So I've been thinking about this non stop lately...
Oh btw I did get my header wrap in already, Thank you Serban for freaking fast shipping!
So back to the idea... In October is when I installed the header and regrounded my MAF. Well shortly after I had to take a 270 mile trip, 135 one way on one day, then the rest the next day.
Well then I got my all time lowest highway MPG, even though 30 miles was bumper to bumper traffic, I got about 27 MPG.
When I was at the location, I regrounded my MAF to a better location, Intake Mani, to get 29ish MPG coming back, same deal 30 miles traffic, rest highway 70mph. Now I used to get 33mpg highway in the past...
So, I've been thinking it has been the header since day one, because that was the bigger mod. My friend said that the car probably running too rich. People here on the forum said that, that was a silly idea...
But now thinking back on it... I think it is probably the case.
So the O2 sensor is pretty low on the header gives out a lot of heat before it hits the O2 sensor... Thus the O2 sensor sends a message to the ECU, the ECU thinks that the car is running too lean. Thus adds more gas.
How plausible is that? I think one real way to find out is by installing the header wrap
So I'm going to hold a more of a controlled experiment here. I will drive my car until the gas goes to empty and the light comes up for about 30+ miles, to get rid of any crappy gas that I might have in there.
Then I will fuel up with 93 Shell V-Power gas, which contains up to 10% ethanol. I will then reset the ECU, drive for couple days, then fuel up full and drive about 50 miles and see what I get.
Then I will try to wrap the header, reset ecu, drive couple days, fuel up, drive 50 miles and see what MPG I got.
After that I will test the performance gains from the header wrap, by using the legendary butt dyno