Codes P1400, P0120, P0105 issues.

[gho5tone]

So I've been getting this code in series for awhile now and each time I thought I solved it, it keeps coming back.

I have tried swapping MAFs, ECUs, and MAP sensor. I'm starting to think it might be a wire issue of some sort.

While researching for answers I came upon a thread from 2004 that stated pin 81 of ECU provides 5v to sensors and the OP of the thread solved his problem by splicing wire 81 to all three of sensors at the harness and apparently that solved his issue.

My question is should I do this splice, or should I work resolving it another way.

 

[gho5tone]

Finally got around to working on my car and to my surprise Pin 81 is not getting the reference 5v. That would explain why the sensors would throw codes.

Now how do I go along and solve this?

 

[Dsmkauai]

Check grounds that tie into that pin, find the other end and see if you have power there.

 

[gho5tone]

Turns out it was a loose connection to ecu causing my MAF and TPS to throw codes.