2002 sat s series 4 door 189000 miles is hard to start and idles rough at 800 rpm, but only in park. When i put the car in gear the rpms go down to about 600 rpm and its smooth as silk.
Hi have you tuned it up lately could be you just need a tune up your spark plugs could be really old that's where I'd start beyond that if you do a tune up and it's still running rough it could be your throttle position sensor it's in your throttle body not sure I can give you any more information other than do a tune up and go from there good luck!
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