My car pings with mid-grade in it. It only seems to like premium. I've checked the timing and it's at factory specs, what else can I check and mess with to try and get it running with at least mid-grade again?
Go to a shop that has the fuel and engine cleaning system that pulgs into your fuel rails. It'll get a good amount of carbon buildup out. Check your fuel pressure at WOT. Your pump may be on it's last leg and leaning out towards the top. Your initial fuel pressure may be low as well. Also check your timing. You may be too far advanced.
there's lots of stuff that can cause what you're talking about. These are just 'some'.
Would a fuel pressure gauge that threads into the fuel rail work well? The kind that you thread onto that relief nozzle or whatever it is? I guess I could trun some of that seafoam or whatever through it too huh?
CManT1914 said:
I've checked the timing and it's at factory specs...
im with Daggar. i would think about carbon build up in the chambers which artificially raises the compression ratio. also make sure the balancer did not slip.
have you pulled codes? a malfunctioning EGR can cause detonation (if the EGR is not opening when it should, the less volatile higher octane could be helping to ward off detonation).
good luck.