Today (Saturday) I put 93 octane in. It has not pinged so far. I cannot afford to keep running 93 octane though and shouldn't have to after 3 years of 87 octane.
If it is a bad gas problem.....I am testing this theory by switching brands of gas (I usually get Exxon) and second, I am wondering if is happening from switching to/from oxygenated gas that is used in New Joisey. I believe the state usually changes in April/May timeframe.

Of not the bad gas theory, I will then look into the other suggestions.

Stone

Stone,

You may want to check your timing. I just had mine checked and the timing was way too advanced (by about 4 degrees). Once the timing was adjusted to factory spec, the pinging was almost completely gone. I still get a bit of pinging under really heavy acceleration, but it's not as much as before.

I agree, buying premium fuel just to get rid of pinging is too expensive. Give the timing thing a try. It just might do the trick.

Thanks XCFreak. I will look into this if it ever stops raining here. It cannot hurt to check it.
For now, I still have the 93 octane in and I have had no pinging yet.

How much did your dealer charge to adjust your timing?

Stone

Well, I just told them my car has been pinging when climbing uphills or during hard acceleration and I said that they better check the timing or my engine is gonnna wear out prematurely. So they checked it for free. My dealer is pretty cool. You just gotta make it sound like it's a car design problem and not due to everyday use. I think the timing issue is well known with Nissan so I'm sure they'll look at it for free. The mechanic that fixed the timing said it happens to a lot of Nissans and that the computer mucks with the timing. Use that angle and they'll most likely fix it for you free of charge. Good luck.

I always use Chevron Techron fuel additive at least twice per year, and also 2 tankfulls back to back (2 bottles)
This stuff enjoys the best reputation of any fuel additive for cleaning carbon deposits from valves, and pistons. Here is a copy of a few Q&A's from the Chevron web site on why and how it works.
I have never had a problem with pinging, and stick to this preventive maintenance schedule.

Pilot


The principal difference between Techron® and Techron® Concentrate is additive concentration and rate of deposit clean-up. At the concentration present in Chevron gasolines, Techron® over many tankfuls will help clean up deposits on intake valves without contributing to combustion chamber deposits. So, over time, Chevron gasolines with Techron® are able to reduce or eliminate deposit-related hesitation and stumbling during acceleration caused by deposits. A bottle of Techron® Concentrate, when added to gasoline according to the label instructions, results in an additive concentration roughly 10 times stronger than the dose in our gasolines. This mega-dose of Techron® provides a much quicker clean up of intake valve deposits left by lower quality gasolines. In addition, the high concentration of Techron® reduces combustion chamber deposits, which can help reduce or eliminate deposit-related engine knock and run-on.

Do I need to use Techron® Concentrate if I buy only Chevron gasoline?

If you're a loyal buyer of exclusively Chevron gasolines, your car very likely is delivering its best possible performance and operating at its lowest possible emissions. A bottle of Techron® Concentrate, therefore, is not likely to provide any benefits. However, if you sometimes purchase a lower quality gasoline, you should try Techron® Concentrate to quickly restore performance lost due to deposit accumulation.

Is Techron® just a more diluted version of Techron® Concentrate?
Not precisely. While both are polyether amines of very similar structure, each is optimized for its particular application. Techron® cleans engines and keeps them clean through regular use of a lower additive dose, while Techron® Concentrate provides a quicker clean-up through intermittent use of a higher additive dose.>

http://www.chevron.com/prodserv/fuels/gas_qanda/tech_con.shtml