MAP sensor

[speedrider1]

Code P0401. 1998 Camry 2.2 engine. I tested EGR valve as follows. Put vacuum on it while running and as soon as I apply vacuum, it runs rough and stalls, and it holds the vacuum indefinitely. I also pulled EGR off and cleaned it before that test. It looked pretty clean to start with. I did not pull intake manifold off to clean. Would this be necessary? I tested VSV valve off of the car. Very hard to get to, but I got it off. Air can be blown thru port e to g. Added 12 volts and now air blows thru port e to filter. Ohms checks 39.4 at about 58 degrees. Book says Ohms 33 to 39 at 68 degrees. No continuity between contacts and body of VSV.
Checked Map sensor. It checks voltage from PCM at 4.97 volts between pin 1 and 3. Book says 4.5 - 5.5 volts. I back-probed pin 1 and 2 and voltage checks 1.5 volts with 3 in HG vacuum, and goes to 3.2 volts at 18 in HG. My repair manual says voltage should be 1/3 to 1/2 volt at 3 in HG and go to 2.1 volts at 19.7 in HG, so does that mean Map sensor is bad (out of spec)? Would that voltage variation cause P0401 code?
Thanks

[speedrider1]

C'mon, no one?? How do I determine what to replace, or do to get my check engine light off. I know the saying, "I would run out of money, before I run out of parts to replace." So I don't want to just throw parts at it.

[Pvt-Public]

Just a thought, but have you searched the forum for P0401? I just did and just in the first 2 pages there are about 20 discussions on this. I would start there. Are you also having problems with the MAP?

[speedrider1]

Originally Posted by Pvt-Public

Just a thought, but have you searched the forum for P0401? I just did and just in the first 2 pages there are about 20 discussions on this. I would start there. Are you also having problems with the MAP?

I read all of them. I only saw one person mentioning testing their MAP sensor and all they said was "it checked within specs".
Mine checks voltage from PCM at 4.97 volts between pin 1 and 3. This is within specs as book says 4.5 - 5.5 volts is normal.
I back-probed pin 1 and 2 and voltage checks 1.5 volts with 3 in HG vacuum, and goes to 3.2 volts at 18 in HG. My repair manual says voltage should be .3 to .5 volts at 3 in HG and go to 2.1 volts at 19.7 in HG, so is this out of spec?
At 200 bucks for a new Map, I would like to be sure this is a problem before replacing.