[RCoulter]

Hello all. Recently I'd been noticing an almost rattling sound coming from under my hood. Took my car to Autozone and they said I had a P0402 code. So I bought a new EGR valve and replaced my old one. My car seemed to be running better than ever, that is until the it warmed up and I started hearing the same sound.

On my way to work this morning it never made any noise, but I'm assuming that's because it didn't have a chance to heat up. I'm very car ignorant and can use any help. Thank you in advance.

[flatratetec]

If I remember correctly P0402 indicates "excess EGR flow". This is most commonly caused by a faulty DPFE sensor. As for you noise... it's probably unrelated to the P0402 DTC.

[shinerstang]

+1. Rattling usually means a bad idler or tensioner pulley.