Wired 24/7

iTrader: (2)

black sunshine, did you ever reset your ECU? any mods?

What year is your car?

You made me curious now.

If you are very concerned and want to drive out to where I'm located, I can use the cipher on your car and we can retard the timing by up to 2 degrees and you can see if that helps. Or even datalog air/fuel if you have the factory widebands.

Are you buying gas at the same location all the time?

PS I'm not confusing pre-ignition with detonation/knock/spark knock... as you seem to already know, pre-ignition is the more dangerous condition and that should be prevented by the ECU at all costs. Sounds like you're talking about spark knock which is more likely given that the timing is often set very close to the knock point under load...

by the way +1 on everything 97supratt said, oil in the combustion chamber can contribute to this condition too. You don't seem to be burning too much oil I hope?

hiz-n-herz

iTrader: (11)

2.5k to 3.5k rpms, under load, but only for a second or two. Still disappointing though.

I really wish I had waited for the 07 or whenever the new engine is supposed to come out. Someone posted a link to a nissan presentation for the new engine and it said coolant has been rerouted through the block (or was it the head?) to aid cooling and there are two knock sensors - Coolant routing and knock sensors are said to help with with pinging. The presentation also admited to a 5.8 sec 0-60 time with the 06 Z. I don't think I've seen that slow of a time posted anywhere before. I thought my 10 year old, 220,000 mile M3 felt faster... and it NEVER pinged.

trey.hutcheson

iTrader: (2)

I just picked up 6 1-step colder NGK irridium plugs. The local napa store wanted over $19 per, but the manager(a lose-acquaintance) gave them to me for $5 each.

I hope to put them on this weekend. I got these because I've been experiencing what I consider excessive ping as well, NA(all 93).

97supratt

iTrader: (61)

That should help a bit.

Black_Sunshine

2006, 10,500 miles. It's done since the day I drove it off the lot. That's a very generous offer, I suppose it depends on where you are. I've wondered more than once if only 2 degrees would help, but didn't want to spend the $400 to find out it doesn't.

No, I've tried different combinations of brands and stations. Only the better ones, 76, Shell, Chevron, Mobil.

Since I found a temporary solution by increasing octane, I'm quite confident that this is indeed the problem. Unfortunately, this is expensive and inconvenient.

How much is too much? It seems that just about everyone here has an issue with some oil consumption. Mine is around 1 qt. every 3000 miles. I would normally say that is too much, but it seems to be "normal" for the VQ.

Finally, I should mention that I took it to the dealer after a couple thousand miles. They said the knocking was normal. *sigh* Rather disconcerting for someone who's seen what detonation can do to an engine.

97supratt

iTrader: (61)

1 quart per 3k miles is not bad at all. It all depends on how hard you drive the car. If you use the upper rpm's quite often, then you will have more oil consumption. As long as you're not around the 1 quart per 1k mile area, you're okay.

As for the detonation, the only time you will actually see a motor blow from detonation is hard detonation. Usually that happens so fast, the knock sensor can't retard timing fast enough and it blows. You can definitely hear the difference between small knock and hard detonation. Small knock is usually from timing, hard detonation is caused by dangerous A/F ratios and high cylinder pressures.

Wired 24/7

iTrader: (2)

I burned 1.5 quarts in 5k miles. Not too bad.

Finally, do you have any mods, and have you ever reset your ECU?

I live in the west LA area near UCLA if you want to swing by.

Black_Sunshine

Nope, no mods. I've been holding off mainly because of this. Not looking at anything radical, perhaps the MREV and a Popcharger, exhaust, etc. I've never reset the ECU. Does that whole gas pedal procedure work for the 06 models?

UCLA is maybe 40 miles or so, not too far. I'll think about seting something up, maybe if there's a meet or something sometime soon. Thanks again for the offer.

Black_Sunshine

Still seems somewhat high (from my experience), even for a new engine. I'm not necessarily worried about it just yet.

I'm sure it's not too serious. It's loud enough to hear though, and I find it a bit unsettling. But then, I'm old school. Or just old.

Wired 24/7

iTrader: (2)

Pedal reset won't reset the ECU fully, only check engine lights etc. You have to disconnect the negative battery terminal overnight, stomp on the brakes just to be sure everything is drained.

It might help, it might not help.

Zreign

I too have noticed pinging under load at low rpm. I use the same method that I used on my honda motors, which is to never let the rpms dive lower than 2k on flat land and 3k on hills.

My last honda motor had 12.5:1 pistons and a .001 mill on the head bringing the cr to the 12.7:1 - 12.9:1 range. With upgraded fuel system and tune i was able to run on 91 octane here in cali by simply never letting the engine drop below 2500 rpm, and also launching smoothly from a stop.

I personally drive the Z in the 2500 - 3000 range and shift at 3500-4000 during normal driving. The few dollars i lose when i gas up is nothing compared to the piece of mind i receive from driving this way. (and its a whole lot more fun)

Z1 Performance

iTrader: (564)

or you could have just turned your timing down by a couple of degrees and driven like a normal person without thinking ^

97supratt

iTrader: (61)

Detonation is dangerous at higher rpms from 5k-7k i think. I've read somewhere that it will damage the motor at higher rpm's because the stress tolerances are pushed further with the increasing engine speed.

Zreign

Hehe indeed.

However, retarded timing = less power = bad (in my case)

After years of driving touchy cars, bumping up my rpm 500 more than the normal person during normal driving was no big thing.

2 degrees could easily be 10whp

Zreign

I'm sure the risk of damage increases as the loads increase at higher rpm. Ive heard that stock Z's run rich in the top end (i know mine sure does) to avoid this problem and to increase reliability.

The good news is that this problem can be completely resolved with an upgraded fuel system and a good tune.

Give it some time and i guarantee we'll see street driven n/a VQs with 12:1-13:1 cr tuned on 91 octane pump gas. The key is to have 2 separate fuel maps: one for 91 octane and the other for race fuel.

ByThaBay

check out my update:

http://g35driver.com/forums/showthread.php?t=75477