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Better Mileage since ECU Upgrade...

1K views 15 replies 9 participants last post by  is300dawg 
#1 ·
Ok, I'm prepared to make an official statement. After three full tanks of gas and normal driving (for me anyway, mostly aggressive, mostly highway) since my ECU upgrade...

I have gained 2 MPG. I used to never get anything better than 20. Now I'm getting a solid 22. Go figure.
 
#5 ·
SO far no probs with my ECU/TRAC thing (well it did it for two days but no signs of trouble and I can't replicate it when I am at the dealer's). My mileage improved just through putting more miles on it. When I hit 4k miles (I now have 5k), I started to get 22 of combination city and highway. Used to get 19-20 was was getting a little p**ed off. I guess it is getting broken in. It feels alot quicker and smoother too.
 
#6 ·
I've been getting no better than 20 since Day One, so that's why I was really surprised to see it change. And this has been consistent on my last three full tanks.

BLUE, there should be any number of ECU topics on the board at any time. The ECU/Trac upgrade is for early IS's to fix a hesitation in shifting and a too-early traction control engagement.
 
#8 ·
Originally posted by is300dawg:
This really worries me because I am getting an average of 13.5 MPG and that is mostly city driving somewhat aggresively, is this normal?
Most people who know me would certainly say that I drive aggressively - and I've never gotten mileage that bad. Unless you're drag-starting at every light, I'd say you've got a problem.
 
#12 ·
Originally posted by rllis300:
SO far no probs with my ECU/TRAC thing (well it did it for two days but no signs of trouble and I can't replicate it when I am at the dealer's). My mileage improved just through putting more miles on it. When I hit 4k miles (I now have 5k), I started to get 22 of combination city and highway. Used to get 19-20 was was getting a little p**ed off. I guess it is getting broken in. It feels alot quicker and smoother too.
Good there is some hope for my IS, just filled up yesterday and was getting 18mpg combo hiwy/street, with the AC on. Only hav 3500 miles on the car, hoping when it hits 5K I'll see an improvement in gas mileage, as others have reported.
 
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