The whistling was happening even before the filter was changed when the car was driven for a longer period of time and starting the next day after sitting overnight. As far as I recall, it started happening when the hot weather set in and even early morning temps here are above 90 F. Filter was changed because the filter line had ruptured while driving as explained in my original post.
The noise comes when fuel pump primes, KOEO, and then starts again when engine is running. The noise does not change with speed but goes away after driving for a few minutes. It used to be that noise went away after starting and idling for a minute or so, or by the time I would pull out of driveway. It has gotten worse and now it goes away after driving a few miles.
I am not sure what metal line you are describing, I do not see any metal line near fuel pump, filter, on top of tank. From fuel filter, a plastic line runs along the entire length of fuel tank and connects to a metal line through quick connect fitting and that metal line then goes to fuel rail. I have checked fuel pressure at schrader vale near fuel rail and its 60 psi within FSM spec of 58 +/-5. Fuel regulator is part of fuel pump so there is not a question of having higher pressure before fuel rail.
Because of the fuel filter line rupture, I was thinking there was pressure build up in the fuel tank and may be there was a problem with venting and whistling noise was pressure escaping from seals. So using vacuum gauge I checked a vent valve that goes to leak detection pump from front vapor canister and it is working fine. The purge valve in the engine compartment is also good. Could it be the two rollover valves on top of tank and how do I check if they are not blocked. Is there a way to check tank pressure?
P.S. With KOEO, I just listened to noise using stethoscope by placing the prob on fuel filter, and supply and return ports on top of fuel pump. The noise is more audible when prob is on on the supply port of fuel pump.
Sunday, August 13th, 2017 AT 11:05 AM
