My son just bought a 2000 CX 70 ( I think that’s the model type). We took it to oreileys today to get the error codes since it wants to stall and not accelerate. P0121 code popped up....throttle position sensor. Reading the symptoms it sounds like the problem. Question is, it’s an inexpensive part but how do we replace it? Is it a hard job? Are there any instructions out there for this?