Ever since I bought the car 2 years ago, if it's significantly hot outside or the car has been running hot, especially when facing a slight uphill incline, it idles a tad rough. Last night it got slightly rougher and actually stalled.

I did a compression test 2 weeks ago with the TR-01 and all is solid there -- 113psi avg. without the 12% for the Mazda tester equivalent. Plugs were pretty clean, cleaned them all on a wire brush. Only about 23k miles on the car.

I'm leaning towards a bad ignition; getting the BHR coils and wires in a few weeks. Other than that... mods are in the sig... any other thoughts? AC compressor has been checked and temps are not overheating (according to the stock gauge, however reliable that may be).

Any thoughts?

 

^check air filter, MAF and coils...