the car is pinging real bad do I need to repace the timimg chains?
As you probably know VR6s take 91 octane or higher, no questions. Anything lower will probably cause pinging, and if your knock sensors aren't working properly the timing can't be retarded in the affected cylinders. If you're using 91oct+ and the knock sensors are ok, it's most likely a blown head gasket. Open the oil filler cap and see if there's a milky substance on the underside of the cap. Get a compression test done. Keep an eye on the coolant level. When the HG is blown coolant will make its way into the cylinders and sump. When the coolant burns inside the cylinder it creates the excessive smoke you mention. Some of the coolant ends up in the oil, which is why you should check the underside of the filler cap. Good luck!
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