I am at a loss and figure I should see if anyone else has had this issue. 93 Honda Civic DX. Converted to a 5spd manual. I just replaced the MAP sensor and it didn’t solve anything. If I unplug the MAP sensor vacuum line and plug it the idle slows down and regulates.

Have any of you dealt with this before?

 

There have been a couple threads troubleshooting surging idle problems recently. Read through this one and search for the others: https://honda-tech.com/forums/honda-.../#post52087035

Hope that helps...

 

The MAP sensor is bad. Replace it.

 

I don’t have a vacuum leak from what I can tell. I tested it with starter fluid.

 

Remove MAP sensor and inspect. Your own test result points to the MAP sensor.

 

I tested the MAP sensor and all I am getting is 2.26volts. Clearly my MAP sensor is the issue. I’m wondering if the previous owner installed the wrong MAP sensor. Does anyone have a part number for a factory MAP sensor. The local parts store quoted me $280 and $330 for the sensors

 

Enter your VIN at site below and look up MAP sensor part number.

https://www.bernardiparts.com/

 

Is there something unique about the DX model? It has a different MAP sensor part number than other models and it is considerably more expensive.

 

Is it firewall mounted ?

If so you can use one that was mounted to the throttle body.

I did this on my JDM B16a and have not had any issues, just grab one from the junk yard and try it, just about any obd1 or 2 should work if the plug is the same