viza

The manual says to use 87 octane gas. Once my engine was broken in and I started pushing it, I noticed valve noise at about 2800-3000 rpm when the engine was under load. I talked to the dealer and he said to try Shell, Sunoco or Texaco gas. I tried all of them and it didn't go away. I think the timing curve is wrong for those RPMs, at least on my chip.

It's not too bad but I can hear the valves at those RPM's with 87 octane gas, and that's never good. Recently at my last fillup I ran the tank down to 10 miles left, and switched to 89 octane and the problem went away. This is the first time I've used anything but what the manual recommended.

Anyone else get this kind of predetonation at those RPMs? My engine sounds a hell of a lot smoother at all RPMs now... Should I go get a better tune done or something?

-Viz

grampa_stang

Always run the best grade possible. Forget 87, forget saving $2.00 a tank. 91/93
whatever is available...better performance, better mileage. Your car will thank you.

viza

It's not about the money, I was trying to follow the manual so if something goes wrong, they can't say "Well the manual says use 87 and you used 89, bye bye warranty, bend over". I think the price difference adds up to about $1.50 a tank ROFL. New cars and warranties make me nervous about deviating from the manual LAWL.

At the same time, manuals aren't perfect (neither are factory tunes)...

-viz

marcuskeeler

I'd nudge up to 89 or 91 if you need to, warranty issues won't arise from that. If you continue to get pinging I'd drop into the stealership and get one of the techs to test drive it with you to get it on paper. That way, even if they don't do anything, you'll have some kind of paper trail signifying you attempted to get them to address the problem.

howarmat

get some good gas, shell or BP and higher octane....if you still have problems with pinging (expecially since 3000 isnt really under any load) you have more problems.

Derf00

Without a tune it will do nothing for your in either of those respects.

The pinging that is being heard is probably because the timing is wrong at those RPM's (too advanced), the fuel is bad, or he has carbon build-up (not likely on such a new car). Higher octane on a new caris only a band-aid fix for a bad tune or some other problem.

By using your logic you are throwing money away. No if-ands-or-buts about it.

Derf00

Your initial idea of going to the dealer and having them redo the tune is probably the best. You could also have them do a diagnostic on it and since it's under warranty, it shouldn't cost you a dime. Just time.

Dex

i bet its the rattle on the clutch plate

grampa_stang

I give....I'm running 91 and always will. MaybeI won't get better mileage,
butI can tell you this...my car has never pinged. I also choose not to put
Kmart blue light special oil inmy car..sure it'll work...but don't we want the
best for our stangs. I'm using Mobile 1 full synthetic and I'm probably wasting
$$$.