Hello fellow Brickboarders! I have had this problem for a couple of months, but have not yet posted since I wanted to tackle it first... These are the symptoms; please feel free to ask for more info as needed.

Car is a 1993 Volvo 944 Turbo. It has 63k miles and almost suddenly it has lost its acceleration and driving it is very unpleasant now:

During city driving, the car will sometimes not respond to the gas pedal (huge hesitation), you have to let it go and then hit the gas again for that car to accelerate. Car has to be driven with the gas pedal pressed further down than usual, hence at lower gears, because it feels like hauling a trailer full of rocks. If you release the gas pedal abruptly, the car will usually stall, or idle at less than 100 rpm with the CEL on, until you slightly press the gas again; then idle comes back to normal and CEL turns off.

If I drive the car in the highway, it takes forever to get to highway speed, and almost impossible to go past 60mph. If I kick down to overpass, the car will go to 2nd gear and RPMs climb rapidly, however I get poor acceleration. If I give it WOT, I get very brief “waves” of acceleration, followed by a feeling of being glued to the road. Since I purchased this car a year ago, I’ve never seen the turbo needle go deep into the white area (climbs a bit past 12) but the car used to respond very well.

Car is easy to start, in the morning and after being driven, and idles smoothly. No visible smoke is coming out the back. Only code states that there is no signal from the AMM’s hot wire. Initially I though the cat had clogged up, but it checked out OK. In fact, I drove the car without anything connected past the headers (really loud) and still got no response from the car. Compression was tested and all cylinders are over 130psi. Sparks came out clean. Throttle body has been meticulously cleaned. TPS and IAC appear to be working fine. Injectors where also cleaned and aren’t stuck. AT is shifting properly, and the torque converter passed the stall test. Any ideas!?!?!?!?!?!?
I am desperate. As usual, any input is highly appreciated!

Regards;
JGCBAIZ.