still crappy gas mileage. evap valve?

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bradjh
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still crappy gas mileage. evap valve?

Post by bradjh »

after getting a tuneup and a set of spider injectors im still only getin 12-14mpg in city used to get 16-17, throws code po446 if i get on it hard sometimes? what is the part number and how to remove replace it i found the topic but none of pics will show? could this affect milege? what else could cause decrease in mpg?
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Re: still crappy gas mileage. evap valve?

Post by F9K9 »

Do a search for the evap system with HenryJ as the author. He has done extensive research on the topic but, I do not see it affecting your mileage problem.
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bradjh
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Re: still crappy gas mileage. evap valve?

Post by bradjh »

ok got evap prob. solved still geting bad mileage, got 13 mixed city and highway so far I have done new intake gaskets ,spider injectors, oxy sensor just one that was throwin code put a bosch in there, fixed vent valve still not getting my usual milege truck seems to have less power notice on highway when accerlerating, all tires inflated i do not idle truck been noticing a sulfur rotten egg smell when i back in drive way should i have the precat and cat looked at? any other ideas what maybe causing drop in mpg getting frustrated tired of puttin money in truck
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Re: still crappy gas mileage. evap valve?

Post by HenryJ »

Yes. Check the Precat thread. That could also be related to your O2 sensor codes as the readings might be skewed by the plugged cat.

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bradjh
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Re: still crappy gas mileage. evap valve?

Post by bradjh »

ok i am not having any check engine codes at this point, I have also done a full tune up fuel filter, plugs, wires, cap, rotor....
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Re: still crappy gas mileage. evap valve?

Post by HenryJ »

Read the plugged cat thread. Mine set no codes and ran like crud once warmed up.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
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bradjh
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Re: still crappy gas mileage. evap valve?

Post by bradjh »

had pre cat removed and new cat put on , said old stuff was not completely plugged but definitly restricted truck sounds great now and feels like it has allot more power will keep my eye on the mileage have to stop getting on it but i cant resist sounds like a differnt truck
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Re: still crappy gas mileage. evap valve?

Post by F9K9 »

Why is it that sounds make us stupid? I remember when flipping the air cleaner cover upside down on a carbed engine made me want to get on it every chance. :roflmao:
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
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Re: still crappy gas mileage. evap valve?

Post by rlrnr53 »

Reed, I was just thinking about that the other day. I used to flip the lid over on my dad's 68 Impala, that 327 would turn heads when you would get on it. Another memory brought to you by the old geezers club.
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Re: still crappy gas mileage. evap valve?

Post by F9K9 »

:roflmao: :roflmao:
[size=75][b]"For those who have fought for it, [i][color=red]FR[/color][color=white]EE[/color][color=blue]DOM[/color][/i] has a taste that the protected will never know."
[url=http://www.naxja.org/forum/showthread.php?t=73349]GUIDE TO SEARCHING. [i] (Some of the forum software is different but, it has helped me a lot.)[/i][/url][/b]
[b]"Those who don't know history are destined to repeat it." Edmund Burke[/b][/size]