Help: CEL P0401 EGR Flow Insufficient

[happy_aggies]

I was cruising at 40 mph and suddenly CEL goes off.

I read it w/ OBD II and it says:
P0401 EGR Flow Insiffucient.

Anyone can help?

Thanks!

[Yanks0114]

have you altered your emissions equipment?

Do you just have a catback exhaust or do you have headers?

[happy_aggies]

I have K&N drop in that I used for couple months, Cat-back almost a year.
No headers yet. only SC w/ 6psi that also has been running fine for a year.

I did purchase an aftermarket fuel cap though (couple weeks ago) since it fails to vapor test (something like that)

[DavPak]

you might need a new EGR valve, or Vaccuum Switching Valve (VSV) for the EGR.
tough to say without having a scantool. using the correct scantool, you can control the EGR valve and find out exactly what the problem is, in this case at least.

good luck!

[happy_aggies]

Thanks DavPak!

I'll be out of town until Dec 1. I'll keep y'all updated after then.