Coming back with another suggestion cause I own one
Be completely ABSOLUTELY positive of NO restrictions in Air filter box inlet , most importantly NO restricted "snorkel" passages to R + L throttles ( if snorkel removed you can then chk remote possibility of cloggage dripping down from both crankcase "ventilation tubes into bores
) Hey I've heard stories of mice ,roof-rats , chipmunks crawling around inside eng. comprtmts , "sniff around"
. Maybe some JAckazz (you know 'em ) shoved a rag there ,,, so they can lowball offer on your car ?
Here's the kicker - cause your talkin sellin it , and this won't cost too much ( $40-$60) TPS (throttle position sensor) is
"crunched in the ECM together with MAF (you have two MAF ,at least one good?) . TPS basically a variable resistor(a "Potentiometer" ) yet MAF is IC's on complex "board" so when CFM of Airflow from MAF doesn't Jive with the as "seen" throttle opening as reported by the TPS , and it's the TPS being bad a Code may definately show as MAF problem . Of course could be bad MAF which we figure you've eliminated , then leaves next the wiring to & from MAF or TPS to their respective downline connector destinations -chk those last. So , I'm coming back around here feeling "warm" on your 12 code you say is an MAF flag . Really shouldn't chuck the car until you have cross swapped a NEW/REPLACEMENT TPS and with BOTH your MAF's. Lastly - you don't really need the AIR-BOX sealed w/filter nor even MAF connected to AIR-BOX (MAF to snorkel yeah
) if 'n you can't be positive there's ABSOLUTELY no restrictions AFTER MAF . GT 2/23/2018