Hello, i just finished my build and i started up the engine and it idles but is very rich(blows black smoke) and then i noticed that my map sensor is not working correctly when i was logging. Was reading 96 kpa all the time and didn't change not even when revving. Unplugged it and read 0 kpa. I have already tried like 4 map sensor and they do all the same. It is an 05 Silverado SS with an LQ9 and LS3 heads and custom 226/232 cam. I also have an L92 intake on it and because they have the map sensor up front i had to extend the wires a bit but i already checked those and they seem to be fine. Anyone, please.

 

Is this a 1 bar MAP sensor? When you extended the wires did you get them hooked up properly? 1 will be 5v reference, 1 will be ground, and 1 will be voltage out to determine the pressure. Is the tune scaled properly for the sensor that is in it?

Turn the truck KOEO (Key On Engine Off), and apply vacuum and pressure to the sensor to see if it is working. If it is not working it sounds like it is something with the wiring from extending it.

 

Yes i checked and everything is fine with the wires.Map sensor is actually working fine. I replaced the ecm and everything seems to working good. Maybe it was burned or something.

 

Later found that one of my pin on the ecm was bent so it did not have contact with the wire. Fixed that and it works again.

 

Good to hear. Glad you figured it out.

 

Thank you man!