Bucking (abrupt, total power loss) on heavy throttle, stalling.

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2003 MSP
Bucking (abrupt, total power loss) on heavy throttle, stalling. It is so bad it jerks the car and I instinctively push in the clutch.

Stock '03 MSP. Was doing it before I replaced Maf (I got Lean bank one error. changed MAF, disco'd battery to clear engine light.) Changed MAF. Does it when hot. Then it won't idle for a minute.
Plugs 26,000 miles old. all other service up to date . 117000 miles.
 
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Probably need to make sure that all of your throttlebody and intake/charge piping connections are tight. Also look at the blow off valve pipe and make sure that its not broken where it connects back to the charge pipe.
 
You might also do a fuel pressure test. Mine is doing this. I never considered the maf being the cause but i might swap it with my spare to check. Getting the same code for bank 1 too lean and lean bogging under load.
I have changed plugs and coils recently and primary o2 sensor. Secondary o2 will be changed this week and im doing the fuel pump and filter just cause they cheap and easy.
But check fuel pressure if you or a buddy have the tool.
 
Its totally stock. I imagine its 5 PSI. Last night after a 7 mile freeway drive, just taking it easy, it began stalling when I exited and hit a stoplight. I had to rev it to keep it running. That's the worst its been. I checked all the obvious stuff. Haven't looked at the plugs yet but they have close to 30,000 on them.
 
I was having the same problem. When checked by a buddy of mine, several codes popped up. Changed the coil packs, spark plugs, the wires, and it got full power back again.
My other problems now, is when I hit it hard, it starts begins to choke a little. I'm considering changing the fuel pump. And the car is over heating. I changed the thermostat (fail safe), the coolant temperature sensor but still having same problem of overheating.
 
The fan question was a response to the post above my last. Coilpacks are a common part to fail on these cars, glad you figured it out.
 
New coils in. Runs but still stumbling when floored. I'm not sure what to look at-Might have to take it to a mechanic.
 
Didn't change the plugs or wires. Its such an abrupt loss of power it really seems like it wouldn't be caused by something bigger than that. I could be wrong.... almost feels like total fuel/spark cut. I'm not a mechanic however.
 
It sounds to me like fuel cut but that would typically only be if you are running more than 10psi or so or if it was really cold (30s or below). Have you cleaned the MAF or tried another MAF sensor? I would try new wires first or maybe swap the replacement coils for some others, sometimes parts stores will let you try that. It would be worth replacing the spark plugs as well, and be sure to gap them to .028".
 
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