A while back, I copied a diagram off of www.fordfuelinjection.com (which by the way is shut down now by FORD's Lawyers for copyright infringement of protected material supposedly). Anyway, the wiring diagram was specifically labelled for 86-93 Mustangs and showed a relay titled MA/O2 Relay. It showed the left and right O2 sensor and the MAF sensor wired through it ... does such a relay exist and where is it??? The diagram also shows an ignition relay ... does it exist and where is it??? Diagram also shows the Fp Relay and EEC relay and I am familiar with them. Since i am having O2 problems checking the so-called MA/O2 Relay would be important I would think? And, after 20 years, the so-called ignition relay should also be checked and/or replaced ... so knowing where these relays are would be most helpful!!!