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chipper
03-01-2004, 07:46
Does anyone know if changing the Fuel Rail Pressure Sensor could affect fuel milage. Mine was chamnged & now my fuel milage has gone from 21.3 MPG down to 17.5 MPG. Does this unit require a computer calibration after installation?
or is it just a plug & go unit?
Any help would sure be appreciated as this is a significate drop.
:confused:

chipper
03-02-2004, 10:37
Doesn't anybody on this forum have any knowledge about this Fuel Pressure Rail Sensor ?

More Power
03-02-2004, 16:55
A Tech II scan tool can be used to determine the fuel rail pressure - both commanded and actual. Whether the sensor is accurate or not is another issue.

Without specialized pressure testing equipment (which the dealer is doubtful to have) there is no way to know if the sensor is accurate.

Otherwise, there is a host of other possibilities that could affect fuel economy - from one day to the next and from one week to the next. Changing fuel quality, different driving speeds, different loads, temperatures and many others.

Also, accurately measuring fuel economy is tough to do for most people, unless you're averaging several tanks of fuel and document the driving conditions for each tank.

We do know that the early pressure boxes raised fuel-rail pressure to increase power. So, I'd assume that if the pressure sensor was reading high or low, it would also produce a measureable increase/decrease in power/performance.

MP

Lone Eagle
03-02-2004, 20:28
Are you saying 21.3 was your overall average and it went to 17.5? Later! Frank

chipper
03-03-2004, 08:01
Lone Eagle'
21.3 was my unloaded 75 MPH freeway average before the sensor was changed at 36,000 miles & now my 75 MPH unloaded freeway milage is 17.5. This is average over several thousand miles.