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Discussion Starter #1
For some reason my milage has gotten bad 12 - 14 MPG, it seems like there is excessive carbon build up on outside of my exaust tips. Seems like there is about a 1/2 inch on them, car is running good but seems like she is running rich. Anybody elso???????
 

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Sounds a lot like failed oxygen sensors.
 

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Discussion Starter #3
Wouldn't it throw a code? It dosn't, but will have check with my tourq app i guess.
 

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It might. But if it hadn't failed, but just got "weak" and inaccurate, it might still be sending an acceptable signal, and the extreme end of the range.

If you don't want to go to the dealer I would:

Pull the MAF and check the filaments for build up. Over-oiled air filters can cause issues.
Pull both front oxygen sensors and see if they have the same color buildup on them. Maybe that could point you to one side or the other.

Check your fuel trims.
 

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Discussion Starter #5
It might. But if it hadn't failed, but just got "weak" and inaccurate, it might still be sending an acceptable signal, and the extreme end of the range.

If you don't want to go to the dealer I would:

Pull the MAF and check the filaments for build up. Over-oiled air filters can cause issues.
Pull both front oxygen sensors and see if they have the same color buildup on them. Maybe that could point you to one side or the other.

Check your fuel trims.
Already cleaned MAF a few weeks ago with MAF cleaner,haven't oiled filter since instilation.Thought about o2 sensors,are they on exaust after the bend to go under the car?Will check trims tomrrow with tourq app.
 

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There are 2 O2 sensors on each side. One before the cats and one after the cats. Use liquid wrench or wd40 generously before attempting to loosen them.
 

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In the G8 with Solo axlebacks, I used a bottle of RXP gas kicker which not only cleans the injectors, but also cleans the exhaust, oxygen sensors, and a whole bunch of other stuff. If you use it on a relatively old vehicle, it may throw a code as all of the carbon deposits are being pushed pass the oxygen sensors and the car may have some initial hesitation. Put a bottle in the tank. Fill the tank up. Run it through. You SHOULD notice a difference. It's call RXP gas kicker in a small yellow bottle. While you're at it, you might want to go ahead and clean the throttle body as well, and for that I recommend a can of B12 chemtool. GL!!!
 

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Thought about o2 sensors,are they on exaust after the bend to go under the car?
You can actually get at them from up top. They plug right into the exhaust manifold.

-Dennis-
 

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Too rich, Air Filter over oiled, O2 sensors and dirty injectors. I agree check the easiest stuff first. Every 40K miles I decarb the engine and injectors at my mechanic. Gas could pose I problem as well, I can still get NO ETHANOAL. Good luck.
 

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Discussion Starter #11
Do you get gas at the same place all the time?
At BP in fact same pump,did get a rew tanks at Sams club. Have used 93 for a while , seemed to run better when i switched from 87.
 

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Did anyone buy brakes for the base model ? I see the front brakes are 272 00 dollars for the front pads. I about die when i was told.
 

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Did anyone buy brakes for the base model ? I see the front brakes are 272 00 dollars for the front pads. I about die when i was told.
Seems a bit steep but mine were not cheap. Did that include rotors by chance? I had a deal at the place I go. The monthly deal was free pads. I needed rotors as well and It was $385 out the door for the fronts. Each rotor was $100 labor was another 100-150 and then tax and misc. If you go to Autozone / Napa / Advanced I believe you can get standard duralast pads for $50 per axle or $95 for the good pads up front and $80 for the rears. Front rotors are $60 a piece.
 

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Saving Gas and Goin' Slow
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as for the brakes comment, get duralast gold pads.. u can bring them back when the guy out for free at autozone.. winning..

as for gas.. i just got my car 4 days ago and it SAYS ive been getting 18.9 mpg around town, and thats having fun with the new car.. check o2's. when I had my old mustang I got 5mpg more after getting new ones because they were bad.
 

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My goat had the same problem about two years ago, the o2 sensors aside from being dirty had come loose (i unscrewed them by hand when i checked them). Cleaned em out and put them back in properly and it fixed the problem
 
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