So i recently switched my A/C for a heater box and it started throwing a code 34. I looked it up in my manual and it says it's the MAP sensor. So i looked it up and the drawing for the MAP plug looks like the blue plug that is unplugged. The only problem is i cannot for the life of me find out where to plug it into. does anyone have a pic to help me out? here's a pic of everything and it's a '84 305 Carb.

 

MAP sensor is usually attached to the very top of the firewall lip where the hood meets the lip - just above the heater box. Do a part lookup at autozone.com for a pic.

 

that's weird because i've never removed it yet i've passed all of my smog tests before. it just recently started throwing the code. does anyone think it could the SES light could be caused by something else?

 

also, when i was at the j/y i noticed that all the cars that had a MAP sensor the plug was green, but mine is blue. should i just grab a sensor next time i'm out and plug it in?

 

The MAP sensor IS NOT by the heater core. The MAP sensor is between the brake booster and the fender.

The sensor on the windshield cowl lip by the heater is the barometric pressure sensor. It looks just like a MAP sensor, but it isn't. No vacuum line gets hooked to it. Not all cars have it. When it's equipped, the ECM can use its indication to tell the difference between the presure in the manifold and atmospheric pressure, thereby allowing it to take changes in atmospheric pressure into account in determining fuel and timing needs, instead of having ONLY the single input of manifold absolute pressure, which does not allow it to adjust for things like, say, high altitude.

The MAP sensor plug is always black. The baro sensor plug AFAIK is always green. But you know how that sort of thing is. However, both of those have a plug with the flat spade terminals, not round Weatherpak ones. Therefore that isn't what that plug is. Cannot be. Maybe if I knew what color the wires are, it would help identify it, but I won't guarantee that.

As hacked up as that car is in that area (it has A/C wiring plain as day, including the plug for a low-pressure cutoff switch, but a non-A/C heater box) there's no telling what somebody stuck in there at some point in its life.

If the car passes inspection, don't worry about it.

Did somebody hack your account and change your avatar? Do you know what it is?

 

haha, nobody hacked it i just love that pic. it's on my facebook as well lol.

i was the one who took out all the A/C stuff and put in the heater box. I thought that was the reason it is throwing a code 34 (that thing being unplugged) but i guess it was just coincidental timing. It won't pass inspection if it throws the code while it is on the machine. oh well, guess i'll just have to let whoever buys it worry about it.

 

Pic from my '85 showing the where your plug connects to the BARO sensor-just to the right of the evaporator (was swapping the AC compressor when the photo was taken, so excuse the work in-progress).



The CCC systems referred to the MAP as a VAC sensor. You won't find reference to a MAP in most manuals, just FYI...

 

In my '87 (must have been doing something to that one that day too as the rad cap is off):