I have a 92 305 TBI and have been messing with it trying to get it to idle. I have checked the vacuum lines, spark plug wires and everything in between. In my pusuit I did find that if I disconnected the MAP sensor from the bottom of the TBI that the car smoothed right out and idled a little high but it idled. It did spit out a code for the MAP sensor which I expected because I had disconnected it. I replaced the sensor and the EGR solenoid and the EGR Valve since I was in the area of messing with all that emissions stuff. It still will only idle nicely when the MAP sensor is disconnected. Can someone please tell me what might be going on with the car.

 

A general rule of thumb, is when you disconnect a certain sensor and it runs better, then the sensor is usually the problem.

Sounds like you need a new MAP sensor, which is a bummer because they can be pricey.

 

I already replaced the MAP sensor and still the car isn't idleing correctly unless I disconnect the sensor.

 

Guess I missed that part, guess we will have to search for a schematic and start trouble shooting wires.