Chevy Monte Carlo Blower Still Runs- Engine Flashing P0300

Question:
2005 Chevy Monte Carlo. After stopping and shutting off the engine, removing the key, why does my blower fan motor still run? Start and stop the engine, remove the key, still runs. Took the blower fuse out of the fuse panel by the passenger side door and it still runs. We took out the main 30 amp fuse under the hood that says blower motor and it stops the fan.

Answer:
By what you are describing this sounds like the blower control module / resistor is shorted, or the a/c control head is malfunctioning. The blower control module is the most likely cause since pulling the 30 amp fuse takes all power from the module. The way to be sure is to disconnect the blower module and test for a speed signal coming from a/c control head. There should be no signal with key off. Unplugging the a/c control head during this malfunction will also tell you if the control head is at fault.

The blower control module receives signals from a/c control head and power from that 30 amp fuse so disconnecting it takes both out of the system. The blower control module is under the passenger side dash in front of the blower motor. If would like to make a donation/tip and come back I will help with step by step diagnosis of this system with a schematic.


Question:
1999 chevy Monte Carlo. My engine light pops back on after my Emissions check. My heater does not work and when I got blower speed on 0 I hear a noise. Then when I put it on position 1 it stop. So what do i do?

Answer:
OK, so i think i can understand what you are saying. There is a noise in the blower motor? Then there is probably leaves or paper in it. Very common problem. Remove the blower motor and clean it out. If there is nothing in it, then replace the motor and inspect the plastic cage for having damaged fins.

Question:
Problem with my 1997 Chevy Monte carlo LS:
Check engine lights flash codes p0300. Changed all sparks plugs and wires.
Question = Why does my check engine light have this code p0300. We replaced coils and spark plug wires.

Answer:
First you need to find out which cylinder(s) is misfiring. If the spark plugs and wires were replaced, another common cause for misfiring is a burned / corroded ignition coil. That should have been obvious while replacing the plug wires. Another common cause for P0300 on this engine is a sticking injector or rocker arm problem. Have a fuel injector drop test done to see if one is sticking.

If you hear an engine tick on the top end, remove the valve covers and look for a loose rocker arm bolt. This is a common problem on the 3.1L and 3.4L engine. You would need to have the threads repaired and the arm tightened back down.


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