1991 Cadillac Deville Loss of power

1991 CADILLAC DEVILLE
90,000 MILES • V8 • FWD • AUTOMATIC
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JAKERIN
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Two owner car. On cold starts it runs rough and seems to smooth out when warm. Loses power on the freeway and mileage has dropped in half. Hard to keep it above 58 mph on a hill where I used to run whatever speed I wanted. Some surging and some 'slow downs' on the freeway. No engine noises at all, great maintenance history and a recent tuneup with one injector replaced. No oil loss but terrible gas mileage. Injectors? Valves? Thanks, Terry
Feb 4, 2008 at 11:00 PM
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BUZZSAW
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[quote:99f59579ad="jakerin"]Engine problem
1991 Cadillac Deville V8 Front Wheel Drive Automatic 90000 miles
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Two owner car. On cold starts it runs rough and seems to smooth out when warm. Loses power on the freeway and mileage has dropped in half. Hard to keep it above 58 mph on a hill where I used to run whatever speed I wanted. Some surging and some 'slow downs' on the freeway. No engine noises at all, great maintenance history and a recent tuneup with one injector replaced. No oil loss but terrible gas mileage. Injectors? Valves? Thanks, Terry[/quote:99f59579ad]

scan the codes for me, off and warmer on the heater control head, with key in the on posision. Write them down, they will display on the control head

what was done on the tune up? May also want to get a top engine clean
Feb 5, 2008 at 1:06 PM
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