i had a few people tell me my car has a barometric pressure sensor. the thing is. none of my diagrams show one and i cant find it under the hood. i know someone said its a blue connector. BUT i do have a MAP sensor and it has the vacum hose attached. i am wondering if this is a vacuum sensor like it says on the diagrams and there is no baro sensor needed for my car. i have an 83 z28 with a 5.0 4-bbl

ok. so i answered my own question. after finding out what wire coming from the ecm connector was for a baro sensor on a diagram, i checked the connector on my car and there was no wire that went to it. so no baro sensor.

 

the baro sensor looks just like a MAP sensor and I believe they were all mounted on the firewall right by the a/c evaporator core housing. I think the 84 5.0 h.o was the first to use it but maybe the 83 h.o had it as well. I don't think the 82-83 LG-4's had it.

 

From what I understand, there is not supposed to be anything connected to it because it needs to sense the relative pressure to the vehicle.

 

so whats the point if nothings connected to it?

 

It measures atmospheric pressure, so it doesn't need any hoses connected to it.

 

oh, is there wiring to it though i assume?

 

There is wiring.

When there's no dedicated BARO sensor, the ECM usually calibrates atmospheric pressure from the MAP before the engine starts, or at WOT when the manifold vacuum is zero.

 

That's what I was trying to explain but couldn't find the right words lol!