Hey everyone.
I have a 1995 Honda Civic EX with the d16z6 and p28 ecu. I was having a very rough idle with the car throwing fuel out the exhaust and I got a cel#5 which is a bad MAP sensor. I replaced the MAP sensor and now the car won’t start. It cranks just fine and it tries to fire up for like one second and then it dies out. i am not sure what it can be as the sensor is a new OEM replacement. Also, when I disconnect the new sensor and turn the car on without a sensor it runs fair enough but it idles rough.
i find this very strange and I have no idea what it could be

 

Check the wires on the plug, you can inspect the prongs as well inside the clip make sure its making full contact as well as the wires are not pulled ripped frayed from heat ect..

 

Hey.
i checked all my connections and everything seems to be in good shape regardless of the age. The wires are all protected and none of them seems burned or cut. The car does turn on when I unplug the MAP sensor but once I plug it in it begins to die off once again.

 

You should check the continuity/impedance from the sensor plug all the way to the ECU plug.

Also you may want to check the ECU itself to be sure all capacitors look good and nothing has blown.

 

Hey.
min not to sure how to conduct that test. Do I use a multimeter? I know that the throttle bottle is set perfect at .5v and 4.5v at full throttle in case that has anything to do with the no start. I’ll see if anything is wrong with the ecu right now but I find it very puzzling how the car starts when the MAP is disconnected but once connected it starts momentarily

 

If Capacitors blow you can get incorrect voltages on pins which could make the ECU think something is connected when not and when connected be so far out of range it can't run.

Yes you use a multi meter, and test resistance from the pin at the map plug to the pin at the ECU plug. You need to know what pin at the ecu plug correlates to the pin you are testing at the map plug.

If resistance is in the 100 ohm or higher, there typically is a problem somewhere along the line. Looking it up, 18 gauge copper wire has 6.8 ohms of resistance every 1000 feet if solid and stranded seems to be in the 4 or 5 ohm range for a 1000 feet.

 

Bump

 

Are you sure you didn't accidentally swap the MAP and TPS plugs?

You said you got a "new OEM replacement" MAP sensor - is it a Denso brand, or something else?

 

Yes, the new MAP sensor that I got is from denso and I also thought that maybe the wires got mixed up but everything was fine. I currently have two ECUs for the car and with the original ecu the car doesn’t start up but with my chipped ecu it does start up but it just runs really rich. I’m narrowing it down to the original ecu being bad and I inspected the inside and nothing seemed burned or blown. I’m going to see if I can troubleshoot a bit more tomorrow