Or so i think its an issue with the MAP sensor.

Long story short, i have a 5.3 LM7 in my 85 10. I got it running (kinda). Some times is starts up and i can keep it alive by messing with the throttle. Then when Hot idle starts (open loop), it will idle, but bog down under throttle.

In HP tuners, it says my MAP is reading 1.5bar all the time under all conditions. Im using a china swap harness. I verified the pin outs match the wiring to the map sensor pig tail.

I tested the sensor and pig tail with a volt meter. With the connector tab facing up, I have ground on the left (connector A i think), 5v on the right, and 12V IN THE MIDDLE?

Isnt the middle supposed to be a signal wire? I verified the tune is set up for use of a 1 bar map, which is what im using. I also changed to a new map sensor with no change.

I should also mention im running a summit v2 ghost cam. 222/236 lift i think. 115lsa. .600/.575 lift at .50 i think

 

Did you tune it after the cam install?? If not, you better tune it before doing anything else.

 

If you have 12v on any 5v sensor circuit, that's your problem.

You should have a 5v wire, a ground(reference wire) and a wire that goes back to the PCM telling the PCM what the sensor voltage is

China parts strike again.