Check engine light flashing, car runs bad, no codes?

[zx150]

My GF has an '02 Focus with 160k miles, auto trans and it started running poorly today on a steep grade. The check engine light started flashing, the engine started to run poorly and there was an overwhelming smell of burning eggs and sulfur. Pulled to the side of the road and the car was coughing like it was about to die. It kept acting up in the same manner on the next few hills.

We did about 150 HWY miles afterwards and the car ran great the further we went. After the trip I tried to run the codes and the computer wasn't throwing any?

It's never acted up like this before. Cat converter? Definitely felt like the engine had a miss and the performance was cut way back.

[elsolo]

-rotten egg smell
-runs like crap
-no codes stored


plugged up cat converter would cover all those symptoms

[zx150]

Originally Posted by elsolo

-rotten egg smell
-runs like crap
-no codes stored


plugged up cat converter would cover all those symptoms

That's what I was thinking.

How much does a stock replacement cost?

[anarchy0392]

A flashing CEL means sever misfire. So ^^cat, plugs, wires, or coil pack.

[elsolo]

Originally Posted by zx150

That's what I was thinking.

How much does a stock replacement cost?

look on rockauto.com

[amc49]

When was the last time a cat went bad instantly and then fixed itself afterward??? He clearly says it 'ran great the further we went'.

The smell shows converter at least WAS working, maybe not so much now, but something else happened there to do it. Something to run the engine super rich, or ignition failure to throw lots of unburned fuel in exhaust. Change cat and that is not going away. Plugged up converters don't run better later, the damage does not repair itself.

I wouldn't waste a cent on a new cat until I found out what did that.

No one has struck the underside of car at any time in there have they? Hit cat just right and it can shatter like pottery inside if the matrix is a ceramic one. BTDT, thank you A&B Muffler Shop.

OP should have the after cat O2 output looked at by someone who can read realtime data. That'll show condition of cat.