I've got a 1999 Accord 4cyl automatic, and I've had a CEL for an EGR valve fault for a few months now. I had the EGR valve replaced at a dealership about 5 months ago and the CEL has shown ever since then, though I haven't had a chance to go back and see why I'd be showing a fault for something they should have repaired. I'm wondering if it's possible that the sensor is just screwed up, or in the case that the EGR valve is still faulty, what's the worst that could happen to my car by driving it in such a state for several months? It seems to run normally, although I've noticed some hesitation and jerkiness in the engine under certain conditions.

On an unrelated note, I pulled the underbody plastic covering near the front of the car off on a parking curb recently, and I'm curious if there is any functional purpose to that cover other than keeping road grit out of the engine bay, and if it's worth replacing it?

 

For best responses, post the DTC (Pnnnn) associated with your fault. There are several EGR DTC's and they point to different possible faults.

Undercover stablizes the bumper, but is probablly not essential. A lot more dust/debris will be pushed up to the top of the engine.

good luck

 

Hey Dan,
I have the same car and the EGR code ( P0401) usually wont go away by buying a new EGR. You are going to have to remove the upper intake plenum and clean the the port holes. They are probably clogged.
You should buy a new gasket just in case. Good luck.