1988 chevy 2500 4x4 6.2 N/A motor. Had it scanned showed up as mixture control soleniod. Parts house didn't show one, But it did show E.G.R. Solenoid I went ahead and ordered E.G.R. solenoid. Are these parts the same? If not is that mixture control solenoid a dealer Item? The colder it gets the more it acts up. If you ease on the gas when you take off you can feel it come in like it catches up with its self. If you get in the fuel real hard it will run about 20 feet then it falls off or dies if you stay on the gas. I disconnected vacume from EGR valve.It doesn't seem like there is a lot of vacume, but it changes from heat to defrost as good as my gas truck. So I figured it must have enough vacume. Went ahead and changed fuel filter. It's a 1988 with only 50,000 miles on it. Is there a hidden filter on it some where that I just haven't found? I know on gas burners that a fuel filter will swell up if it has been dry for awhile and then you put fuel back to it. I'm kind of new to these diesel motors. i like it, goes about twice as far on take of fuel as my gas truck. Oh yea diesel is about $2.65-$2.85 a gallon around here whats everybody else having to pay.