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Fuel Mileage dropped 4-5 mpg

868 Views 2 Replies 2 Participants Last post by  JasonblkZ06
I used to get 18-20 mpg mixed highway and city driving and now get around 15-16 mpg. I am not sure what could have changed. Driving style is the same, type of driving, and air pressure in tires is the same. I have changed the fuel filter. What about boost leaks? I guess I will check that next. Any other ideas?
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First off do you have a fuel pressure gauge? Fuel pressures would help. If nothing has changed I would suggest cleaning the maf and iat sensors. Also check for boost leaks, and any form of mechanical drag. If nothing else is found it could be early warning signs that the VP44 is failing.
Yes fuel pressure gauge reads the same. I am in the process of replacing the lift pump just to get rid of it. It might be the brakes dragging as I am in need of serious brakes which is next once the lift pump is done. I will clean the IAT and maf sensors as well and report back.
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