fuel mileage down??
Thread Starter
|
Junior User
Joined: Jan 2003
Posts: 59
Likes: 0
From: NE
fuel mileage down??
A few weeks ago I made my factory airbox look like swiss cheese with my 3/4 unibit, also installed a k/n air filter. Maybe it was just bad timing with winter here, but my fuel mileage went from 15.9 to 13.8-14.6 after the mod to the airbox. Did I do something to the computer system when I disconnected the driver side battery to remove the airbox? Also now when it is cold and your driving down the street it sound like on of the intercooler hoses fell off. It doesn't sound like that when its warm though. Any thoughts other than crappy winter blended fuel?
Senior User
Joined: Nov 2003
Posts: 165
Likes: 0
From: Illinois
Two ideas: Your Back Pressure Valve, or turbo surge/stall--(a common problem with open element and higher volume intakes. )
Since you said it was only on a cold motor I would guess it is the EBPV. If it is, just gut the damn thing and be done with it.
The other possibility (slim chance)
Turbo stall:
The problem was there before, you just couldn't hear it through the restrictive filter/box setup. Also, having more air available exacerbates the problem. This can be taken care of with a "Wicked Wheel" a new compressor wheel that lets the pressure bleed back over it without stalling as bad and making the noise you are referring too. See if the sound occurs louder when you are heavier on the throttle--it will probably be the most noticable at gear shifts.
If it is indeed gone and you don't hear it louder at open throttle or gear shifts, definitely the EBPV. Your mileage is sucking because of the cold.
Mine went to ***** after winter hit.
Since you said it was only on a cold motor I would guess it is the EBPV. If it is, just gut the damn thing and be done with it.
The other possibility (slim chance)
Turbo stall:
The problem was there before, you just couldn't hear it through the restrictive filter/box setup. Also, having more air available exacerbates the problem. This can be taken care of with a "Wicked Wheel" a new compressor wheel that lets the pressure bleed back over it without stalling as bad and making the noise you are referring too. See if the sound occurs louder when you are heavier on the throttle--it will probably be the most noticable at gear shifts.
If it is indeed gone and you don't hear it louder at open throttle or gear shifts, definitely the EBPV. Your mileage is sucking because of the cold.
Mine went to ***** after winter hit.
