Code 12 (MAFS) Need help! Matt? Jeff?
Code 12 (MAFS) Need help! Matt? Jeff?
I was driving my car the other day, and it started running like crap. It barely ran. I had to use very partial throttle, and couldnt get high in the rpms at all. I checked my codes when I got home, and got code 12, which is the MAFS code. I checked all connections, and all were fine. At idle, vacuum would steadily drop from 20 to 15 in hg, then revs would go up and bring the vacuum back up. I disconnected the s-afc, and the vacuum problem went away, but still couldnt drive it, cause it ran the same way.
Next thing I did was disconnect the MAF all together. Car runs fine in "limp mode" until the 2400 rpm limiter is reached. I followed the FSM procedure fully twice for the code 12, and tried another MAFS, but of course it didnt make a difference (shouldnt have since the procedure went ok).
That made me think that the connections in the ecu harness were bad, so I checked them too, but they came out fine too.
Anyone have any suggestions? Matt or Jeff?
Next thing I did was disconnect the MAF all together. Car runs fine in "limp mode" until the 2400 rpm limiter is reached. I followed the FSM procedure fully twice for the code 12, and tried another MAFS, but of course it didnt make a difference (shouldnt have since the procedure went ok).
That made me think that the connections in the ecu harness were bad, so I checked them too, but they came out fine too.
Anyone have any suggestions? Matt or Jeff?
Originally Posted by jim90gxe
Did you check maf cranking+idle voltage and continuity at the ecu harness? The FSM should show cranking and idle voltage.
Thats part of the fsm procedure, all voltages came out fine, and all wires had continuity
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