HELP!!!!!! 2002 Intrigue3.5L wont start

Okay I got rear ended at a stop light today no body damgage or nothing,(until) I drove 50 miles the engine light came on so I went to autozone and had it tested the code was p0420 (explainations) o2 sensors, faulty catalytic converter, engine misfire or running condition, large vacuum leak or engine oil leakage into exaughst-valve guide, seals or piston rings. eh no biggy my guess was it was probably how she hit me she busted a weld on my fairly (less than 4 mos old) new catalytic converter. Go to start my car and I get nothing no click no grind chuggin nothing accept all of the lights were still working. The engine light, the service engine soon light, and the brake light were all on the guage cluster. in the On position the brake light and the svs light came on after a few mins. No security light. I dont know what she knocked lose but I noticed my engine felt like it was running differently after she hit me but I thought I was over exagerating or something. Long story short my car is sitting in an autozone parking lot gathering snow with no other codes other than the p0420 code. I hear alot about the ignition issues with these cars but i'm not positive. I know some newer cars come with a kill switch in the rear that flips when in an accident that cuts out the gas and starter is it possable we have one?? Or a ground wire something. PLEASE HELP..

Also I forgot to mention that after the accident I now only have 2 settings on my climate control. high and highest. Dont know that this will be of any relevance.

Rhaigh08, The onlything that I can think of in the rear of the car that would cause drivability issues would be the emissions canister, which I believe is behind the passanger wheel well.

I've never worked on this system, but I believe there's some vacuum lines that run back to the canister. If you got hit hard enough there's chances that you cracked the canister and now your car's running with a vacuum leak.

These are just postulations. Did the rear bumper cover come off in this bump? Our 2000 Intrigue was hit at 40 mph in the rear end by a small honda that went under the bumper. This caused damage to the exhaust, but I believe the body shop left the cat converter on the car.

The heater control only having two positions is a blower motor resistor. I really think that's unrelated to the accident, but that's just my input.

There is no rear kill sensor in the Intrigue. Some Ford pickups have them, but I've never seen something like that in a GM product.

Good Luck.

Have you checked all ignition related fuses, especially those in the fuse box above the battery? The blower issue is interesting because a faulty blower resistor would result in only the highest setting working. I'm wondering if your battery is putting out enough juice? And have you checked the connections lately?

P0420 is almost always due to a faulty cat or 02 sensor. So, I think you're right about the cracked cat, she may have hit your tail pipe and put stress on it. But I guess that's the least of your problems right now...

BTW, the evap canister is actually located behind the drivers side rear wheel, but it's fairly well protected and I don't think the car would throw this specific code if it had a vacuum leak.

Sorry it took so long to reply to these. The car finally started and we took it to the shop. Once they plugged it into the scanner it had some codes. I guess the anti thefts were enabled and the guy at the shop says it locked out the starter and the fuel pump. Which was why we couldnt get it started. They just reset them and all codes have stayed off for 800 miles. So all is good now. No the bumper cover did not fall off it's just a bunch of scratches and dents. Which she is cooperating and is going to replace.