Engine has quit
 

A few days ago I was driving along and I felt a hiccup in the motor. Within another 3 miles it got worse until the car just died. I had it towed home and now it will start and run (poorly) for a few seconds and then sputter out. I used my reader and the codes are as follows:

P0300 Misfire Dmg to Cat
P0301 Misfire Cyl 1 - Cat Damage
P0304 Misfire Cyl 4 - Cat Damage
P1313 Misfire Cyl 1 - Emissions Related
P1316 Misfire Cyl 4 - Emissions Related
P1319 Misfire - Emissions Related

Here's what I am thinking about doing....Any other thoughts before I start ordering parts???

New MAF
Coil Packs
Plugs, Plug Seals and Connectors (I was planning on doing this w/my next
maintenance anyways)
O2 Sensors (all 4)
Fuel Filter (another maintenance planned item)

I was wondering if there is a preventative need to do the AOS as well.

Thoughts?

Thats what our cars do on the Vipers when the cats go bad.... Over on the VCA sites the discussions are that this can happen after an over-rev. Not sure why but thats what happens with them.

Dig deeper. You still need to find out Why the misfire on cyl 1 & 4. Changing sensors may solve nothing except wallet weight reduction.

Any other codes?
Year, model, mileage?
Recent mods or repairs?
Any other symptoms?

Thanks for the replies
 

It is a 1997 Boxster with 52k miles. It is bone stock except for the GAHH top, desnorkled intake and Pedro motor mount. It has been running great with no issues and I was just driving along at 50 mph when it started hiccuping. I did clean the MAF last year as the check-engine light came on. That was about 6k miles ago.

I have driven it a little more aggressive on a few drives with the local Porsche club, but not hard. I don't believe it's been exposed to any over-revving type conditions.

I would pull the oil sump plate to check for metal etc. in case your IMS bearing is dying & cut open your oil filter too. If everything looks good then I would buy a new set of good sparkplugs & install them while carefully inspecting the old plugs especially cyl. #1 & 4. Swap coils with connecters from #1 & 4 to a different position to see if they are faulty. Then start car & see if it needs anything else. Your AOS will tell you when you need to change it until then don't touch it. A new AOS may be worse than the one you have.

Why would that be? Just curious...

My original AOS lasted 85K miles the last 2 new AOS I bought lasted 200 miles. If it works it works, if it doesn't work it smokes.