350z revs hesitation and idling problem

[Lotar83]

Hi everyone, I need some serious help.I have a 2004 Nissan 350z,been battling with this problem for months now! The car randomly, if engine is cold or hot no matter, battles to idle,and there is an hesitation throughout the rev range ,but only sometimes.

We look at all of those air fuel mixture issues,we cleaned the maf, reset throttle, checked for vacuum leeks, reset ecu, spark plugs,plug wires, but nothing.

Then I find out that could have been the crank shaft sensor,keep in mind no faults on dash,when we opened up the sensor was full of metal filing from the release clutch bearing,cleaned put it back then the fault appierd on the dash,slip light,engine light and vdc light came on. Replaced bearing, replaced crank shaft sensor,no metal filing anymore,sensor is clean. Start the car drove it for about 10 km started again with idling issues and hesitation.rechecked the sensor to see if it got dirty,but was clean, drove it again few kilometers seems was good then again same issue.

The funny things is the slower I drive the worse it becomes,if I approach a circle or a drive way and turn in the car would just die, or start idling weird,like if there is no spark or no fuel,but then suddenly will be fine again.

The car was fitted with a software upgrade long time ago,and maybe that it can be the fault?,ecu problem? But the problem should be there constantly if ecu problem?.

Running out of ideas guys. Don't know what else to do.

[Lotar83]

By the way the car is just been serviced,with new spark plugs,oil, etc....the usual service

[30 ounce]

Sounds like a dying fuel pump.

[Lotar83]

drove the car today and indeed I feel lots of hesitation wen turning on the right,but less on the left,on the straight it's okay,on very slow turns car would just die as well. so reckon the fuel pump is packing up?