Ok, so I've tried both 5 Star and VMP to tune my 2010 5.4 via a SCT.

Problem is, even after multiple revisions by both companies, I still hear pinging under acceleration. This typically happens under light throttle changes.

Both Mike and Justin have been great to work with but I'm not sure what to do next. They are both 87 Performance tunes.

Is it possible that I'm hearing something other than engine ping? Could it be something in the transmission?

Advise?

Thanks - Jeff

 

Try a different brand of gas?
Try 89 Octane?

 

Sounds like you have "light" pinging? Can you retard the timing with your SCT device? I think you can. If so try retarding it the minimum amount and see if that helps. If the pinging still occurs, try retarding it more - it should eventually stop.

- Jack

 

I would try better gas then 87. Try 89 and 91 and see if it goes away. If you keep taking timing out of it you will be taking power away from the motor.

 

That's correct, which is why I suggested retarding the timing by the smallest amount and working from there. These engines are designed to run on 87 octane gas, they should not need a higher octane mix unless the timing has been advanced too much, which may be the case in his tunes. Different engines have different characteristics, and, due to production tolerances, his engine may not be able to run properly on the timing that was set in his tunes.

Using a higher octane gas than the engine is designed/tuned for is like throwing money away, and may result in less power too if the timing is not advanced properly to compensate.

- Jack

 

^^ Good points.
But, since the OP said he has had "multiple revisions with both companies", I would imaging timing issues would have been already addressed by the pros.
My thought was that the prob might be caused by something else out of the control of the tuners. That's why I suggested to try octane and a different brand of gas.
But you have a good thought.
If it was me, I'd ask the tuners if timing changes had been tried in their tunes before I took a couople of shots in the dark.
But then, that's just me.

 

Timing advance has been reduced to basically nothing in the latest tune. I've tried 10 different brands of fuel and higher octanes. I was told by someone that sometimes the transmission can make a similiar noise but I can't confirm.

 

I would suggest getting a ScanGauge or something equivalent that you can monitor your knock sensor voltage with. If your engine is pinging the knock sensor will pick it up and reflect it on the Scan Gauge. You could be hearing a number of things, only way to find out is to actually wee what the engines is doing.

 

Hey OP, check out your PM's

 

Just for the sake of adding something, I'll add that if your tunes are written a bit too lean, that MIGHT cause pinging too.

I've never heard a transmission noise that sounds like detonation. Detonation or pinging sounds like "marbles in a can". It is a VERY distinctive sound. On older vehicles, a slight ping under load at times was not considered harmful. I cannot speak to this issue on newer vehicles. My understanding is, the engine should not "ping".

And, the knock detector in the engine will tell the PCM to pull timing if it detects ping, so you really should not hear it except only briefly. If you are getting more than that, and if it is "ping", then it's possible your tuner has turned the knock detection off in your tune - which is a dangerous thing to do (in my opinion). I would NOT run a tune that had knock detection turned off.

- Jack

 

We always considered it harmful on the older engines. The pinging is a result of the cylinder firing too soon which causes the piston to vibrate or hit the sides of the cylinder. This can cause damage to the rings as well as to the walls and the piston. Severe cases have broken rings. The optimum from a performance stand point was to advance the timing until it started a slight ping, then back off slightly.

 

Interesting, Jim. I certainly know what damage pinging does and why it occurs. But, I distinctly remember reading in automotive articles that a SLIGHT ping now and then UNDER LOAD (notice all the emphasis here) was not particularly harmful.

I had a Toyota pickup (don't throw stones) that did that from the day I bought it new. I tried retarding the timing the least little bit which absolutely killed the power. I finally set it back to spec and lived with it till I sold it at 110,000 miles. No damage that I could detect.

- Jack

 

When I hear pinging, I picture a piston trying to go sideways instead of up and I cringe. I guess if it is slight, there may be no noticable damage, but I would not be able to listen to it and live with it.

 

Sorry for the length oif this...
A while back, I had experienced some "light" pinging using my SCT but a revised performance tune took care of it.
Then, after several tanks of Shell and an oil change, my engine started to run what can best be described as more effeciently (less throttle needed at take off, just felt stronger).
So I decided to give the original performance tune that had pinged before another try.
After I put it in, it started to ping again intermittently but I felt more power and so I got in touch with the tuner to see if anything else could be tried.
While we were emailing back and forth, I told him that I had read the above quote. Because I never did that before and was hesitant, I asked if he thought it would be OK to try it,
He said yes but to go slowly in the RPM ranges where I noticed the prob.
So I retarded the spark -2 in the range from 0-2000 and -1 in 2000-4000 and left the higher alone. (Those being the lowest settings).
RESULT=NO MORE PINGING with the original more powerful tune.
So, thanks to JackandJanet for helping me to work it out and to the OP for the original post. And to Mike at 5 Star for the patience.
Hope this helps

 

You could datalog with those programmers and see what the knock sensors are picking up. That will confirm if it's detonation or not. You might also check for codes to make sure you don't have a bad knock sensor.