I have a 2003 Z06 with NO mods and 29,000 miles on it. I de-carbonized it with a whole can of SEA FOAM and it still pings. It pings between 4000 and 5000 rpm on 91 octane gas. Anyone else hear of this or have the same problem?

 

Sounds like cheap gas, or your getting cheap gas and paying for mid range. If you engine is running hotter than normal, it will ping also.

 

Yea, try a different brand like Shell or Chevron. Assuming the car hasn't been driven like crazy (i.e. needing a tune-up), the problem sounds like gas.

 

I know of others that have had pinging issues. Some were able to correct it by changing fuel brands and for some this did not help. A fuel octane booster like Torco well most likely correct the problem but you are adding a continuous cost every time you fill up. (Sorry Joel) With a custom tune the tuner can correct it permanently.

 

Yes, I know for a fact that Torco works! I ran a 2:10 on 13A CW at Buttonwillow on Torco I also know I friend (Dirty Howie) that had a pinging problem and had his car re-tuned. They took out 1 degree of timing and he lost 10 HP I'm trying to figure out how to stop the pinging with out having to re-tune and loose any power.

 

I would buy good gas, and run a couple tanks through with a good injector cleaner. It sometimes takes several applications. I would use techron or 44K (BG product). I would also take it to a shop that sells BG (most dealers) and have them do the 3 stage fuel induction service. And beat the crap out of it ! Extended high rpm's clean carbon best. Make sure it's full of Mobil 1 and don't blow the engine.
Good Luck !

 

I have a 2001 Z06, stock with the exception of air box. My car normally gets 93 octane and has no fuss. I took it on a 5500 mile road trip of the southwest and as soon as I hit the 91 octane premium, my Z would ping like crazy under part and full throttle. This was independent of brand of gasoline, on at least a dozen tankfuls of 91 octane gasoline. GM's manual says 91 octane is fine, but my car does not like it at all. It has been to two different dealers, had two batches of the GM upper cylinder cleaner, and had the ECM reprogrammed at least twice, to no avail. GM says that my car is OK and is completely normal.

I know plenty of Z06 owners who do not have my experience with pinging.

 

Yeah, all we get here in Arizona is 91. Use to get 93 maybe 5 years ago. My stock '01 is fine with it. Does the LS6 have a knock sensor? I know the older GM motors do, and if they fail, the computer will advance the timing and cause the ping.

 

(I took it on a 5500 mile road trip of the southwest and as soon as I hit the 91 octane premium,)


A lot of people that are driving in the southwest are having the same problems, because they're using more than 10% ethanol in their mix now. Some stations are 85% ethanol. What it's doing is creating a pinging or clogging the injectors. Be careful if you travel outside the eastcoast. Check the % of ethanol before filling up. Our cars are only able to accept 10%. On the eastcoast, Sunoco, Mobil, Shell, American are adding 10% ethanol in their gas. The ones that are not using Ethanol are Hess, BP, and Texaco.

 

Sounds definitely like the fuel. The PCM should adjust for 91 octane, but you also have +10% ethynol which wasn't taken into account in
2003.
The other factors are oil in the intake. Get an oil catch can. Oil in the intake lowers your initial octane number. The PCV system is a poor design, and using 91 is cutting it close. I run a 160 degree thermostat along with my high compression. It may be a good idea if you want to run 91 with the other factors coming into play. Sea Foam is a great product, but without the catch can, you will continue to run with the oil consumption through the intake problem. I would eliminate the oil issue first, then an application of Sea Foam will be more effective to keep the valves, combustion chambers and intake ports clean. I use 1/3 of a can of Sea Foam every 2 oil changes, with 2/3 going into the gas tank to be distrubuted through the injectors.

 

I don't understand the catch can. I've seen them adevertised regularly, but thought that it was for track use.

What does the catch can do that isn't provided for on a stock engine?
Why does "oil in the intake" lower your effective octane?
Why is there oil in the intake anyhow?

Inquiring minds want to know...
thanks,
mk

 

Good question zulatr. The design of the PCV valve (system) is poor. What ends up happening is; at idle under high vacuum, oil is drawn up from the engine (crankcase) into the PCV valve. The oil passes through the valve directly into the intake and contaminates the fuel entering the combustion chambers thus lowering the octane content, but this isn't only oil entering. When you start up your car, before the oil and water temperature reach 140 degrees, there is condensing going on inside the engine. You see water dripping from the exhaust tail pipe, but you also have moisture in the oil. The oil has to stay hot for a long time to burn off the excessive moisture. The octane content of oil is very low compared to gasoline which has been refined. (The variation in aromatics content as well as the variation in the content of normal paraffins, branched paraffins, cyclopentanes, and cyclohexanes is dependent upon the characteristics of the petroleum feedstock, and influence the octane number of the gasoline.) Mixing oil with gas will lower the gasoline initial octane content (the ability to knock) when the two are mixed and even have a tendency to detonate. The solution to this problem is to install an oil/water catch can inline before the PCV valve. As oil/water is being drawn up through the valley tube, the catch can traps the oil/water before it reaches the PCV valve and fills up the can with oil/water, instead of letting it pass through the PCV valve directly into the intake. This keeps the oil/water sludge from attaching itself to the intake ports, valves and combustion chambers. I found this to be the case during my head swap. It took me alot of time to figure out the cause and solution to this problem, but I think I have it beat without question. I've had to incorporate the catch can into my regular maintenece, but it is a small price to pay to have no build up and an excellent and efficient running engine. As said before, I also use Sea Foam to ensure it all stays sludge free every 2 oil changes, added through the intake and fuel injection systems.

 

I drive the hell out my car on Chevron 91 octane and its never pinged, even on 100 degree days. Some cars do, some dont. Go figure...

 

Try it with BP Premium, BP is the only one that supplies its station from its refineries.

 

BP and Amoco I've heard are the better gas, but that is just my.02 and I have not had any issues with any of the 5 vehicles that I have and fuel up, all with high test.

 

I've run BP/AMOCO regular with no issues. Its interesting that the octance ratings state 87, 89 & 91/93 are the minumim.