Wyze

Pulled up to the gas station today and some guy says " nice car but why is it pinging"!!!!!!

I'm confused because I thought the noise I was hearing was coming from my converter not my engine!!!
The reason I say this is I can hear it when in gear but not in N!!!
It sounds like a thumping!!!!!


Thanks Drew!!!

jaunty75

"Pinging" is engine knock, and you would generally be more likely to hear it under load than sitting at a light, and having the car in neutral puts even less load on the engine, so you might not hear it at all.

If you're not sure that this guy knew what he was talking about, and if you're not sure yourself what engine knock sounds like, you might want to take it to a mechanic and have him listen to the engine.

Slight, occasional pinging under acceleration is often not a problem, but regular pinging is. Pinging is due to the spark plug firing too early, before the piston has reached the top of its stroke, so the piston rattles around a bit in the cylinder. This robs the engine of power and can cause overheating among many other problems. It can be caused by incorrect ignition timing, carbon buildup in the cylinder causing reduced volume and thus increased compression, which can cause the fuel/air mixture to pre-ignite, or by poor engine cooling causing localized hot spots that ignite the fuel/air mixture before its supposed to be ignited. I'm sure there are other causes as well.

You should track this down to first make sure that it really is engine knock you're hearing, and, second, if it is, have the problem dealt with.

leftcoast carl

the "pinging" he was probably referring to is also known as detonation.several things will cause it,but having your timing advanced too far,or running a poor quality fuel in a high-compression engine are the two most common causes.detonation is REALLY tough on a motor,because the fuel is igniting too early and the explosion in the combustion chamber is putting unwanted additional stress on the pistons,rods,and crankshaft.DO NOT IGNORE THIS SYMPTOM! if you don't know how to identify or correct the problem yourself,get some help NOW.
leftcoast carl.

leftcoast carl

oh yeah.....it won't ping in neutral,because there is no load on the engine when idling in neutral........put it under load(like pulling a BIG hill,or heavy acceleration) and the pinging will rear it's ugly head.
L.C.C.

jaunty75

Yes, I'd forgotten to mention this, and it's a very good point. If your car requires premium fuel, and you're putting in regular, that could cause it.

w-30dreamin

I don't know about 68 but my 71 emissions tag for a 350-4 barrel says "fuel requirement use 91 octane or higher". And my car does run crappy with 87.

oldsmobum

Some people compare "pinging" to the sound rocks in a coke can would make... Its not very thump-like. If you happen to play guitar, it sounds just like when you shake an unplugged amplifier with spring reverb.
Does it happen in gear when you're stopped at a light? How heavy is the thumping? Like hammer against the tranny tunnel thump?

Wyze

I don't know!!! I keep getting buildup on my front 2 driverside plugs!!! I was checking them and noticed 1 was a R45 which is wrong!! All the others are R45S!! Could this have been causing the pinging???? My converter shot craps on me, so I'm guessing maybe that's what he heard???
I don't hear any knock from my engine but when I mash out & my RPMs are up it does sound scary!!! Smh

I know my engine isn't right so I'm gonna have it looked at by a pro after I do a couple more things!!!!!