing-list-owner@xxxxxxxxxxxxxxxx [mailto:mailing-list-owner@xxxxxxxxxxxxxxxx]On Behalf Of Jim Gathmann Sent: Saturday, March 01, 2003 6:13 PM To: mailing-list@xxxxxxxxxxxxxxxx Subject: Re: IML: sick '93' Imperial Bumpy ride, rough ride might be shocks/suspension. Gas mileage may be the efi system however. For instance, the computer uses the oxygen sensor to see how rich/lean you are and fine tunes the engine based on this information. If the o2 is off or bad, things may not run perfectly- and gas mileage would suffer. Other things could also play into effect on this, such as tranny problems, error codes, etc. --- Yvonne Bowhay <moongardenart@xxxxxxxxx> wrote: > > hello it's me again my Imperial beauty is sick > it's grtting terrible gas mileage. (something I > can't deal with, with the price of gas) it's also > shaking or shimmining we think it's the tires, what > is the best tires for my baby? we plan on putting > new shocks on it, maybe that's it . i only want the > best for her, she has to take us to Reno again not > to mention Montana, i'm just worried about her any > suggestion from other 93 Imperial owners would be > helpful. I had no idea Imperials were around for > so long I know I love mine. > > Thanks Yvonne and MIke > > > > > > --------------------------------- > Do you Yahoo!? > Yahoo! Tax Center - forms, calculators, tips, and more __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, more http://taxes.yahoo.com/