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QUESTION: Tom I have a 2013 corvette grand sport that I bought new and now has 3500 miles. From day one the gas mileage has been 18 highway in 6th gear at 65mph. This is my second vette last being a '12 coupe and the corvette has a known highway mileage of 26 and thats being conservative. The '12 coupe I had consistently got 26-29 on the highway as do all my friends vettes. Car runs perfect ( other than a little lumpy idle now and then but my last one also did and most of them do anyway )so its baffling why. Car is a 6.2 6sp manual. Even though it runs perfect would a ecm reflash help? Couldn't hurt no? I really don't want the dealer poking around my motor too much as I'm not sure I totally trust their mechanics to be corvette techs.
Thanks RON

ANSWER: HI RON, GREAT CAR C-6..I AM GLAD YOU LIKE IT. I OWN A 2010 ZR1..I LOVE IT TO DEATH !!!I DO NOT DRIVE IT MUCH. 157 MILES OR SO I GUESS. BUT WHAT A BLAST..OK AS TO YOUR PROBLEM,YOUR NUMBERS ARE VERY LOW. WHAT BOTHERS ME IS THAT YOU SAY THE ENG RUNS GOOD. WITH THIS KIND OF MIL I WOULD THINK THE ENG WOULD BE RUNNING ON 5 CYL'S . I WILL ASSUME YOU ARE DRIVING THIS THE WAY YOU SHOULD SHIFTING IN THE CORRECT GEAR AT THE CORRECT RPM. YOU HAD GOOD GAS MIL WITH YOUR LAST VETTE SO I DO NOT THINK THIS IS THE PROBLEM..DO YOU DO A LOT OF SHORT TRIPS. COLD STARTS SHORT RUNS ?? TIRE PRESSURES ARE OK. DUMB QUESTION..HAD TO ASK. YOU ASK ABOUT A REFLASH !!!THIS WILL ONLY HELP IF THERE IS A REFLASH UPDATE FROM GM FOR FUEL MANAGEMENT CONTROL WHICH THERE COULD BE. YOU COULD GOOGLE THIS AND CK FOR TECH SERVICE UPDATE OR CK THE VETTE FORUM. YOU ARE A MEMBER AREN'T YOU ?? GET ON THE CORVETTE FORUM AND FIND OUT OR CALL YOUR DEALER..BUT YOU SHOULD TAKE IT IN TO YOUR DEALER AND HAVE THEM DO A DATA SCAN ON THE OXYGEN SENSOR. MAYBE ONE OF THE O2 SENSORS ARE OUT OF SINK..THIS SHOULD BE VERY EASY TO DO AND YOU SHOULD NOT HAVE TO WORRY ABOUT THE TECHS MESSING UP YOU CAR..THEY KNOW THAT OWNERS OF VETTES ARE VERY FUSSSSSYYY..LET YOUR DEALER KNOW ABOUT YOUR CONCERNS UP FRONT.....THIS IS ALL I CAN THINK OF. LET ME KNOW HOW THIS GOES FOR YOU,GOOD TALKING TO YOU ,TOM..

HI RON,,SORRY TO BOTHER YOU AGAIN,BUT IS WAS THINKING ABOUT YOUR PROBLEM. YOU COULD TAKE YOUR VETTE TO YOUR LOCAL CORNER SERVICE SHOP [IF YOU HAVE ONE THAT IS] AND HAVE THEM DO A DATA SCAN ON THE PCM TO CK FOR FUEL TRIMS. YOU WANT THEM TO BE AROUND -0- THE CLOSER THE BETTER FOR BEST FUEL MI. THAT WOULD TELL YOU RIGHT AWAY IF THERE IS A RICH OR LEAN CONDITION. YOU COULD THAN TAKE THAT INFO TO YOUR CHEVY REPAIR SHOP AND TELL THEM ABOUT IT..THAT WAY THEY KNOW THAT YOU ARE SOMEONE THAT THEY CAN NOT FOOL AROUND WITH !!!!! ONE LAST THING, DID YOU HEAR ABOUT THE PROBLEMS THAT CHEVY IS HAVING WITH THERE VETTE RACK AND PINION STEERING GEARS ??? 2011 TO 2013 NOT ALL VETTES HAVE THIS PROBLEM. IF YOU TURN THE WHEELS LEFT AND RIGHT IN A TIGHT SPOT WITHOUT MOVING THE CAR YOU CAN BREAK THE MAGNETS OFF THE STEERING GEAR CAUSING A CLUNK WHEN YOU TURN LEFT TO RIGHT.[NO DANGER] JUST ANNOYING. THIS IS FOR THE VARIABLE ASSIST STEERING..SO TURN THE WHEELS WHILE THE CAR IS MOVING THIS PUTS LESS STRESS ON THE RACK AND PINION GEAR..TO TELL IF YOU HAVE THIS PROBLEM,START THE CAR WITH THE STEERING STRAIGHT AHEAD POSITION,NOW JUST ROCK THE WHEEL LEFT TO RIGHT IF YOU HEAR A CLUNK CLUNK SOUND. YOUR CAR IS INFECTED WITH THIS..I AM SURE YOU DO NOT WANT TO TAKE YOUR NEW VETTE IN FOR A NEW RACK RECALL. IF THIS DOES HAPPEN, THEY ARE USING [[[REBUILT RACKS]]] NOT NEW...LET ME KNOW WHAT HAPPENS WITH YOU FUEL MI PLEASE..GOOD LUCK TO YOU,,TOM..





---------- FOLLOW-UP ----------

QUESTION: Tom you are one thorough person and I don't get this kind of service at the dealer. Of course you can bother me ANYTIME!. Anyway funny you should mention the rack because my car came with a bad one from the factory! When I picked it up from the dealer with 20 miles on the clock ( car was a hold at factory after being built for a random quality control check and I still got the car with a bad rack!) I noticed a clicking at the center position of the steering wheel and immediately told the service dept before I drove it out. They confirmed and they put a rebuilt GM rack in it. Rebuilt! I was livid but they said they could do nothing about it and this is GM's procedure for this problem. I did look into this problem as other forum members have had it happen to them and they all got rebuilt racks. BTW yes I am a forum member and visit the forum daily with over 1400 posts. I can't believe you mention the rack issue and I am one of them. Go figure. I will take your reply and show the dealer and let them do the procedure. Now they know I'm in touch with someone who probably knows more than they do! Tom you are a corvette brother who definitely knows his shit and your knowledge of chevy products is incredible. I totally value and trust your automotive knowledge which is nothing short of brilliant! I will keep in touch and let you know what happens. Thanks again! RON

Answer
THANKS RON FOR THE VOTE..I JUST WANTED TO KEEP A VETTE MEMBER UPDATED !!! I SEE YOU ARE IN NY..I AM IN ROCHESTER..LET ME KNOW HOW IT GOES..TOM....
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HI RON,I AM JUST CURIOUS ABOUT WHAT THE DEALER DID ABOUT YOUR POOR FUEL MI...WHEN YOU HAVE A MINUTE GET BACK TO ME ON THIS IF YOU CAN..THANK YOU VERY MUCH,, TOM.

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TOM SHEETS

Expertise

PLEASE READ ALL OF THIS BEFORE ASKING ANY QUESTIONS. IF THIS CHEVY SECTION IS MAXED OUT.YOU CAN REACH ME IN THE OLDS/BUICK SECTION. Will answer questions from 6:00am to 10:00pm all days [EST][[[ NO DIESEL OR PAINT QUESTIONS]]] will answer all 1965 to present QUESTIONS ON ALL GM'S on mechanics of these cars. Keep in mind i am not there in person i am going on what you are telling me !! PLEASE IF ASKING A QUESTION GIVE ME AS MUCH INFO AS POSSIBLE. THE MORE THE BETTER. SUCH AS YEAR,MAKE,MODEL,ENGINE SIZE. THIS WILL HELP ME HELP YOU. I will not be able to answer all questions because of some situations that i would really need to be there and see things for myself,such as electrical issues. In many cases i would need wiring diagrams. I can also give you an estimate on what the cost would be at our repair shop as an idea to help you. Keep in mind that my answer is ONLY MY ADVICE,ck with your mechanic as well.. >> THANK YOU, TOM..

Experience

I have been a ASE certified master mechanic for over 30 years and certified IN ALL 8 CATEGORIES,[engine repair,engine performance,auto trans,manual trans,clutches,steering and suspension,brakes,electrical systems,heating and air/cond. I am also a state CERTIFIED inspector for over 30 years. I do computer work [pcm]fault codes,pcm flashing,state inspection monitor readiness,repairs on exhaust,fuel service,[injection and carburetor,] charging system problems, running issues,alignments,frame problems,tire balance,struts and of course standard and anti-lock brakes.

Organizations
nys state auto repair industry and ase group.

Publications
N/A

Education/Credentials
high school,4 years of tech school,and many many hours of auto training with many gm classes and aftermarket training classes..

Awards and Honors
ASE MASTER TECH CERTIFIED IN ALL 8 CATEGORIES.NYS INSP LICENSE AND A/C CERTIFIED

Past/Present Clients
MANY CUSTOMERS IN OUR BUSY SHOP.

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