C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

9 M.p.g????

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Old Oct 5, 2004 | 12:29 PM
  #1  
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pimpjames
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Default 9 M.p.g????

Any ideas why my car is getting 8.9 - 9.4 M.P.G? It seems to be running good but first thing in the morning takes a min. to start and usually throws up the service engine soon light untill it warms up and I turn it off and bakc on.
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Old Oct 5, 2004 | 12:30 PM
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I used to get about 28mph on the freeway, now I get 14mpg. Thing is, I know for a fact my fuel injectors are having problems. All of them. Maybe that would be a good place to start, by testing the injectors? I just haven't gotten around to (or able to afford) replacing mine yet.
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Old Oct 5, 2004 | 12:43 PM
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i would also look into your oxygen senser do that first.
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Old Oct 5, 2004 | 12:43 PM
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Pull codes and let us know what you get. I tend to agree with Corvettaholic in that it's likely an injector issue. You may have one or more leaky injectors hence the hard starts when the fuel floods the cylinders and has to wash out before she fires. This will usually throw a code or two like for example a 45 for rich exhaust.
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Old Oct 5, 2004 | 04:33 PM
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you got a check engine light... pull the code, it'll most likely tell you why your mileage sucks
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Old Oct 5, 2004 | 05:08 PM
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Or do you drive fast. That isnt good on gas
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Old Oct 5, 2004 | 06:13 PM
  #7  
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I do ... use the gas to clean those lines out ha ha ha ha. but as far as the codes how do i do it? I don't have a tool and am not sure if it is like some vehicles where you turn the ignition on three times and wait for the blinking.
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Old Oct 5, 2004 | 06:44 PM
  #8  
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Originally Posted by pimpjames
I don't have a tool and am not sure if it is like some vehicles where you turn the ignition on three times and wait for the blinking.
If you have access to a paper clip, you have the tool. After you pull your codes, we can help you interpert them, but you are going to need more to deal with them, intellegently. Get your credit card out, and go HERE.

RACE ON!!!
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Old Oct 5, 2004 | 06:45 PM
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You should post what year yours is in your post that would make things easier for us...
anyway- i see from your profile, you have an '86, L98... Find the diagnostic module below the drivers side dash. Take a paper clip, short the A and B terminals together. Turn the key to the Run postion <b>do not start the car</b>. You'll hear the fan come on and your check engine light will start to flash....
first code 12 three times...
*flash once* pause *flash thrice* (three times)
any code you get will appear next
it will finish by flashing code 12 three more times

the first group of flashes is the first number, the second group of flashes is the second number... i.e. 3 flashes, followed by 4 flashes woudl be a code 34...
good luck
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