Twisted

My car still pings under hard throttle sometimes. I'm running 12* of timing--down from 14*, and I'm running 91 octane. I haven't been able to find any vacuum leaks, and I've re-torqued my intake manifold bolts. I've also run a Techron treatment, which seems to have helped, but not solved the problem. I get no codes except for one regarding my neutral safety switch. Has anyone solved a problem like this before?

stocksuspension

ur having a mechanical knock! its caused by deposits on ur valves... u need to vaccu flush the motor and drop down ur timing

Twisted

Thanks for the reply, Stock. Yeah, I was thinking I needed another decarb treatment. I wonder if Seafoam will do the trick.

stocksuspension

i use vaccu flush.. ford uses that for its treatments, u want about a bubble a second.

91stang

is 91 the highest you can get? here i can get 93 at every station pretty much

AdderMk2

you still shouldnt have a pinging problem with 91 octane on 12° timing... Im running 12° now and I use 89

The deposits does infact sound like the most probable issue. a good deep cleansing with a carbon remover should help alot

Twisted

Thanks, fellas. I guess I'll find a good cleaner and try that.

HACKGT350

yes get the seafoam that stuff worked great and its really fun to watch too

91stang

i've heard both good and bad things about seafoam... like one of my friends used it on an engine that ran fine but did it to clean it out and then a week laster his car stopped working. this could be other causes but idk

HACKGT350

that sounds like other causes too me