Technical Help me figure out my acceleration problem (Stilo 1.6 2004)

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Technical Help me figure out my acceleration problem (Stilo 1.6 2004)

Razon

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After starting the car, it is very slow, barely moves, sometimes stalls completely because it doesn't respond to the throttle, like it doesn't get air or something. After a few seconds it randomly jumps from 1k-ish rpm to 4k and the car accelerates like a rocket, then it stalls again the next intersection.

Diagnostic shows no fault codes, spark plugs are brand new, cam belt replaced, throttle body cleaned, ECU repositioned, I suspect the MAP or Lambda sensor, here's a graph I recorded when I was driving around with a warm engine (the midle part is when I let it idle, around 750-800 rpm):

iptSYaS.png



This strange issue mostly happens when the engine is cold, but multiple times it stopped responding to the throttle (revs don't go up, but not down either) even with a warm engine.
 
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I may have figured it out after months without luck.

I disconnected the map sensor and the car runs better than ever, even in -8°C temperatures.

Now the question is, was the map sensor broken or is there something else going on? Should I replace it? Will I damage my car without a MAP sensor?
 
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