glowz825

I have noticed a little bit of pinging going on under light to moderate acceleration . I use the highest grade gas out here which happens to be 91 oct.Will octane booster help or is this a serious issue that the dealer should look at. I drive a 06-it has about 2800 miles...Thanks for your in put

ZCARBANDIT

iTrader: (73)

Don't run ocatne boost. It is a waste of money. There was a thread similar to this in another part of this site. May have been under the modifications section cant remember.

glowz825

thanks I just looked in the engine section and there is 2 pages of input about pinging.Looks like its just the way it is

rfinkle2

i have an 06 too, and run nothing but 93 octane. the dealer retarded my timing 2 degrees, and it still pings in the heat...


its hard to get anyone to reply on the boards about this.

Zreign

This is a common issue but can easily be tuned out.

cox

iTrader: (3)

+1 with my 35th anniversary...

newzee

Ive got an 06 and I noticed the ping after I broke it in and was starting to accelerate harder. The manual does say something about it. Its not the valves its the ignition timing. I had the dealership advance my timing 2 degrees and that helped a little but it still does it after my daily drive and its hot. It annoys the **** out of me but I dont think that it causes any damage. Regardless of the timing advance I think eventually the ECU will retard it under any highway or light driving anyhow. Ive had a little success by accelerating hard and getting the throttle wide open since that will force the ECU to advance the timing but having to do that at least once a day gets old even though its fun. Id like to know what mods might make this stop. I haven't done anything to it yet cause the money is a little tight right now but I do want the mrev2 and plennum spacer. I wish I could do something to the ECU without having to get a piggyback unit. Any thoughts? Thanks

TheProfessional

iTrader: (14)

I have the same problem under medium acceleration, noticably between 1500 and 2000rpms in 3rd.

Q45tech

Remember the marketing sticker on pumps is there so you can tell the difference between grades not necessarily to tell the absolute truth!

After all the number stays the same yet each day the octane varies somewhat depending on batch from tank farm and refinery.

R+M/2 = posted number [sometimes]...........the computers at the refinery blend and round up to minimize costs.

R octane is much less expensive to create and M octane costs 2.5 to 4 times as much as R octane points.

Unfortunately M octane is what needs to be high to avoid accelerator tip in KNOCK.


Hopefully you can see that a much much higher R octane can average out to a decent blended number yet you still have knock with Premium.

http://en.wikipedia.org/wiki/Octane_rating

Try blending 50/50 premium with and premium without ethanol and see if. problem goes away.

Sasha350

I have the same pinging problem with my 06 MT.
It is not the gas as i never put anything other then 93 gas and I had this since i got the car 8 months ago. Under acceleration and only after the car gets hot from driving. I do not have this problem early mornings when its still cool.

Mike@Altered

iTrader: (5)

The 06's run a decent amount of timing compared to some of the earlier models. We've seen this pinging also and it is a concern we and a few of the Turbo Kit manufacturers have collaborated on recently.

It seems to come from a combination of factory timing and lean running between 1,500 and 3,000rpm on the 06's. My best recommendation is to run the highest octane available!

Hope this helps,

Sasha350

Well, other than that recomendation, what else can be done since there is nothing higher then 93 gas where i live.

Mike@Altered

iTrader: (5)

You can try an ECU Flash to update the fuel/timing or a good piggy-back fuel and timing computer. The factory ECU may correct over the piggy-back at low rpms though.

Hope this helps,

06blueZ

iTrader: (10)

06 revup here with the same pinging issue. I have just been noticing this recently, and thought it was a bad tank of gas, or even that I forgot once and put in regular, but nope.

Arn't there multiple knock sensors on these motors? I would have thought that they would be able to detect this and compensate, but maybe the factory fuel curve is maxed out alreasy when a knock is detected?

Damn, that is pretty bad. I am used to it in my 13 year old beater truck, but not the Z!!!

Mike@Altered

iTrader: (5)

I have a customer scheduled with an 06' so that we can better pinpoint this issue and see what I can do to reprogram the factory ECU to get you guys around it.

I'll keep you posted -- give us a week or two!

Q45tech

The fuels used in Japan to derive the SOFTWARE [ignition advance] were ARE superior [in MOTOR OCTANE NUMBERS] to those currently provided in US. Simple as that. Even domestics have Chevron/others supply them with SPECIAL TO SPEC PREMIUM for use in developmental labs/dynos.

Just because a pump says 91 or 93 doesn't mean it is that high. THERE are no legal requirements that the pump label be accurate! No state tests other than to prove that midrange is higher than regular and premium is higher than midgrade............to avoid fraud charges...................this is done via a density test not an octane test.
It is not Nissan's fault that the refiners are weakening their product to keep prices down.

Q45tech

FCC Octane MON Versus RON

Significance of RON and MON

For clarity it is useful to provide a general overview of an octane number. An octane number is a quantitative, but imprecise measure of the maximum compression ratio at which a particular fuel can be utilized in an engine without some of the fuel /air mixture "knocking" or self igniting. This self ignition of the air/fuel mixture in the cylinder results in a loss of peak power. Directionally as the compression ratio of the engine increases so does the required octane number of the gasoline if engine knocking is to be avoided.

The performance of an engine is dependent upon many factors, one of which is the severity of operation. Accordingly the performance of a fuel is also dependent upon engine severity. To account for differences in the performance quality of a fuel two engine octane numbers are routinely used. Thc Research Octane Number (RON, or F1) simulates fuel performance under low severity engine operation. The Motor Octane Number (MON, or F2) simulates more severe operation that might be incurred at high speed or high load. In practice the octane of a gasoline is reported as the average of RON and MON or R+M/2.

Classically, both numbers are measured with a standardized single cylinder, variable compression ratio engine. For both RON and MON, the engine is operated at a constant speed (RPM's) and the compression ratio is increased until the onset of knocking. For RON engine speed is set at 600 rpm and MON is at 900 rpm.

MON and RON Depend on Gasoline Composition

The octane number measured is not an absolute number but rather a relative value based on accepted standards. By definition, n-heptane has an octane number (RON and MON) of 0, while iso-octane (2,2,4-trimethyl pentane) is 100. Linear combinations of these two components are used to measure the octane number of a particular fuel. A 90%/10% blend of iso-octane/n-heptane has an octane value of 90. Any fuel knocking at the same compression ratio as this mixture is said to have an octane number of 90.

In general, RON values are never less than MON, although exceptions to this rule exist. For pure compounds the differences between RON and MON range from 0 to more than 15 numbers. Typical values for gasoline range hydrocarbons having boiling points between 30° and 350° F go from less than 0 to greater than 100 with the extreme values being generated by extrapolation. Table 1 summarizes actual RON and MON values for a variety of pure hydrocarbons.

In practice octane numbers do not blend linearly. To accommodate this, complex blending calculations employing blending octane numbers as opposed to the values for pure hydrocarbons are routinely employed. There is no universal blending program used industry wide. In fact, for a given oil company, blending calculations that are refinery specific are not uncommon. As an improvement over octane numbers of pure compounds, there are tabulations of blending octane numbers for both RON and MON. Summarized in Table 1, these numbers are measured by blending 20 vol.% of the specific hydrocarbon in 80 vol.% of a 60/40 iso-octane/n-heptane mixture. Although still not exactly indicative of the actual blending octane number for a specific gasoline composition, the blending octane numbers are more representative. In general, the blending octane numbers are greater than the corresponding pure octane number.



Octane in FCC Gasoline

Discussions of the source of octane in FCC gasoline are numerous. For the most part these discussions focus on RON and avoid the discussion of MON. For RON it is well known that increasing the aromatic, iso-/normal ratio and olefin content of gasoline results in significant increases in octane. Current catalyst technology requires that the hydrogen transfer activity of the catalyst be low if RON is to be increased. Most FCC octane catalysts make RON by increasing the olefin content of the gasoline rather than making aromatics. The use of Z-100™ catalyst for increasing RON relies on cracking of low octane N-paraffins to generate olefins and concentrate the aromatic content. In fact it can be said that Z-100™ catalyst does not make gasoline octane, but rather it concentrates it. A source of increased aromatic content can come from selective bottoms cracking. Selective bottoms cracking implies that substituted aromatic hydrocarbons boiling outside the gasoline range (>400°F) have their boiling point reduced to below 400°F by selective cracking of large substituent side chains. These can be either long chain paraffins or naphthenic rings. The saturated substituent will crack while the aromatic core cannot. Bottoms cracking of this type may most likely be achieved through improved understanding of the role of the matrix.

Improving the RON of FCC gasoline as discussed is for the most part well understood. The same cannot be said for MON. Although it is true that increasing the RON of gasoline does increase its MON, the incremental increase in MON is typically only 33-50% of the RON. Referring to Table 1, MON values (either actual or blending) are always less than RON except for highly branched paraffins. Increasing the weight fraction of isoparaffins in the gasoline should result in an increased MON/RON ratio although overall R+M/2 could in fact decrease. This is due to the fact that although isoparaffins have higher MON values than RON, their absolute values are generally less than their olefin counterparts.

Another approach to increase the MON / RON ratio of gasoline may result from increasing the weight fraction of those hydrocarbons having blending MON's nearly equivalent to the blending RON's. Examples include propyl or isopropyl-benzene, C-5 and substituted C-5 naphthenes and highly branched olefins like 4-methyl 2 pentene. The ability to selectively increase the concentration of these hydrocarbons may be more a feedstock property than anything that current catalyst technology can do.

If motor octane is to be increased to a greater extent than research octane it appears that the specific hydrocarbon types must be selectively produced or concentrated. Directionally, the degree of highly branched isomers, either paraffinic or olefinic, must be increased with emphasis on the degree of internal branching. Although aromatics have a large effect on both RON and MON, alkylbenzenes such as propyl or isopropyl benzene may effect MON to a greater extent than RON. To fully understand the factors effecting MON, detailed chemical characterizations of a variety of gasolines should be studied.

Consar

I've also noticed pinging as you described on my 35th Anniv. We get 98 and 100 RON Fuel here in Australia and it does vary in quality. The service manual states that using a Cold Type saprk plug should fix this, although I'm yet to try it, my car is still with Nissan, one month on.... Here's an extract from the service manual, has anyone tried this to resolve the pinging ?

Use standard type spark plug for normal condition.
Hot type spark plug is suitable when fouling occurs with standard type spark plug under conditions such as:

Frequent engine starts

Low ambient temperatures
Cold type spark plug is suitable when spark plug knock occurs with standard type spark plug under conditions
such as:

Extended highway driving

Frequent high engine revolution

Make NGK
Standard type PLFR5A-11
Hot type PLFR4A-11
Cold type PLFR6A-11

Q45tech

We get 98 and 100 RON Fuel here in Australia

US premium are the same 98-100 RON is cheap to make. The MON of such fuels is usually 75-81.5 when it should be at least 85 to avoid knock on a high compression engine.

The 75 MON garbage is made to blend with ETHANOL where it can become 87 average Regular.......the worked ok when MTBE was used due to MTBE's HIGHER MON NUMBER..........Ethanol has a LOWER MON number.

A good test is to find some 93 non ethanol and mix with 50/50 Ethanolized 93 Premium...........this gets the best of both worlds and halves the mpg penalty from the ethanol. A couple of gallons on MTBE or Toluene/m Xylene would be a better solution but cost more.

"Xylene is one of the top 30 chemicals produced in the United States in terms of volume. It is used as a solvent (a liquid that can dissolve other substances) in the printing, rubber, and leather industries. Along with other solvents, xylene is also used as a cleaning agent, a thinner for paint, and in varnishes. It is found in small amounts in airplane fuel and gasoline."

In the EU especially Germany they have MINIMUM MON specifications.

RebelinRI

iTrader: (22)

I thought this would never end!!!! Thank you Consar!!! Want to get rid of that stupid ping???? EASY. Get a one step colder IRIDIUM plug. It's that easy! Platinum is excellent for spark ignition, but sometimes too good. This is exactly why Nissan and others use them. At times when other plugs will foul these will keep sparking right along. Platinum is good also for creating spark in some undesirable condition which also helps them. Ping is basically pre-ignition. You can also get a good copper based plug but make sure it's one step colder. I'm very curious to see what Mike will find out as far as from the ecu's point of view. I had this ping and solved it with NGK's Iridium plug #LFR6AIX-11. Someone else try this and respond to the thread. My dealer at first had me change gas stations but always using premium gas. As Q tried to say the mixture will differ but trying station to station over 2 a month period did nothing for me. Hope it helps and don't forget to post Mike please!

By the way guys the octane # indicates resistance to pre-ignite, not being a more powerful fuel. That sentence sounds goofy but I hope you understand without the big long speech.