You're engine is knocking at WOT. That "pinging" you are hearing is mild detonating. Bad detonation sounds like a loud "knock". If you let it keep going, the "pinging" you are hearing will turn into "knocking"...if the engine lasts that long.

Your stock PCM will pull timing when it detects detonation to eliminate it. However, this is limited. The stock PCM can only pull up to 15* of timing to combat detonation. This timing being pulled is called "knock retard" and is usually referred to as "KR".

You need to perform a full tune up on your car. Most likely, you're pinging is caused by a combination of factors:
-Malfunctioning sensors (dirty MAF sensor, fouled O2 sensor)
-Clogged fuel filter/injectors, poor fuel pressure
-Worn out spark plugs with huge gaps
-Carbon build up in your cylinders

You should perform a full tune up ASAP, including replacing your front O2 sensor, fuel filter, and performing a top end clean with SeaFoam in addition to traditional tune up items (plugs, wires, etc). I bet your pinging goes away after this. The car will feel alot stronger, too.

 

IMO, you really need to get a scan tool on that thing to find out what is going on- look at your KR value, fuel trims- etc etc and try and track down what problem/problems the car is having.

Have you been keeping up with manufacturer recommended maintenance?

 

Thanks Shawn and Bumpin for all your help. I have been pretty good about keeping up on maintence on the car. I'm not too sure about the previous owner but there is a huge stack of repair records that he sold the car with and I should probably go through them to guage what exactly has been done. I do have and OBDII scanner but I'm not sure if I can see the KR value on it. It is fairly fancy and not one of the cheapy ones.
With poor fuel pressure, would the fuel pressure regulator be a good culprit? Every once in a while the car will not start unless I press on the accelerator a little. Sound like the pressure regulator or should there be CEL for that? I know the O2 sensors are good because I replaced both of them when I changed my cat. I just did the LIM/UIM gaskets and looked over the injectors, seals, and lines and it all looked good. I know that looking at an injector does not tell you if it is clogged though.
I bet the plugs could be replaced too.
Let me know if you know of any common symptoms of a bad fuel pressure regulator.
And again, thanks for all the help

 

Hard to say if it would throw a code- it won't throw one directly, it would be something along the lines of a lean code.

Really though, don't just go replacing stuff that might be bad- your best bet is to get a hold of a scan tool (and maybe a fuel pressure tester) and start actually checking the items.

No sense in replacing stuff because it might be the culprit- make sure you know the part is bad.

 

A way to check the FPR is to remove the vacuum line and smell it. If it smells like gas, your FPR is probably bad.

 

I think it's always a good idea to replace your fuel filter if you have high miles. I'd do this regardless of whether or not it's the root cause of your issue. I change mine yearly. You'd be amazed in the difference it makes in before after fuel pressure/narrowband values, even after just one year of being on the car.

 

Thanks to all for the replies. I think I will start with the fuel filter, I bet it needs to be replaced anyway and check the vaccum line for fuel smell. I take it this vaccum line on the fuel pressure regulator should be pretty easily accesible?
Thanks to all once again for all the great tips and advice.

 

I'm sure you have an L36, so I'm not 100% on where the FPR or what it's like, but if it's like my L67, there should be a vacuum line leading to it and it pulls right off. Should have a rubber connector for the vac line to meet the FPR.

 

Thanks Again!