Hi all,

I'm having a weird problem with a MAP Sensor and I'm unable to figure it out. So here it is. When I turn the key to the ''on'' position, on the sensor check option on the Power FC, PIM shows 2.62V. When I start the car, it then shows 1.62V on idle and not even 2 seconds later the car shuts off and then PIM shows 0.00V. Then, I turn the key to off and try again, the PIM still shows 0.00V. But if I do it X number of times (no set number of times), at some point, voltage comes back to 2.62V, then the car starts again, shows 1.62V and then shuts off again showing PIM 0.00V. Any of you guys ever experienced that problem?
I tried 2 other MAP sensors with no luck. Tried another Power FC with the same result...Now, I'm leaning towards an electrical problem. If thats the case, can I just directly wire the MAP sensor to the ECU? Meaning, I would power the MAP sensor with the ignition power for the ECU, ground it on the firewall and use a new wire for the MAP sensor signal to the ECU. The reason I am asking is because the MAP sensor power input is 5V but the ECU power input is 12V. Would that fry the MAP sensor?

Thanks.

Spec.

 

I question your grounds. Clean the ones on the main EFI harness.