I need some advice. 4 weeks ago, I got water in my 2000 3/4 ton 6.5 .It got by a 3 day old filter and destroyed my IP. I had my pump rebuilt to spec,the GM mechanic put it back in,after flushing the system,here's my problem. The truck has a very rough idle. Starts good, but I took it out around the lot,it feels like it's missing or out of time.I need help. What can I suggest to my mechanic to help resolve this?Also, no codes. Thank you in advance,I need my truck back.