code 13 question

when doing the key trick on my 91 i get a code13. while i believe this to be related to the map sensor, does that mean i need to replace the map sensor or is it something that is attached to the sensor. i do have the newer intake with throttle body spacer. any ideas thank you in advance buster.

13 Slow change in Idle MAP signal No variation in MAP sensor signal detected. CEL:Yes

13 No change in MAP from "Start" to "Run" No difference is recognized between the engine MAP reading and barometric pressure reading at engine startup. CEL:Yes

You have to remember that the ECU/PCM, as far as computers go, is brain dead. It simply expects a range of input from each of the sensors, and if a sensor's input is out of the range expected then a code pops up. The code is an indicator of nothing else than the ECU/PCM is not finding what it expected too. Finding out why is the job of the person working on the vehicle, i.e., if you went and bought a MAP sensor and slapped it on, it is a crap shoot if the code will go away. The problem could be something else causing the MAP to give an out of spec reading, or there could be a wiring problem, or even the ECU/PCM is faulty.

This is when an FSM for your vehicle is essential. Test your way to the solution.