Nissan Repair: Nissan Primera 1997 - Acceleration Hesitation, fuel pressure regulator, acceleration problems

Question
Hi
I am driving a 1997 Nissan Primera 1595 cc manual car for the last 3 days and have noticed some severe engine acceleration problems.
The car has been parked up for at least three months prior to my use and the previous driver has confirmed that he has also had similar experiences before the car stood idle.
The car was flat and has had a new battery fitted.  At engine idle the revs seem fine with no fluctuation.  In light/gentle acceleration through the gears the car also seems to operate as it is expected to run.  Only when hard/heavy acceleration takes place will the following symptoms occur:
Strong hesitation – the same feeling as though you are running out of fuel and the rev counter dramatically drops back, with no power getting to the wheels.  This can be a danger when trying to overtake a car in motorway or duel carriageway manoeuvres.
This can happen in any of the gears but fifth gear seems to be least problematic.
This hesitation or stumble seems not to follow a fixed cycle in that if I hard accelerate tem times it will not take place on every occasion, the colder the engine the more frequent the occurrence.
I am about to check and clean the plugs but I am no car enthusiast and any common sense advice you can give and / or resource suggestions will be most welcome.

Answer
Martin,

I will assume you have the petrol version?  If so, check the spark plugs to make sure they are fresh.  Check the fuel pressure to make sure it is within specification.  A dirty filter or a stuck fuel pressure regulator will cause the problem you describe.  If the problem is intermittent as you describe it might just be an indication of a lean out condition since when cold the car runs rich and that seems to overcome the hesitation you describe.  So, a tuneup is in order as well as a check of the fuel pressure.