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2G Horrible gas mileage why?

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fix the check engine light....complaining about fuel mileage and not worrying about a fuel solenoid problem? think about it.
 
If I am hard driving in boost everyday in town I get ~220 per tank.

If I spend a week babying it I get ~240 per tank.

I am also on a manual transmission. Your auto numbers don't seem too far off the mark unless of corse you have been getting stellar numbers prior to noticing the drop.

You didn't mention any change in driving habits or previous vs current milage per tank though.

How far off are you from your previous MPT?
 
Your asking for help but wont fix an issue you already know about! Go fix them first then come and ask us for help! You may not think its related but it could well be and it might tell another thing to add more fuel etc.

Fix the code(s) Fix the part clear it all then start again and ask for help
 
Oh and for the record nornally get about 25mpg on a cruise and its a 97 auto.
 
If the fpr is not bad, put money elsewhere.

The solenoid will cost you about $100. A vendor on ebay has 4 that he's trying to sell. He says he is affiliated with Mitsubishi and has a warehouse. Here is his link- http://www.ebay.com/itm/MITSUBISHI-...LENOID-VALVE-/171599879642?afsrc=1&rmvSB=true

Do a leakdown test to see if you have a boost leak. A boost leak will ruin gas milage.

A bad 02 sensor should throw a check engine. It's part of the emissions testing process done by the government.
 
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do a boost leak test, true a failed o2 could cause it if its far enough gone, but also dont forget a dirty air filter can casue loss in mpg also. Did you use ngk plugs or a diferent brand? and fixing the code would def help out also even if " not to worry about it"
 
Dude-
You've got some solid replies about the o2 sensor and the boost leak test. However, fixing your CEL which is also pertaining to your fuel issue could solve the problem. Fuel solenoid can be a mpg robber!
 
also with the scanner if they know what they are doing they can watch the switching frequency of the o2 sensors.
 
some scanners for the cel also can do testing for all sorts of things from emissions testing to cheating o2 sensors, and as for fuel problems have you traced all your fuel lines for any cracks holes or leaking fittings.its outta the normal to find one but better to be safe than sorry.
 
I believe bypassing the fuel solenoid would fix the mileage problem even if it's temporary. Mine went bad and connecting the vacuum lines from the manifold straight to the fuel pressure regulator seemed to have fixed my bad mileage. Wont fix the check engine light, but worth a shot. Either way, deal with that solenoid first and go from there.
 
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