[Murdered tundra]

A few years back my truck had a rough idle where it would just from 500 back up to 700 then back down without stalling had the throttle body blow up after trying to clean and regrease the fly by wire system. Ended up putting a used throttle body in problem persisted and ended up taking it to a mechanic who replaced the MAF with no improvement they said rough idle was normal. I moved north and have been dealing with a few days of negative temps here, after running the truck at 70 mph for an extended period of time when I stop at a light and idle drops my oil pressure gets extremely low my friend said it could be the IAC and we might be able to clean it but idk if I’m on the right track throttle body and MAF have been cleaned recently with no codes

 

[Murdered tundra]

It’s an 02 limited v8 with 270k miles trans replaced recently

 

[Murdered tundra]

I dont think the 4.7 uses an IAC. Check fuel pressure while running.

surging idle might be a vacuum leak. Any split ends on the vacuum lines?

I replaced all the lines a few years ago but may have failed with the cold I’ll have to look into the fuel pressure