Mazda Repair Questions? Ask Mechanics for Answers ASAP
Good morning Robert and happy new year! The heat will work fine without the compressor clutch being plugged in. I would unplug the clutch and see how it does then.
It does sound like the compressor may be going bad and putting a heavy load on the engine causing the problem here.
Let me know how it goes and we can work further if needed.
Help me understand what's going on so I can help you diagnose the issue; the way I first understood, it seemed that you said the engine missed/stumbled only when the A/C compressor was engaged. Can you remove the blower fuse and tell me if the stumblking goes away?
Since you state "The engine stumbles/misses when the heater blower switch is turned to position 1,2,3 or 4." The logical thing to do would be to remove the fuse to confirm the blower circuit is where the problem lies that is causing the stumble. Once we knew that for a fact, we could then reinstall the fuse and proceed to check each of the components connected to that circuit (blower motor, resistor, switch) until the culprit was found - which would best be accomplished by mesuring voltage drop on each.
I'm a retired Master Tech and Technician Instructor, but if you feel the advice I'm giving you is wrong just let me know and I'll opt out of the question. Otherwise, we can work togrether and get your problem solved. Your choice.
Thank you, ***** ***** me a few minutes to l0ok up the diagram and formulate the diagnosis. Be back in a few...
Hey Tito. After studying the diagram, I've come to the conclusion that the only thing that could be pulling that much current and still not cause the 40 amp fuse to blow, would be the blower resistor. So, to confirm, with the ignition off, turn the fan switch to position 4 (MAX) so ground is applied directly to the motor without going through the resistor; then start the engine. If there is no stumble, the resistor is bad and needs to be replaced. To do so, you'll need to remove the glove box to gain access to the blower motor housing. Once the glove box is out of the way, you'll see the resistor fastened to the housing by two Phillips screws. Unplug the resistor and remove the two screws, then pull the resistor out of the housing.
Autozone lists the resistor as Duralast part number JA1169.
Thank you for sharing the good news. Looking forward to hearing from you soon.