I have a '06 Hyundai Matrix 1.5 Crdi. It was unfortunately subjected to the wrath of "Ondoy" last Sept.(underwater for 2 days) I was able to get it running from November till the beginning of April , after several (non-casa) repairs. Now the problem is if i go at around 34-38kph or push a bit heavily on the accelarator the engine cuts out. I can start it up again but it will always shut down with the same circumstances. Is this an EGR valve problem? Hope you guys can help.

Thanks