#1
ThomasB81677 , 12-09-2019 11:32 PM

I am posting some of what I posted earlier here along with an update. I really need help with finding out what has happened to my car.

Ihave a 2005 Monte Carlo Tony Stewart with a supercharger. It’s a V6 3.8 engine with 247,000 miles. I noticed about 3 months ago it started stalling at low speeds basically 10 mph, in parking lots, when I would take my foot off the brake. The RPM’s would revv up and down at stop lights and I kept getting horrible gas mileage. Literally 50-70 miles less per tank.



I replaced The MAF, Air Control Valve, Throttle sensor and it did the same thing. About a week and a half ago one night it got to where I couldn’t go past 40, barely made it home. Drove around the block and wouldn’t go past 10 mph. It just wouldn’t let me go any faster. Then it was 5, then it just wouldn’t go, but would still start. Now It cranks, and acts like it wants to start but doesn’t and the battery is draining. I think it went into failsafe mode to be honest. We got the code P0112 today, which has to do with the IAT censor and The PCM.

I just have a few questions I hope someone can answer. Would a bad IAT censor cause all of that? Would a bad air filter cause all of that? The filter hasn’t been replaced in forever. Would an alternator cause all of that? I don’t think the alternator has ever been replaced. I am completely lost at this point and don’t want to blow any more money on wasted parts. Anyone else deal with this code before?

 

Just throwing a guess out there . Kinda hard to check now that it's not running but did you consider the catalyst converter might be plugged ? With it constantly loosening speed did you notice the exhaust sound change or pick up a whistle ? When running you can put your hand over the tailpipe and check restriction. If you have time pull one of the O2 sensors and see if it starts and perhaps run better. Like I said it's only a guess. Testing if free so it's not like you're blowing parts at the car . Good luck