I have an issue with either the computer or the MAP Sensor. The other day I was headed home and my car was surging when I reached 40 mph. I have had a check engine light on. The last time I had it checked. They told me it may have been a dirty Mass air flow sensor. I was able to make it back home and run some diagnostics on the car. When I started up the vehicle it idled ok but when I age it some gas up to 3000 RPMS the vehicle started surging. I cut off the engine and researched the issue on the internet. It was suggested that the MAP sensor may be bad.


They also mentioned one of the lines on the MAP sensor went back to the vehicle computer and it was suppose to run about 5 volts. It also said to hook up a manual vacuum pump up to the MAP Sensor When I checked it read at 13 volts with out touching the manual vacuum pump. Now I can not even get the car to idle. Any ideas on what my issue might be outside of the vehicle computer?


As a secondary note: This same vehicle has also experienced issues of cutting off while driving. The Dash lights and gauges have gone dead. I was able to restart the car and everything kicked back on. I also know that I need to replace the Alternator. If needed I can repost this on another thread after I correct the problem above.

 

First, which wire are you checking when you get 13 volts? Next, disconnect the MAP sensor electrical connector, and then start the car...does it run better?

 

I checked the wire that was going back to the ECU. I know the other two wires are Ground and Positive. I had disconnected the MAP sensor and there was no change in how the car ran. Now it will only turn over and will not stay running. After doing more research I have narrowed my problems described above to my ECU going out causing my vehicle to surge and the gauges going off and on. I traced my problem down to my ECU 37820P0JL63.

Is there a way I can test this ECU to see if this is the problem?