I had the same experience as the original poster. My aftermarket heater core purchased on ebay from FCP also burst and it matches those pics posted exactly, one huge crack along plastic. Happened after about 4 months. I didn't want the hassle trying to get it replaced(buy another new one, ship old ...

For the P0442, check the J Hose at the charcoal canister for cracks. Clean the hose and look real carefully. Here is a video on it.

When you replaced the coil packs, did you replace the plugs or take a look at them?

I bought from FCP on ebay, an aftermarket for 70 shipped. Fit and works fine, although doesn't seem to get as hot as old core, I think it has less/thinner fins or doesn't hold as much coolant. My old one may have been partially blocked too.

Here is a link to it. Came with the o-rings to. Its an ...

You need to find out where the leak is. While the car is cold, I'd inspect the coolant with a clean white paper towel to look for color, milkshake(coolant&oil mix) bits.

Then I'd turn on the car, let it sit running for 20 mins or longer and look for leaks with a flashlight, inspect all the hoses ...

Well, whats wrong with it? You can add a can of freon but if thats not your problem, that won't work.

I wouldn't drive it that far. The crack will only get worse. That radiator has given 11 years of service, just replace it. Mine went out at 138,000 miles too. If you've already been driving with it leaking, you've been driving on borrowed time. Rent or borrow somebody's car for the weekend.

I bought one from Switch Doctor on Ebay, lowest price I could find at the time.That was about 6 months ago and its working fine. The switch was made by Scan-Tech.

I had that same code P1171 on my 2000 GLT-SE also. I cleared the code, cleaned the MAF, and it was back within 2 weeks. Almost left me stranded if I didn't know you could unplug it, and limp home. Replacing the MAF fixed it. If its your daughters car away at school, I'd just replace it. I also put ...

I'd look and listen for an exhaust leak. I doubt its faulty 02 sensors if replaced with oem. See if the code returns. That said, if it is the original cat, its given 10yrs and 135k miles. Let us know how this turns out, as it seems to be a common problem recently. More people are posting p0422 code ...