Intermittent Stalling, Hesitation And Idle Issues & P0100 DTC

[GeeMode]

This problem is really starting to rack my brain and I cant figure it out...

My G is acting up. It starts up fine without a problem but once and a while it will stall out at a Red light. It wont stall at highway speed (thankfully) but it does hesitate and stumble when I step on the gas pedal. Also when I am sitting still the Idle will drop down to like 500rpm and sometimes the engine will stall. It doesn't happen all the time but it is starting to happen more frequently. My SES light has been on for a while now but I finally got around to scanning for codes and it came up P0100 "Mass Air Flow (MAF) Circuit Malfunction".

I have a Cali Spec GTZ so it has 4 02 sensors, 2 Pre Cats and 1 main Cat which are all a pain in the ass.

My last full tune up was less than a year ago, all the usual stuff. Oil change, New Cap, Rotor, PCV Valve, Plug Wires, Air Filter and 6 New NGK Iridiums.

Recently my gas mileage is less than what it should be. I just took a 600 mile drive from North Carolina to New York and I'm only getting about 200 miles per tank.

Just last week I replaced the Distributor, Cap, Rotor, Air Filter, TPS, and IACV. All brand new from Advance Auto Parts. (No Junk Yard Parts) and still no difference. The P0100 was the only SES code so I replaced the MAFS today (also from Advance). I replaced the MAFS and cleared the SES code. It ran fine for about 2 hours and then the SES came back on and the problem came right back.


I'm not throwing anymore parts at the problem until I have a better idea WTF is going on.


Any suggestions are welcome.


PEACE...

[Galanttuner10]

check for vacuum leaks or any intake leaks after the mass airflow sensor such as throttle body gasket or intake manifold gaskets as its probably an unmetered air issue like i have going on with my car. let me ask you this, does the problem get better the more you drive it like after 20 minutes of driving it if idles better?

[GeeMode]

Actually, it doesn't make a difference if the car is warm or cold. But I think I see your angle...The metal to metal joints would expand and seal up any potential gasket leaks once the engine got up to normal operating temps.

Maybe I need to check for vacuum leaks anyway. A visual hose inspection is all I can do right now. I heard the "Carb Cleaner" method is a bit dangerous. And what about the propane method?

Maybe it could be the damn "new" MAFS is bad. It is a Cardone Reman. I seem to have bad luck with Reman Cardone shit. I have to wait until the Advance Auto in Yonkers gets more in. I just bought the last one.

[GeeMode]

Almost 100 views and no replies? Hard to believe I'm the only one that's had or seen this issue before...

[02redgalant]

On my 4g64 it was the MAF,same exact symptoms..mine wouldnt even let me WOT would rev max to like 2k and misfire or randomly stall..i'd swap the maf again to be safe and reset the computer ..it could also be the Throttle position sensor but you mentioned you've replaced it ...so to be sure did you properly wind it?not sure if the v6 is the same but on the 4cyl you actually wind the sensor on the throttle body sensor shaft(not sure if its the right term) instead just slapping it on the FSM actually tells you by how much visually .....

[GeeMode]

I'm concerned about the code being p0100 as opposed to a specific code involving the sensor itself since it as other components within it such as the IAT and baro pressure sensor which would give a more specific code. Like I said, I tried 3 different manufactured MAFS from Advance auto and the code still came back. As far as the TPS...I actually had to readjust it on the shaft after I installed it. I used my multimeter and back probed it to get the correct voltage at idle that's about it. The signal voltage now reads about .5 with the TB fully closed.

I'm ready to hit the dealer for an OEM MAF but they want about 500 bucks for one.