I have a 1997 c280 6 cyl i have replaced the spark plugs,wires,coil,fuel inj 3 and4 and the car still runs rough it will go good for a while and when i give it gas it runs rough and the check engine light goes on i am baffled at what to do next?

On any OBDII vehicle with driveability issues, the first thing to do is check the codes.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

X2 Code readers are cheap. Knowing what the computer is trying to tell you... priceless.

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On some nights I still believe that a car with the fuel gauge on empty can run about fifty more miles if you have the right music very loud on the radio. - HST

1983 300SD - 305000
1984 Toyota Landcruiser - 190000
1994 GMC Jimmy - 203000

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