1990 Volvo 240 intermittent hesitation on acceleration,

[shokelah]

Once in a while my 240 wagon would have amajor hesitation on startup or acceleration. I would press the accelerator pedal and the engine would not give me any power. It would then clearup and be fine for a while. I also noticed that the idle is high at about 1500rpm and would kick down to 1000 when it is put into gear.

I have changed th plugs, the fuel filter, both fuel pumps are working according to my dealership and the fuses have been changed.