Engine rough idle - EGR code and EVAP failure

[Faizul Hasan]

Experts here,

Looking for expert advice regarding rough idle and EGR, EVAP failures on my car Audi A4 B6 2004 1.6 engine. I have sporadic rough idle. When I scan, I found two issues. 

1. EGR System
   1. Regulation Divergence : P1403 - sporadic 008-Implausible pulse
   2. Potentiometer for EGR (G212): Signal too Low : P1443 - sporadic 007-Short to ground
2. EVAP - failed

When I talk with my service provider (not the Audi agent), they didn't worry about EGR issue and told it is exhaust gas related so to ignore it. They didn't say anything about EVAP (I also forgot to ask it later ). When I study about EGR and EVAP, I found that these two can contribute to rough idle too. I have sporadic rough idle and I have sporadic failures (both I don't like at all). So I feel these two could contribute to the sporadic rough idle my car faces. Interesting thing is that so far I didn't feel this rough idle when the A/C is ON. But my service provider seems they are not interested in fixing these two.

My question is, do I need to worry about these issues and pressure them to fix? Because I feel the sporadic rough idle would be fixed by fixing these two?

 

Thanks in advanced.

 

Edited June 16, 2019 by Faizul Hasan

[Twin Turbo]

Hi and welcome to Al,.

Change the sparks.

Just take your car for a week end outing on a highway of your choice.

 

 

[Faizul Hasan]

@Twin Turbo thank you very much.

I already changed the spark plugs (~10k drove after changing). I wonder if I have to replace ignition coil or distributor cap.

6 hours ago, Twin Turbo said:

Just take your car for a week end outing on a highway of your choice

Do you suspect there can be some carbon deposits which need to be kicked out?

[Rumesh88]

Get the EGR cleaned first.