Volvo: 1998 S70 loses power, mass air flow, fuel pump relay

Question
Hi,
I am hoping you can help me solve a problem(s).  The dealer has stated that they cannot reproduce the problem and there are no codes from the computer.

Last year the MAF (Mass Air Flow) was replaced because the car lost all power.  The dealer replaced the MAF and the car was running fine for the past 12 months.
Over the past month I have been experiencing very similar symptoms.  I have brought the car to the dealer and they have told me that the MAF is working correctly.  They were unable to reproduce the existing problems.

Here is a description of the issues:

1. When I accelerate the car will start to move and then lose all power.  It goes down to idle and the engine idles rough.
This happens for up to 30 seconds and then it will correct itself and take off.

2.  Sometimes while driving the car just loses power.  The tachometer goes down to idle.  I can depress the pedal as far as I like but there is no response.  Then, the car gets the power back and everything is great.  This will last for about 4-5 seconds.

3.  At times when I come to a stop the car stalls.

Please help!  This is driving me crazy.

Thanks in advance.

Answer
Jeff,
Very unusual that there is not a fault code. So that would lead me to checking the fuel pressure. There is not a fault code for a fuel pump relay or pump not pumping or even low pressure. So drive the car with a fuel gauge positioned where you can see it while driving and see if there is a loss of pressure when this happens.
Also check that all the connections at the battery are good and tight. Make sure that the coil wire is not near the wire harness to the MAF.