Hi guys, I have a 2005 Yukon SLT with 283,000 miles on the 5.3 Vortec. I live in Vermont so needless to say the winter has been absolutely brutal. Lately I have been having the problem of a decently rough idle when the engine is cold. It sputters and is obviously misfiring. When the engine is really cold it will show the "Class A Misfire" blinking check engine light, but all I have to do is restart the car and that goes away. Once the engine is warm it idles a little better, still rough but runs fine under load between 1500 and 3000 RPM. I've got bad valve seals so there is a little bit of oil leakage into the cylinders, so I am sure that the plugs could use a cleaning. I also have been having low idle oil pressure problems, thinking I need to replace the pump and pan gasket as read on another thread. I never had this problem in the warm weather, only when it sits outside in the 0 degree temps. Was wondering if anybody else was having this problem, is this a major issue with my engine that needs to be addressed leading to $$$ (just a poor college kid), and are there any immediate remedies that I can do to help the problem? Thanks a lot, appreciate all the help.
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