Pro help needed - gas mileage 1990 1 ton

I have a 1990 4X4, 1 ton, 454 chevy. It gets 8.8 mpg with no load - most of those are country miles. I try to drive with a light touch. Shouldn't I
be getting closer to 12 mpg? The engine seems to run smoothly except when the EGR valve sticks and I have to unstick it. I had a mechanic check it out tuneup-wise before I new the gas mileage and he said it was fine.
Where do I start checking? Can someone give a list of what to check?
Thanks! Dan H ----------------- www.Newsgroup-Binaries.com - *Completion*Retention*Speed* Access your favorite newsgroups from home or on the road -----------------
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Dan,
If it's the original 02 sensor, or if the sensor has more than 75k miles on it, it's time for a replacement.
A nice set of plugs and wires will do her well also. I recommend AC Delco Rapidfire Plugs, and Accell Plug wires. Believe it or not, when I swapped a set of new Accell wires into my 1/2 ton they gave me a 1 mpg increase over the new generic wires I had in there.
Doc
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Get a new EGR valve, replace the O2 sensor, new air filter(don't run an open element), check all vacuum lines, clean the TBI, new plugs, new wires, new cap and rotor, torque all TBI and intake bolts, and give EVERYTHING a once over. Replace the catalytic converter with a new one(or eliminate it altogether if you can get away with it(I didn't say that)) and put a good 3inch(minimum) single or 2 1/2inch(minimum) dual exhaust on with good mufflers(NOT glass packs). A set of full length headers would make a BIG difference!!!

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Thanks to all who contributed! I installed a new egr valve and now I'm getting 11.9 mpg! (I went on a trip last night and this AM) Nothing to brag about, but decent. The guy at the parts house where I got the egr valve said it would make it idle smoother, but wouldn't improve the mpg. Wrong.
I'm still going to try the other things too.
Thanks again! Dan H

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