Hi, I have a 98 LS 4x4 4 dr blazer, 4.3L vortec, and when i press the accelorator down, around halfway, the engine will fall flat on its face, it wont get above 2000 rpm, but then it will clear up when i let off of it. a check engine light appears at 3500 rpm, so i got the code read at autozone, it came up as PO101, a faulty MAP or MAF sensor. any suggestions as to what i should do? should i replace map sensor first??? thanks so much

 

P0101 - Mass Air Flow Sensor Performance

Clean your MAF sensor, but run a search first for a walk-thru on doing this as you can screw up your MAF and they aren't cheap.

Also make sure that the crankcase vent line is hooked up to the back of the intake ductwork above the throttlebody.

 

not for nothing but also check o2 sensors and make sure there functioning properly because my 96 lt 4.3liter 4dr 4x4 is doing somthing simaler and took it to advanced auto hooked it up to diagnostics and codes coming back are for the o2 sensors just a thought! if u cant figuer out the problem by changing the map or maf