Want to thank you very much for helping us average people to figure out problems with today's complex vehicles.
I have a 2002 Mazda Protege LX with 82,300 miles, the dreaded check engine light came on. I took your advice and got the BlueDriver. It showed 2 error codes, P0171 (System Too Lean Bank 1), and P1250 (Pressure Control Regulator Solenoid Valve) not working properly.
So I took out the PCR and check the ohms and it was very high at 100 ohms. I purchased one for $16 in Amazon saving me $85. That took care of the code P1250.
But the BlueDriver is still showing P0171. Looked at the possible reasons in the BlueDriver and one of them was vacuum leak. So I remember you said that if the check engine light comes on at idle then most likely a vacuum leak.
I first started to check the Fresh Air Intake Hose where the MAP sensor is part of and found a big tear underneath the this big hose. So I removed it wrapped it around with Duct tape. Start the engine after a few seconds the check engine light went off.
I am writing this to you because 2 or 3 times in the past I had to bring it to the mechanic and always told me it is the oxygen sensor. After watching your YouTube shows I started to wonder whether sometimes It was ever the problem, the BlueDriver I just used told me all my oxygen sensors are good.
Thanks to you in educating the public you probably saved me over $600 this time.