Long story short. I have a 2 liter b18c5 and i got a basemap for it on a s300 that i was using. I changed my bad thermostat and car was running fine for a day, then all all of sudden got CEL code 11 for overheat. Car running fine tho and not overheating. ECU not mounted ATM doing some work, so driving hit a bump ecu moves around, then CEL comes on. Turn car off then on, CEL disappears.

It is not a constant CEL it comes and goes as it wants.

3 questions.

1. Is it possible a connection is loose in my ECU causing it to go crazy and did i blow my ECU? Car runs fine hits vtec and everything, no crazy idling nothing just this annoying CEL keeps coming on lol

2. When i use my OBD 2 itr ecu, does the computer adjust the air intake and fuel intake?

3. My s300 is it messed up or is it the basemap that i got on it

 

Reset the ECU and see if it pops up again.

 

I did it goes away but comes back every so often. Used the stock ECU no CEL


Bummmpp

 

If the connection was loose or something, like the plugs weren't fully in the ECU, then you might have a fuel cut-off at a random RPM but you can always check if it's fully connected. If you're talking about an OEM P74 ECU, it will not adjust to the Air/fuel on it's own because the engine is a 2.0L like you are saying, they are meant for 1.8L so if you tried to run it like that it would have a bad VTEC engagement because it is running lean. You might want to check with your tuner on the S300 unless you did it yourself.