I've recently bought a 2007 Alfa Romeo 159 jtdm 16V. The other day i noticed a lot of white smoke coming out of the exhaust, but it was also coming out of the engine bay. I think it smelled somewhat similar to burnt plastic, but I'm not really sure. I took the car to a mechanic, but he couldn't figure out the problem. He looked for a blown head gasket but that wasn't the case. However, he did find out that the EGR-valve was broken, but he doubted that it would cause the white smoke. So my question is, could the reason for all the smoke be caused by a bad EGR, or what else could be the case?
My car has 50000 miles.
My car has an automatic transmission.
A malfunctioning EGR system may cause excessive raw fuel emissions, that is an odor of gasoline, but not smoke (white or otherwise) from the exhaust. Some smoke at start up can be normal, particularly white smoke from condensation. However, continuous smoking (of any color) after the first few minutes signifies a problem with the engine that you should seek to have identified in an engine smoking diagnostic. If the smoke is white that could be from an antifreeze leak due to a cracked cylinder head or engine block or a head gasket failure (the latter appears to have been ruled out in your case). If the smoke were blue, that would signify an oil leak into the combustion chambers from the valve guides or the rings. Black smoke occurs if the engine is being flooded with gasoline. Of course, multiple engine faults could occur at the same time causing different appearance of the smoke. At any rate, the thing to do to resolve this is seek a diagnostic so that you can determine what repairs will be required. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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