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Q: Idles rough and strong rotten odor coming from exhaust.

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recently replaced distributor cap and rotor, replaced ignition control module, MAP Sensor, 0xygen Sensor, new fuel pump and filter, Air filter, new egr valve, spark plugs... could ignition timing be off? was running good then just started running like crap, still starts right now.

My car has 155600 miles.
My car has a manual transmission.

This may be a sign of a clogged catalytic converter. As you may already know, the catalytic converter converts toxic exhaust gases into less harmful pollutants that are suitable to be expelled into the atmosphere. When this is clogged, this causes these gases to be backed up into the exhaust system not allowing the engine to breathe properly (think of a backed up sink). When this happens, the engine is forced to work much harder to expel these gases. This often results in the engine bogging down, hesitating, shaking and causing very poor fuel economy. This should also cause a check engine light to come on as the O2 sensors should be reading the incorrect amounts of oxygen in the exhaust gases if this is your problem. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your catalytic converter.

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