I had a tune by a reputable guy. What causes this(plugs,octane,Air-Fuel mix)?? Is it harmful or dangerous?
Pinging
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
But I have to first ask two questions:
1) How do you know its pinging? I mean, the factory PCM sensitivity settings on the knock sensors will pull out timing really quick so you should not hear it.
2) Has your car been modded and does it have new new tune? Because if it does, there are a number of setting that could have been changed...including reducing or completely turning off the knock sensors.
Last edited by Mez; Nov 2, 2009 at 08:19 PM.
Safety Car
Joined: Oct 2003
Posts: 3,644
Likes: 13
From: South of Boston MA
My '01 had a minor issue with pinging under WOT. A friend with a '97 had a similar problem. I had my car checked at a GM dealer who found nothing out of spec. Fuel injector cleaner didn't help nor did octane booster. I lived with it. No pinging at all with my '08. 
Instructor
Joined: May 2007
Posts: 234
Likes: 3
From: Wexford, PA
You need to scan the car to see if you are getting any KR. This will confirm what you are hearing. Do you feel an loss of power...if the knock is bad enough you are hearing it, your car will be pulling alot of timing.
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Drifting
Joined: Apr 2006
Posts: 1,276
Likes: 5
From: Ambler Pa.
I have had a similar experience. Tuning can totally eliminate it. Also it is beneficial to run a 160* thermostat and 1 heat range colder on your spark plugs. Cold air induction is also very helpful in mitigating this condition. As you reduce heat , you reduce the amount of timing you have to retard to reduce the pinging . The more timing you can keep, the more power and throttle response you will have. Another alternative is to kill it with octane, but that is expensive, the 2 points you referenced is actually .2 octane units , you would have to use 5 bottles each tank to raise 91 octane to 92 octane. And 92 still isn't enough, 94+ seems to be the magic number at sea level.
Thread Starter
5th Gear
Joined: Aug 2009
Posts: 5
Likes: 0
I have had a similar experience. Tuning can totally eliminate it. Also it is beneficial to run a 160* thermostat and 1 heat range colder on your spark plugs. Cold air induction is also very helpful in mitigating this condition. As you reduce heat , you reduce the amount of timing you have to retard to reduce the pinging . The more timing you can keep, the more power and throttle response you will have. Another alternative is to kill it with octane, but that is expensive, the 2 points you referenced is actually .2 octane units , you would have to use 5 bottles each tank to raise 91 octane to 92 octane. And 92 still isn't enough, 94+ seems to be the magic number at sea level.
