Diabolical!

Yes! Especially if you only hear it under load. Baby that car to a tuner.

Jersey Stang

YIKES! i've been running like this for 2,000 miles and a couple 1/4 mile passes. could it be anything else or is it definitely running lean??

VistaGT

I would think that if your motor is okay now then it should be fine, I think the damage is an on-the-spot thing as in if detonation destroyed your motor you'd know about it and the motor would show the signs now.

Again, with my car I had a lot of pinging and to try and narrow the sound down I did probably 20 redline pulls over a month. Yea it sucks knowing it was detonation but the motor runs perfectly now and still pulls smooth and strong. If the motor was ****ed, it wouldn't run as it does now.

For you I think you're fine but don't get on it any more lol.....detonation is 10X worse for F/I cars......

candymanjl

the sound would most likely be continuous. it wouldn't really be one loud sound, it would be a continuous metal on metal sound.

if you listen to loud injectors at idle that's a fairly similar sound to pinging.

as far as adding the LT's without changing the tune you may have changed the AF ratio. did the boost change after the LT's? also you may have an exhaust leak, I've heard that's a common problem with LT's.

Jersey Stang

it sounds very similar to injectors, just not as loud. I didn't know an exhaust leak can cause pinging. My boost levels haven't changed after the install. But, I noticed my A/F spikes to 16.5 or higher sometimes, but then goes right back to 14.7 and down to 10 when I lift the throttle. Would anyone recommend playing with the fuel trim to stop the pinging?
Thanks for all the help and sorry to Blacksmoke for the hi-jacking.

candymanjl

I didn't mean that the exhaust leak would cause pinging, just that it would make noise.

going as lean as 15-16:1 in light loads isn't uncommon or something to really worry about as long as it corrects like you mentioned.

moosestang

I had pinging with my brenspeed 93oct tune. It was quite obvious under hard acceleration. The motor should not ping at idle or even free revving. I went on to supercharge my pinging motor and it's been fine ever since.

Pinging is an erratic, metallic ratting sound that can be confused with a dash rattle or like someone said, a rattle from the shifter. I thought mine was the shifter at first.

VistaGT

How long was your car pinging for? That's what I wonder - with my car pinging for so long is it okay now and for the long run

Simon1

Under WOT your car will not send a code if it starts to run lean. If your short term fuel trims are off, then it would throw a code.

Simon1

This is how it had been desc ribed to me by differtent tuners

The reason why you car will not throw a code under load is because the O2 sensors are basically not working under WOT. Idle fuel trims are determined based off of cammands given to the computer from data recieved from the O2 sensors. If the sensor detects a rich or lean condition at idle and under normal driving it will try and adjust the trim to make the car run right. It can only do that if your trims are just a little off. The tuner corrects this by adding or subtracting fuel under different sections of the cars parameters in regards to idle all the way thru 5th gear.

To best describe what detonation is, takes a glass jar and put marbles in it. Shake it around. That's what detonation sounds like.

It is usually caused by:

Too much timing

Too lean

Vaccum leak

Bad fuel

Your AF readings you decribed below are very very slightly off what a really good tune would be, but not anywhere to be concerned most likely.

If you beleive you are getting detonation you can subtract 2 degrees of timing in your hand held tuner and drive the car. If it continues you can take 3-4 more degrees out and see if goes away. If it never goes way than it's probably not detonation.