Ok I have an EP3 and it has about 160k on it. It was throwing code p420.I had a bad CAt so I bought a used OEM one. When I put the used cat on it threw p420 again so I reset the ecu again. It did this twice then finally went away. After about 20 miles of driving. I parked it and noticed the cel light flashes 5 times with key on engine off. When I looked it up it said it was probally a bad map sensor. Well I reset the ecu and then drive another 20 miles and the cel came back on. Well when I plug in my scanner to check the codes there are no codes present, just the 5 cel blinks with key on engine off. Does that mean I might have a bad pcm?

 

When was the last time you changed you plugs? I would run a couple tank fulls of super( for the the ethenhal) and may be run some V-Max fuel treatment through there.

 

Or some lucas oil feul system cleaner.

 

I like the z-max stuff, It really works.....

 

I think I'll try that next. I usually would start using a bottle of the Lucas every other oil change and it lasts for a 100 gallons of usage. Is the Z-Max available at autozone and places like that?

 

Yea, its like 20 bucks a bottle.....but it pretty much cleans off the backs of your valves in one tank full.....good stuff.

 

Nice, yeah I'll give it a try lol, where's the OP?

 

I got off the phone with the dealer today and they told me that the ecu is in learning mode. The ecu is learning map load and that if I take it on a couple hills and floor it for 2 seconds here and there that it will go away. Im posting this for others if they have this problem. Thanks though.

 

It just means that the ECU readiness monitors aren't set to "complete" yet. You have to put the car through a couple of drive cycles after you reset the ECU. Once the "not ready" monitors are all set to "complete," then it will stop.

 

You know how I can tell you're only 19?

 

Because my profile says so...

 

haha lol

 

What made you think it might be the MAP sensor?
Did it throw any other codes other than the p420?
When you last checked for codes with the scanner did you look at the freeze data?