Q: new timing belt and new plugs it runs rough

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new timming belt and new plugs it runs rough why.

My car's transmission is unknown to me.

If the rough running started AFTER the belt was installed, it is possible that the new belt is mis-positioned and/or the ignition timing adjustment at the distributor is wrong. Generally, rough running is due to a mechanical (e.g., uneven cylinder compression and/or valve issue) or ignition, fuel, or air induction faults. Plugs, by the way, are merely one component of the ignition system. So, for example, new plugs won’t solve an ignition system problem if you "also" have defective plug wires or a problem with the distributor. In your circumstance, if the timing belt was properly installed and the base ignition timing, and timing advance, are within spec., an engine Diagnostic has to be performed to identify the root issue(s). This is a standard, and quite common service, and YourMechanic performs uncounted of these daily on a mobile basis. Feel free to inquire so that we can see if your vehicle can be restored to good running condition.

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