Coming home last night (temp in the high 60s), I started getting the "clank" noise that the grid heater relays make, and the alt gauge was dropping and raising. I thought this was strange since the truck was totally warm, and the only difference I noticed was that at light throttle the motor would be a little rough with a "rump, rump, rump" kind of sound. I got home and parked it. As I gathered my things to go in, the truck kept clanking, even though the truck was off. I raised the hood and couldn't distingush were it was coming from, except MAYBE the relay mounted to the drivers fender near the firewall that isn't a grid heater relay. Didn't have time to mess with it, so I left it. Came out this morning and it lit right off, and didn't do it again
Have you guys seem anything like this, and do you know what I should do or what to check?
Thanks,
Jim

Thanks,
Jim