Well I don't think your muffler is causing the rough idle. It could be an injector or it could be compression. What I think you should do is a compression test. You need a compression test kit to do that. Maybe your mechanic could do it for you. But if it runs good, just a little shabby on the idle, maybe just live with it. Does the idle improve when you pull it out of gear? If it does maybe the idle speed is to low, and it can be difficult to increase as there is no adjustment screw.

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Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
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