need help identifying a major problem. it started last nite as a was driving my car my boot got stuck between the clutch and the floor mat while the clutch was pushed down, and when i was able to get boot unstuck i released the clutch pedal too fast causing the car to jerk hard and the check engine soon light came on and the car started to stall when i pushed on the gas pedal and the and the rpms would barely move up. i pulled over to see what could be the problem and at idle while in neutral my car would stay reved at 1500 rpms. when i pushed the gas at idle the rpms would move up very slowly to about 4 thousand rpms and the car would backfire horribly and the rpms started to bounce, with lots of black smoke comming out of the exhaust. the car is still drivable and the turbo spools but the rpms move slower that ever and backfires alot. i hooked the car to a ODBII and got the code P0102 MAF or VAF circuit low imput but i'm not too sure what that means. does it mean that my mass airflow sensor is not reading correctly due to its circuit being burned out? if so where is it located so i put in a new circuit. any help will be much apreciated.

 

Need a little more info, what mods do you have?

 

mods are intake, greddy intercooler w/ lower piping, turboback exhaust w/ no cat, boost controller, act clutch w/ fidanza flywheel, safc-II but i didnt have it set with and fuel alterations. i also have an aem wideband and after this started to happen at idle it would read at it the 13's air fuel ratio and when i was driving the car the back home it would read super rich with the air fuel ratio reading far below 11 to 1 under any aceleration even when i barely pushed the gas pedal. also i went back and edited my first post since right before my boot got stuck when i was shifting gears and when i got my boot loose i released the cluch too fast causing the car the jerk hard.

 

Check your connection to the S-AFC or the connector on the MAF sensor.. Seems like the sudden harsh movement knocked a connection loose.. Yeah, sounds like the MAF sensor is reading incorrectly and "limping home"

 

Sounds like your MAF took the hit. What kind of intake do you have? Is it mounted securely and not just flailing around hitting everything while the motor shifts changing gears?

If you Know a friend with an EVO, try swapping MAF's and see if it fixes it. Re-set the ECU when swapping MAF so it won't store the code that's in it.

 

I'm 100% positive it is your MAF. Same exact thing happened to my friends 240sx. To test this all you have to do is unplug the MAF. When you do this the idle will not smoke or backfire, but it will smoke and back fire even more as you move up in rpms. When this happens you know you need to change the MAF. A quick fix to keep it driveable for now is to adjust the throttle body so idle is at a high 1500-2000 rpms.