What amount of pinging is considered normal in these trucks? No Ping, very slight ping at the beginning of throttle pickup (like when you are riding along at 50mph and push the throttle slightly to accelerate), or ping throughout the range?

The reason I ask is I have a 99 F150 5.4 with 123k miles. It has always had a very slight ping at throttle pickup while traveling at speeds of around 35 to 60mph. I mean you can hear it ping 1 to 5 or so times which occupies all of a fraction of a second and then it is gone. It does not do it from a dead stop or when accelerating hard or uphill. It does not do it when it is cold either. The outside air temp seems to have no effect. I also have a predator for it. It did it with the stock program. It doesn't do it at all with the diablo tune program until after the program has been in there for a week or so. I drive about 500 miles a week. It seems like it "learns" to do it.

So, what is normal?

I have cleaned the MAF and throttle body. It is starting to get a little hitch in the idle and predator will often show a misfire at idle if I record a real time data log. It does not throw any codes for misfire and it only shows an occasional misfire and only at idle. I imagine it's almost time for an IAC valve.

Also for anyone who may be in the know....what values should I be seeing on the predator for knock sensor, timing, fuel trim, and O2 sensor readings at say...idle (16% engine load, 600 rpm) and 72mph (49% load and 2000 rpm)???

 

anyone have a comment?

 

Apparently not
lol


A little bit of a ping is ok. That means that your timing is as far advanced as it can be which should help power and mileage.
Too much pinging isn't good though. It sounds like your's is probably ok.
How old are your spark plugs? Have you checked for vacuum leaks?
I would fix the miss before I did anything else.

Your knock sensor should read around .1V until it starts pinging then it will go up.
Spark Advance should show about 12-17 @ idle, 32-40 @ 30 mph and a bit less than that @ hwy speed. With the Predator it may be a bit higher than those.
Your Short Term Fuel Trim should fluctuate above and below 0 consistantly. No more than about -10 - +10.
Your Long Term Fuel Trim should be in the roughly the same range but should be quite steady.
Your O2s should fluctuate between around .2 - .8V. When you accelerate they will go rich, up to about .8 or so and stay there until you're back at cruise. When you decelerate they should go lean for a bit until you're at idle or cruise again.
Your MAF should read between .7 and .9V @ idle, 1-1.5@30 mph, 1.5- maybe 3V at hwy speed. If your MAF readings are way out it can cause a rough idle and ping.

 

I took the IAC out and cleaned it. The misfire appears to be gone and it does idle a bit smoother. It never tripped a code for it, the misfire only showed on the predator along with the bit of roughness at idle. I think it's running just fine now.

However, I'm an A type personality....

I do still have some questions about the predator though and this may be the wrong forum for it, but the data I get when I run live data is pretty close to what you say it should be. I am not sure what the knock sensor reading is relative to, but it reads 1023V before I start the engine and stabilizes at 17V.
At highway speed (72mph and 2000rpm) its usually 55ish. Highest I've seen it was during hard acceleration and it was 72V. It didn't sound like it was pinging.

The spark advance is also like you say except at highway speeds it's still 32-40, usually 34-36. It drops to 15-17 during hard acceleration at same speed.

Long term fuel trims are usually 0 +/- 2 and short tems are 0 +/- 5.

I don't recall the MAF at the moment, but WHen I have looked at it, it seemed very responsive.

Like I said, I think all is good. I just am unsure of what some of the things I see really mean.

 

I'm not sure either about your knock sensor readings. Anyone else have any ideas?
I'd say your spark advance is probably ok. The Predator changes it from what Ford originally intended.

 

I stand corrected on the spark advance at highway speed (72 @ 200rpm). It stays around 28. I think maybe the knock sensor value is in millivolts which would correspond what I see now to what you say about ping occuring around 0.1v (100 millivolts).
There are several other values given in various places in the Predators diagnostics where the unit of measurement is Metric but the value returned is actually SAE and vice versa. It's a wonderful tool, but it could use a little spit and polish here and there and it definitely could use better documentation for the diagnostics.

Thanks for your answers, I appreciate it alot!

 

i have to throw in my .02. i've seen many complaints on this forum about this pinging, seems somewhat common on 4.6/5.4. i can't comment on the chips, but i did see a post some time ago about water circulation in certain areas of the cyl heads , it gets slowed down over the yrs due to crud build up and causes some cyl's to run hotter. this is prob. what has happened to my wives '97 g. marquis, it pings like crazy, 91k, 4.6, been doing this for prob. 3 yrs or so. i thought it might be the cats starting to get plugged, causing a bit higher cyl. temps, or carbon build up over the yrs in the heads. i have also heard that the pcm can be flashed only if there is an "upgrade" available. but this wouldn't help if your running a chip. maybe this is .04 worth? good luck.