problem on a GE, fuel related.

[87hilux7mge]

so, my freind has an 88 n/a. running on MS2, gte coil pack, ford throttle body, header, running on map. car was working great this last summer, the motor is completely rebuilt, and had no problems until recently.

he started it up, was having fuel pump problems. so he switched it for a stock fuel pump. no change, will not idle for crap, runs pig rich at low rpms, runs lean at higher rpms. also, his map sensor is logging fluctuations through out the rpm range. i thought a faulty fpr, so we swapped in a new one, no change. checked plugs, they were all black. cleaned them, no change. checked mechanical timing, no problem. electronic timing, no problems. hes pulled necessary fuel, no change. changed pulse width to the max, no change.

getting great spark quality. then we noticed something, wierd... tubes 1, 2, and 3, are normal temp when operating, no touchy. 4 and 5, cool to touch, barely warm, i can grab them at full throttle and no heat increase. 6 is warm, but not enough that i have to remove my hand. it sounds like hell when it runs, like a subaru. lopey.

hes thinking stuck valves, but im still thinking a faulty map or fpr. pushing tons of fuel at low rpms, but not ramping up as it should with rpms.

anyone have any ideas??