Stupid Question Maybe... But there is something wrong with my brain

could be a timing issue - when was it last set? or maybe even as simple as your octane... if your running 87 your more prone to detonation. just my .02

Hey bud - good luck with the scan tomorrow.

Is it possible that after 4K RPM you cant hear the pinging because of the loud exhaust, motor, etc? As i get older, I have a harder time hearing stuff like that.

Have you been driving the car lately or is it 'here and there'? We (in the SW) have been so hot for so long, I dont think it is a new 'heat' related problem (that would have popped up a month - two months ago).

The easy thing to do is just back the timing down a couple and see how it does.

Good luck with the scan and car. Take care!

Camman said:

I believe I set the timing about 2 months ago. But I will definetally check it tomorrow. I guess it is very possible that I dont hear it above 4000 rpm. Ill check the timing, maybe it is too far advanced.

I am and have been running 87 octane for the last couple years. I dont see it suddenly becoming a problem. Of course I could be mistaken

Also, w/out egr function I would ping as well right? IIRC the inert gas serves both as a nox deturent and a 'cooling' agent as well? Timing it is for the time being. Thanks alot for the help and kind words!

Click to expand...

I also run 87 in the fox (similar temps for us - we have kissed 110* a couple times this year) with no issues. I run 10* but have been at 14* before during the summer on 87 octane.

You are right about the EGR. If one has physically removed the EGR, but not let the puter know about it (turned off the EGR function in the puter), you are right-on, that can lead to part throttle detonation (FWIW, EGR does not function at WOT). Obviously an EGR malfunction can also so this (valve stuck closed, position-sensor out of calibration, etc).

During EGR situations, the puter trims back the injector pulsewidth and dials in a lot of timing (as you said, the inert gasses reduce the volatility of the charge and cool the chambers). It seems to be hit or miss though on whether one will see the detonation with no EGR and no tune.

I like the timing idea. you could have even gotten a bad tank of gas. it happens. when you reset timing a few weeks ago, did you notice timing being a bit off from the previous setting (as if it had moved)? A slipped outter balancer ring can allow one to be advancing timing a bunch w/o realizing it.

I know you know all this bud - I am just thinking aloud with ya. Good luck with the automotive and physiological diagnostics.

wow, you got away with a lot of timing.

And you are doing better than I normally do, and I dont have an excuse.

Take care.

Cool you guys are getting away with running 87 octane, but I recorded a 4 mpg increase when running 93 over that 87. Sure you may have tried it already, but if not give it a shot for one tank. Mine would only ping at 80 mph in 4th at WOT, and I dont do that often. The mpg convinced me that is what it requires. My Dad has a 93 T-bird that only runs on 93, otherwise it pings alot. Good luck with your head dude.