Go back to the list of possible causes.They talk about the MAP sensor. Mazda has its own name for it: EGR Boost Sensor. I am sure this name was chosen by an intern with the help of a Japanese-English Dictionary. Nothing gets boosted here.
In the 98 protege there is a vacuum line going from that EGR Boost Sensor (firewall passenger side) back down to the intake manifold. I pulled the hose of the nipple there and poked into the nipple with a 3" piece of wire. I felt resistance and poked through. It is a place for deposits to form and thus mess with the vacuum signal to the EGR Boost Sensor.

 

ok, since it is circuit problem, these.
1) do you have access to a digital volt meter? If so, piggy back the leads into the electrical connection on the maf, read voltage, and post it.
2) Did you replace the maf? I read where you cleaned it. Did you also use electrical cleaner (not maf cleaner) on the electrical connection?
3) Did the cel come on after 5-6 starts, or after mileage?
4) Has there been any change to the air inlet/intake duct?

 

1) I have and will post voltage read.
2) yes replaced maf. No used maf cleaner.
3) 4 starts on 2 trips approx 35 miles.
4) no change to duct.

 

Went to look for this EGR Sensor today,found it and one of the vacuum pipes had 1/2 inch of pipe on the plastic nipple and the rest of the pipe just lying down where it had perished. It was to short to join back onto the nipple so as a temporary fix I went in and cut 4 inches of air pipe from my aquarium pump

 

Ha!
Buy 15ft of vacuum line off the reel and replace all the lines of that diameter. That makes it both a fix of this problem and prevention of a few future ones for about $5.00.

 

This perished vacuum pipe must have been the cause of the engine check light being ON
Have now run the car for 2 days with NO light on. Replaced (aquarium) temp. pipe with new silicone air line.
Have piece of mind now knowing I also have replaced a new MAF sensor and new air filter element

 

Great! your engine has been running under less than ideal conditions some time, and it is 10 years old. It has likely built up some deposits. I would treat it to an internal cleaning with lacquer thinner (not paint thinner!)
When your tank is 1/2 full add 1 gallon of Lacquer Thinner (again: NOT PAINT THINNER) and drive for about 100 miles. Do a few nice accelerations but keep the rpms below 5000, then fill up.