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Need advice lost 50 miles per tank of gas after BOV install

4K views 9 replies 8 participants last post by  t147 
#1 ·
Hello everyone, its been a while since I posted and I need some help/advice. Niki got me a turbosmart dual port BOV recently and I noticed I have lost 50 miles per tank of gas since the install. I adjusted the BOV to what I believe is the proper setting for it to be at and I have not gained back any of the 50 I have lost. My driving habits have not changed and I am thinking maybe a spark plug might have gone bad in the process? I have only 18,000 miles on the car, its a 2008 and the only other modifications I have done is a CP-E SRI and Rear mount but as I mentioned the fuel loss was after the BOV install. Does anyone have an idea what the issue might be? Thanks in advance

-Andreas
 
#3 ·
Interesting situation here, I haven't been monitoring my MPG but haven't really noticed a difference in fuel consumption between the TS BOV and the stocker. Got a few questions here:

Have you already reset the ECU just for kicks?
Have you checked your plugs for fowling yet?
Are you running the Denso Step Colder plugs?
Just in case, I know it's not on your mod list, but are you tuned?
 
#4 ·
[quote author=Quintin_Poole link=topic=193000.msg4063522#msg4063522 date=1309750547]
I would try to go back to the stock bpv, see if it is still bad and if it still is then it must be something else. Is your air filter clean? Are you running in full recirc mode as well?


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[/quote]

Yes my air filter is clean and i'm running it 50/50[quote author=Ramen_Noodle link=topic=193000.msg4063731#msg4063731 date=1309811445]
Interesting situation here, I haven't been monitoring my MPG but haven't really noticed a difference in fuel consumption between the TS BOV and the stocker. Got a few questions here:

Have you already reset the ECU just for kicks?
Have you checked your plugs for fowling yet?
Are you running the Denso Step Colder plugs?
Just in case, I know it's not on your mod list, but are you tuned?
[/quote]

no i have not reset the ecu.
i have not checked my plugs for fowling, figured i would ask on here if that would be the cause of it before i checked them.
no i'm not running on the denso step colder plugs, think that would help?
and no i'm not tuned.
 
#5 ·
disconnect the battery and reset the ecu. Everytime you change something that will effect the engine you should do this. After resetting drive around mildly for about 50 miles. Then see if there's a difference. Also, have you been driving with the a/c on more often? do you normally use the same brand of gas?
 
#6 ·
I'm not an expert on BOVs but stock is full recirc and enters after the MAF so the car has already measured the air and meters your fuel accordingly. Now your running 50/50 and releasing some measured air but the car is still metering the fuel for all the measured air. So I'd assume you're running rich hence the lower MPG. I wouldn't think it'd be that drastic though.
 
#7 ·
[quote author=Grumpyjap link=topic=193000.msg4064216#msg4064216 date=1309881209]
disconnect the battery and reset the ecu. Everytime you change something that will effect the engine you should do this. After resetting drive around mildly for about 50 miles. Then see if there's a difference. Also, have you been driving with the a/c on more often? do you normally use the same brand of gas?
[/quote]

I'll disconnect the battery to reset the ecu. as far as the a/c goes it's been the same and yes i usually try and stick to the same brand of gas. thanks for the suggestion i'll try it out and let you know if that changed anything
 
#9 ·
[quote author=DreSpeed link=topic=193000.msg4064378#msg4064378 date=1309895527]
[quote author=Grumpyjap link=topic=193000.msg4064216#msg4064216 date=1309881209]
disconnect the battery and reset the ecu. Everytime you change something that will effect the engine you should do this. After resetting drive around mildly for about 50 miles. Then see if there's a difference. Also, have you been driving with the a/c on more often? do you normally use the same brand of gas?
[/quote]

I'll disconnect the battery to reset the ecu. as far as the a/c goes it's been the same and yes i usually try and stick to the same brand of gas. thanks for the suggestion i'll try it out and let you know if that changed anything




[/quote]

There is only one way to know for sure: Check long term fuel trims with the stock BPV vs. the Turbosmart.
Don't bother disconnecting the battery. The ECU is always "learning" (i.e. adjusting the fuel trims).
 
#10 ·
Do a search. There had been quite a bit of discussion on this. there is even a diagram and an explaination between me and another member as to what happens you are using a VTA BOV.
 
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