15 mpg: Halp
11-25-2006, 02:10 PM
#1
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15 mpg: Halp
So heres the situation:
Walbro 190 goes in with 1.8 injectors.. gas mileage drops but isnt TERRIBLE (23mpg). 305s go in, 15mpg. Something just seems terribly wrong beyond normal fuel tuning. The CELs were some ground problem.. and an O2 problem, which was flicking on and off. In an effort to resolve this problem I grabbed an O2 off braineacks old motor which did not solve the problem (23 mpg), and in a further effort I got a brand new bosch o2 from advanced auto (like 20 bucks) which has me at my current 15 mpg. This is running roughly 10 psi @ 105 psi fuel .. 35ish idle psi fuel. To me it sounds ALOT like an o2 problem
Here comes the questions:
My mechanic buddy said I should try an OEM o2 (240 bucks ...uh no) because the standard 20 dollar o2 is probably not handling it right. Is there a real difference between splicing that o2?
Does anyone have any suggestions ?
Walbro 190 goes in with 1.8 injectors.. gas mileage drops but isnt TERRIBLE (23mpg). 305s go in, 15mpg. Something just seems terribly wrong beyond normal fuel tuning. The CELs were some ground problem.. and an O2 problem, which was flicking on and off. In an effort to resolve this problem I grabbed an O2 off braineacks old motor which did not solve the problem (23 mpg), and in a further effort I got a brand new bosch o2 from advanced auto (like 20 bucks) which has me at my current 15 mpg. This is running roughly 10 psi @ 105 psi fuel .. 35ish idle psi fuel. To me it sounds ALOT like an o2 problem
Here comes the questions:
My mechanic buddy said I should try an OEM o2 (240 bucks ...uh no) because the standard 20 dollar o2 is probably not handling it right. Is there a real difference between splicing that o2?
Does anyone have any suggestions ?
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11-25-2006, 02:28 PM
#2
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Sounds like a right foot problem. 
Do you have a wb to monitor afr in the exauhst? I am always better than 25 mpg.
So heres the situation:
Walbro 190 goes in with 1.8 injectors.. gas mileage drops but isnt TERRIBLE (23mpg). 305s go in, 15mpg. Something just seems terribly wrong beyond normal fuel tuning. The CELs were some ground problem.. and an O2 problem, which was flicking on and off. In an effort to resolve this problem I grabbed an O2 off braineacks old motor which did not solve the problem (23 mpg), and in a further effort I got a brand new bosch o2 from advanced auto (like 20 bucks) which has me at my current 15 mpg. This is running roughly 10 psi @ 105 psi fuel .. 35ish idle psi fuel. To me it sounds ALOT like an o2 problem
Here comes the questions:
My mechanic buddy said I should try an OEM o2 (240 bucks ...uh no) because the standard 20 dollar o2 is probably not handling it right. Is there a real difference between splicing that o2?
Does anyone have any suggestions ?
Walbro 190 goes in with 1.8 injectors.. gas mileage drops but isnt TERRIBLE (23mpg). 305s go in, 15mpg. Something just seems terribly wrong beyond normal fuel tuning. The CELs were some ground problem.. and an O2 problem, which was flicking on and off. In an effort to resolve this problem I grabbed an O2 off braineacks old motor which did not solve the problem (23 mpg), and in a further effort I got a brand new bosch o2 from advanced auto (like 20 bucks) which has me at my current 15 mpg. This is running roughly 10 psi @ 105 psi fuel .. 35ish idle psi fuel. To me it sounds ALOT like an o2 problem
Here comes the questions:
My mechanic buddy said I should try an OEM o2 (240 bucks ...uh no) because the standard 20 dollar o2 is probably not handling it right. Is there a real difference between splicing that o2?
Does anyone have any suggestions ?
Reply
0
0
11-25-2006, 04:48 PM
#10
i just filled up. 175 miles, took 9.43 gallons = 18.55mpg, a little better but not much. I'm thinking it might be my maf, but wouldn't make sense in your case. It's also been recommended to my by olderguy to check you thermosensor in the back of the motor which can cause your car to think it's always cold and enrichening the mix.
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11-25-2006, 05:18 PM
#11
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Yeah I was gonna say....I dont even run an o2 sensor. And I still manage to get about 19-23mpg depending on how much I keep my foot in it while driving. I average 19-20 and thats getting into boost 5% of the time, or making a couple 2-3-4 gear runs for ***** and giggles.
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11-25-2006, 10:05 PM
#12
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I wonder if the VPC can't lean up the idle enough on the 305s. Once you get the WB we'll easily be able to figure out what it can/can't do. But I'm averaging 25-27mpg with my 305s.
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11-27-2006, 12:01 PM
#17
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i just filled up. 175 miles, took 9.43 gallons = 18.55mpg, a little better but not much. I'm thinking it might be my maf, but wouldn't make sense in your case. It's also been recommended to my by olderguy to check you thermosensor in the back of the motor which can cause your car to think it's always cold and enrichening the mix.
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