MAP Sensor Operation/Issue

[04DetroitLS]

Here's our symptoms, first start up the car, runs fine, after 5-10 minutes it will start to behave very badly, become EXTREMELY rich, back fire, all that crap, and doesn't resume being good again until it's shut down for a minute and restarted.

We discovered the vac line to the MAP sensor had completely failed, but not the one to the FPR.

Would the lack of a vac source to the MAP cause these problems?

Thanks.

 

[torq455]

yes. low vac to the MAP means the PCM thinks the car is at WOT, so it adds fuel. any codes?