HIGH IDLE AND MASS AIR FLOW CODE AFTER INTAKE JOB. 3.4 V6
1999 Pontiac Grand Am
March, 26, 2012 AT 7:13 PM
I did a lower intake gasket, thermostat, and tune up on the car, had a rough, high idle and pulled a mass air flow code, checked for a vac leak and found one, fixed it, and cleaned up the idle. Although it still idles around 1800 and has a mass air flow code, I also swapped the Maf with a good used one with no difference, also makes no difference if the Maf is plugged in or not, if the map is unplugged it shuts down immediately, I am lost and cannot find another cause for this, idle air control valve also seems to function fine as well as the tps and it also has a brand new battery and pcv valve
First, make sure the big hose from the aircleaner to the throttle body is on correctly and there are no leaks. That will trigger the mass air flow code.
If the idle was correct before the job, then look at the connection for the iac valve. Otherwise, it may be carboned up or failed.