Lack Of Power When Engine Hot

[Gee]

I have had a 2.0 glx 1996 Gal for 7 months now, with various problems since i bought it. The latest of which is that when the engine has warmed up (after 4 or 5 minutes) the acceleration is very poor. It seems to come in 2 second waves with a restrictive feeling after every wave. if pedal not depressed very far it will accelerate smoothly, all be it slowly. There is also a noise coming from the vicinty of the middle of the rear engine bulkhead (poss area of rear of cylinder head) when the accelerator is depressed and the car is in gear (no noise when accelerate in neutral). the noise almost sounds like a diesel engine type noise. Could this be related to the Acceleration problem???

 

So far i have changed...Plugs, Plug leads, Cat, Fuel filter, Air filter. Coils checked. : I have also checked the MAF by fitting a known working one for diagnosis, didn't make any difference. Air intake sensor was also checked for resistance and voltage against temp, no probs there either. I have felt around the back of the engine, when running, but can't feel any air leaks..

 

Any suggetstions???