Ping
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Joined: Oct 2005
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From: CT
Ping
I experiencing a definite pre-ignition under very specific conditions. It occurs at about 1300rpm and part-throttle. It's typically jsut a handful of pings as it goes through this RPM range, but I can often make it do it a few times in a row.
Thoughts?
Mike
Thoughts?
Mike
Le Mans Master
Joined: Aug 2003
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From: American Canyon Lethal Injection
Lots of causes for engine ping.
1. Grade of gas being used.
2. Carbon buildup.
3. Oil getting into the intake.
4. Tuneup needed.
To name a few...
Sleeper
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From: CT
I can get it to do it in 1st, 2nd or 3rd gear if I ge the rpm's to about 1200 & then apply about 1/4 throttle. There is preignition as it goes through 1300rpm.
Car is a stick. '99 About 55Kmiles
Car is a stick. '99 About 55Kmiles
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Has it had the plugs and wires changed? Try running Sea Foam through it to clean carbon build up.
Put in a Sea Foam search and you'll find out how to use it and how it may help your problem.
Put in a Sea Foam search and you'll find out how to use it and how it may help your problem.
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Le Mans Master
Joined: Feb 2006
Posts: 5,267
Likes: 40
From: Phoenix AZ
Things it could be:
Bad gas (not enough octane)
Carbon build up on pistons
Aftermarket boltons without tune
Driving in hot weather in too tall of a gear (lugging motor)
Engine running too hot
Bad gas (not enough octane)
Carbon build up on pistons
Aftermarket boltons without tune
Driving in hot weather in too tall of a gear (lugging motor)
Engine running too hot
Pro
Joined: May 2004
Posts: 551
Likes: 19
From: Morgantown WV
This probably has nothing to do with your engine but I thought I'd post it for info only. After I did my mods and got the car tuned the engine sounded like it was experiencing pre-ignition from 4500 - 6000K. This was affected by density altitude. On a cold day, no noise, on a hot humid day it sounded exactly like spark knock while under load. The tuner confirmed there was no pre-ignition / detonation while the car was on the Dyno. It turned out to be Coil Dwell. The ignition was actually sparking / firing out the exhaust due to the combination of compression and valve overlap. This was adjusted and the noise went away with no loss of power. I don't recall ever reading any posts on coil dwell so here it is for what it's worth..
Le Mans Master
Joined: Feb 2006
Posts: 5,488
Likes: 4
From: USA
This probably has nothing to do with your engine but I thought I'd post it for info only. After I did my mods and got the car tuned the engine sounded like it was experiencing pre-ignition from 4500 - 6000K. This was affected by density altitude. On a cold day, no noise, on a hot humid day it sounded exactly like spark knock while under load. The tuner confirmed there was no pre-ignition / detonation while the car was on the Dyno. It turned out to be Coil Dwell. The ignition was actually sparking / firing out the exhaust due to the combination of compression and valve overlap. This was adjusted and the noise went away with no loss of power. I don't recall ever reading any posts on coil dwell so here it is for what it's worth..
....hmmmm interesting. I thought I'd heard it all on this forum. I learn something new everyday here.
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Joined: Oct 2005
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From: CT
From this & other threads it seems like there are 3 likely items;
Air Temp Sensor
Plugs
Carbon
I just hooked up an OBD computer & it shows a reasonable reading on the Intake Air Temp, so I think I can rule that one out. My next move it to change plugs since the car has 55K on these plugs anyway.
If that does not cure it, I'll do the Sea Foam trick.
Mike
Air Temp Sensor
Plugs
Carbon
I just hooked up an OBD computer & it shows a reasonable reading on the Intake Air Temp, so I think I can rule that one out. My next move it to change plugs since the car has 55K on these plugs anyway.
If that does not cure it, I'll do the Sea Foam trick.
Mike
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
My '99 has been pinging for a long while now. I've replaced the IAT sensor, used Seafoam, always use 91 or higher octane, tuned it via a professional tuner, replaced plugs and so on...nothing seems to stop it. I have noticed that it does not ping when the engine starts up cold and not until the oil temp gets up to a normal range and then it will start pinging. One other thing I've noticed is the color of the exhaust pipe outlets. The right side is lighter or leaner than the left side. That makes me contemplate the O2 sensors on the right side may be contaminated with carbon therefore incorrectly telling the pcm to lean it out, therefore pinging. Anyone have thoughts along this line or other?
Melting Slicks
Joined: May 2006
Posts: 2,936
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From: Westchester County New York
Racer
Joined: Sep 2003
Posts: 347
Likes: 6
From: Midwest
Regardless of the "cause", what I would like to know, is how come the supposed "knock-sensors" do not detect this ping and retard the timing accordingly as it is designed to do?
I read about this pinging problem all the time here....mine even "pings" frequently under such a load as when accelerating up from around 30 mph but not so the tranny backshifts.
Nothing I have ever done has gotten rid of it. The dealers says it's "normal". Pre-igition is considered normal?
Last edited by TuffShift; Aug 19, 2007 at 05:20 PM.
Melting Slicks
Joined: May 2006
Posts: 2,936
Likes: 260
From: Westchester County New York
Regardless of the "cause", what I would like to know, is how come the suppose "knock-sensors" do not detect this ping and retard the timing accordingly as it is designed to do?
I read about this pinging problem all the time here....mine even "pings" frequently under such a load as when accelerating up from around 30 mph but not so the tranny backshifts.
Nothing I have ever done has gotten rid of it. The dealers says it's "normal". Pre-igition is considered normal?
I read about this pinging problem all the time here....mine even "pings" frequently under such a load as when accelerating up from around 30 mph but not so the tranny backshifts.
Nothing I have ever done has gotten rid of it. The dealers says it's "normal". Pre-igition is considered normal?
I guess it has to do with the knock sensors kicking in only after its either a more pronounced ping or its for a longer period of time...I have the ping every now and then but its just for a fleeting moment,,mostly when in 6th at highway speeds and stepping on it...quite frankly, I prob should be in 5th gear...when I am at the same speeds it doesnt ping in 5th...but it is quite frustrating...
Le Mans Master
Joined: Feb 2006
Posts: 5,267
Likes: 40
From: Phoenix AZ
You guys probably just need to richen it up a little. Thats what I had to do to mine. It would start to ping right at 4000 rpms and up. I got a predator and just custom tuned it with more fuel till it went away.