No Power but with blinking SES

[ColoBonne]

For a couple of weeks, car has had almost no power.
If I'm light on the gas, will accelerate normally.
If I drive normally, right at 2300rpm the engine feels like it's cutting out/missing and the SES light comes on blinking.
When I let off, after a few seconds to a minute the SES light goes out, and will cruise normally.
The code is P0401, EGR flow is insufficient. I've put in a replacement EGR valve from a junk yard (don't want to spent $120+ for a new one right now) no change. I've checked all the EGR piping, no clogs.
In park or neutral, it will rev up normally.
What could be the problem?

[harofreak00]

Blinking SES light means you have a misfire. When is the last time you changed the plugs and wires?

[ColoBonne]

Just put in new NGK TR-55's about a month ago. But didn't do the wires.

[harofreak00]

Chances are that when you removed the wires, you damaged them and now that is causing your misfire. I'd replace the wires.

[wjcollier07]

I agree with Andrew. Good chance it has something to do with the spark wires integrity.

I once had this problem with an '88 Mustang..and because it was only the 2.3L 4 cylinder, the two wires that were damaged wouldn't really let it run.

Consider getting Napa Belden or Autolite Pro wires.

[Archon]

A lot of what you are describing could also be caused by a plugged cat.

[ColoBonne]

If it's the wires, why would it be throwing a code for the EGR flow?
If it's possibly a plugged cat, would it still be able to rev up normally in neutral (4000 rpm) with no stumble or miss?

[BillBoost37]

Blinking SES light means you have a misfire. When is the last time you changed the plugs and wires?

Technically speaking that is not fully correct. The FSM states a blinking check engine light is the pcm's way of communicating a "possible catalyst damaging condition".

While many of us see this when misfires occur, it could be caused by other items as well.

[Archon]

Yes, with a partially plugged cat, the engine can free-rev properly, and run normally with light acceleration. It's at higher loads and engine speeds that the problem often shows up.