Knocking (pinging) under acceleration
Thread Starter
Racer
Joined: Nov 2004
Posts: 494
Likes: 0
From: Charlotte NC
Knocking (pinging) under acceleration
Car is a 2001 with Blackwing intake and Corsa Pace car exhaust. Was dyno tuned in 2004. For the last few months the car now pings under acceleration (still using same 93 octane fuel). I replaced spark plugs and wires to no avail. No check engine light.
Any ideas of what might be wrong?
Any ideas of what might be wrong?
Advanced
Joined: Sep 2007
Posts: 93
Likes: 0
well only when im driving about 45 and i accelerate... not gunning it just accelerate about half way i hear i hear a rattling coming from the engine... that the only time i hear that sound. Only mods i have done on teh car are the hypertech chip ( i put the thermostat at 180) and a intake... any ideas?
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Thread Starter
Racer
Joined: Nov 2004
Posts: 494
Likes: 0
From: Charlotte NC
My tune was done over 3 years ago and never had any problems until about 3 months ago. I have not tried to put the stock tune back in it but I have no way to reload the stock tune. The place that did my tune went out of business. I would at least want to be able to backup the tune before I put it back to stock since I paid $500 for it.
Any chance the knock sensors are going bad?
Any chance the knock sensors are going bad?
Burning Brakes
Joined: Mar 2006
Posts: 750
Likes: 82
From: Bedford IN
I here ya on the tune! The other guy has the hyperchip tuner that is why I mentioned it. I am not sure if the knock sensors can make noise like that. Someone else is going to have to chime in on that.
Also is it different at different RPM, gear, speed?
Also is it different at different RPM, gear, speed?
Thread Starter
Racer
Joined: Nov 2004
Posts: 494
Likes: 0
From: Charlotte NC
Mine is not consistent with RPM, gear or speed. It typically does it when its under load around mid RPM range but sometimes its close to redline as well.
Thread Starter
Racer
Joined: Nov 2004
Posts: 494
Likes: 0
From: Charlotte NC
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
There is a new software update for the PCM from the dealers that is supposed to help this issue. I haven't gotten it put in for mine quite yet as they quoted me a high price to do it where as it should only take a few minutes or an hour labor charge.
Le Mans Master
Joined: Dec 2006
Posts: 7,251
Likes: 16
From: Phoenix Arizona
buy 93 octane fill tank half way then add one quart of torco then fill it up the rest of the way. drive it easy for 10-15 miles. make sue engine is nice and warm ( oil temp minimum 180 )and gas is mixed up
then run it hard and see if it pings.if it does not ping the gas is bad
G/L
i get this a lot around here...octane is not always what they say it is
and it changes week to week at the same stations! 
Thread Starter
Racer
Joined: Nov 2004
Posts: 494
Likes: 0
From: Charlotte NC
Add Torco what? Fuel?
They have 100 octane fuel at the gas pump here. Would it make more sense to try that instead?
Sam
They have 100 octane fuel at the gas pump here. Would it make more sense to try that instead?
Sam
he would lose his tune. your gas station may have changed their wholesaler or just are getting crappy gas now. try this only cost you twenty bucks
buy 93 octane fill tank half way then add one quart of torco then fill it up the rest of the way. drive it easy for 10-15 miles. make sue engine is nice and warm ( oil temp minimum 180 )and gas is mixed up then run it hard and see if it pings.
if it does not ping the gas is bad
G/L
i get this a lot around here...octane is not always what they say it is and it changes week to week at the same stations!
buy 93 octane fill tank half way then add one quart of torco then fill it up the rest of the way. drive it easy for 10-15 miles. make sue engine is nice and warm ( oil temp minimum 180 )and gas is mixed up
then run it hard and see if it pings.if it does not ping the gas is bad
G/L
i get this a lot around here...octane is not always what they say it is
and it changes week to week at the same stations! 
Racer
Joined: Sep 2006
Posts: 280
Likes: 0
If it makes you feel any better, I get some occasional pinging under part load as you describe - I get the best results with Hess 93 octane.
Other than that car runs great, plugs look fine, not using oil.
Have tried the Top Tier rated brands including the vaunted Chevron and car ran noticeably worse so I believe that what the sign says isn't always what you're getting...........
Other than that car runs great, plugs look fine, not using oil.
Have tried the Top Tier rated brands including the vaunted Chevron and car ran noticeably worse so I believe that what the sign says isn't always what you're getting...........
Le Mans Master
Joined: Dec 2006
Posts: 7,251
Likes: 16
From: Phoenix Arizona
Le Mans Master
Joined: Dec 2006
Posts: 7,251
Likes: 16
From: Phoenix Arizona