[6ixer]

Recently my car had been making a rattle under the hood just after I. Tuned my car via the sctx3 flash tuner from AM. I was told by a fellow member of this site to go to the global spark and adjust it to -2 or -3 depending on how far AM may have advanced the timing the. So I set the global spark to -3 ran the car for about a month NO problems out of no were I here the pinging rattle. So I had to retune the global spark to -5 and then that appeared to stop the rattle.
This rattle has occured from under the hood both times.

I know its not the gas because sence th first rattle I've been using mobile gas and just to make sure it wasn't the octane I filled up on 91 and ran the 87 tune and then the 91 tune with the same global spark.
Returned it to 87 oct and retuned to -5 and its gone

Why all of a sudden was -3 not "good enough" and then its need a retune

Fuel filter is 5k old
Spark plugs are motorcraft and are used but all look brand new and no wear marks
Cleaned my k&n air filter (drop in cone filter)

The ping was identfied as by my father and auto zone guy as a valve rattle due to pre detonation and I told them that it was tuned by a hand held and they said many times they willadvance the timinga little for a better spark and hp so try retard the timing a little

What's the word??? Any advice what cause the rattle to come back or the timing to all of a sudden not be good enough??

[mcqueen]

i you can find 93, try filling up with that and see if the rattle goes away. if so, the timing is either still too advanced (unlikely) or the station you fill up with might have gotten some bad gas. also, fuel tends to be shittier in the winter so if you knock the timing down anither degree or two it might stop the rattle (then just advance it again in the spring).

[6ixer]

Yeah I understand but why would americanmuscle, well bama advance the timing that far vs stock timing and then not knock it back when I asked them I had to ask a fellow member about it and then he said try -2 oe -3 and I did (-3) and then it rattles again so I had to retard the global spark yet 2 more to -5....what would happen if I went to negative or if it was way to far advanced

[xtreme 2]

an NA can go to 18* of timing and still be fine. I doubt the spark advance is your issue, since that doesn't become a detonation factor until you are blown...

When did you last change your oil?

[6ixer]

last time i changed my oil was about 1.5k miles ago and i did it at 3k if not like 100 miles over but i run ford synthetic blend so 100 miles wouldnt hurt(i needed to get paided first lol)
and even sence then i got the tune 2 oil changes ago so about 6k miles ago theres was NOTHING and i mean nothing wrong with the car not even a faint rattle or anything like that under the hood and then i get the gears installed and all of sudden rattle