Last week, car seem to run fine. Out of the blue, all of a sudden the car won't rev pass ~4000rpms. Only codes pulled up were IAT and ELD, even though it ran fine the week before with those codes.

Would those cause the ECU to go limp? Also, is there anything that would cause the car to go limp but it would not throw a code for?

This is a JDM D15B VTEC(pretty much a D16Z6), OBD1 conversion, Innovate LC-1, and P28 ECU.

Also, the only spare ECU I have is a P05; could I plug that in and try to see if it would rev over 4000rpm?

 

Bump! I need some help guys.