Some pinging

[Garu]

I've been noticing very mild pinging when the rpm is decreasing from about 2500 to 1000. I usually notice it at 1500 to 1100. The exhaust produces sort of like double pop. Pinging is the right terminology here right?

I've been using Esso since I've got the car, I decided to use Sunoco 94 octane. See if it's gas related. I'm just first 1/4 of the tank so I'll see if there is any change. But oh boy, Sunoco's gas does burn lot faster.

[Wild Weasel]

Haven't heard any such thing from mine, but I'll start paying closer attention.

[matt]

i think it burns faster b/c of higher ethanol content, same thing with the crappy tire gas. from what i read, ethanol increases octane but it burns faster

[Unoriginalusername]

higher octane gas is actually more difficult to burn... more like you're foot is heavier with the good stuff lol

[Garu]

Welp after half tank of Sunoco 94, the problem disappeared. I'm guessing ESSO's crapimium caused it.
I'll try Shell next time.

[Unoriginalusername]

Welp after half tank of Sunoco 94, the problem disappeared. I'm guessing ESSO's crapimium caused it.
I'll try Shell next time.

esso followed by petro are the worst imo... no fact, just opinion based on experience with their product vs. others

[TurboEight]

is that right..how many here run shell's v power? with boost.

[Flagrum_3]

I've been noticing very mild pinging when the rpm is decreasing from about 2500 to 1000. I usually notice it at 1500 to 1100. The exhaust produces sort of like double pop. Pinging is the right terminology here right?

That popping you hear is called back-firing, and you will probably notice it with any fuel you use (some more than others), its quite normal....its just unburned fuel/air mixture which makes its way to the exhaust.Pinging on the other hand is actually pre-detonation occuring in the combustion chambers and occurs when the vehicle is accelerating or under load. (It sounds like marbles rolling around in the engine)


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[Wild Weasel]

I don't think modern cars backfire. If you've got that much fuel ending up in the exhaust, then you're going to kill your cat and probably have serious emissions issues.

[Flagrum_3]

I don't think modern cars backfire. If you've got that much fuel ending up in the exhaust, then you're going to kill your cat and probably have serious emissions issues.

Of course they do, you just can't hear them because of the excellent emissions systems today! and That is exactly one of the things the Cat is designed for, to catch unburnt fuel.Get an aftermarket cat-back they'll (the pops will suddenly appear much more noticeable).


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[Unoriginalusername]

srt4's pop lots for example

[alhope34]

is that right..how many here run shell's v power? with boost.

That's the only gas I've put in the 'speed3 since I bought it, and that was 2800kms ago. No pinging or odd sounds at all. My car purrs really nice.

[Unoriginalusername]

That's the only gas I've put in the 'speed3 since I bought it, and that was 2800kms ago. No pinging or odd sounds at all. My car purrs really nice.

is there a prize at 50 posts... why all the old post re-hash's?

[alhope34]

is there a prize at 50 posts... why all the old post re-hash's?

Yea, I thought I could post a WTB finally in the classifieds. But apparently I still can't.

[Unoriginalusername]

Yea, I thought I could post a WTB finally in the classifieds. But apparently I still can't.

lol figured... maybe a mod can unlock it, or someone can post for you

[alhope34]

maybe a mod can unlock it


That would be really nice....hint hint...if any mods see this.

[Unoriginalusername]

That would be really nice....hint hint...if any mods see this.

just pm one as they might not see every post

[Skarbro]

I don't think modern cars backfire. If you've got that much fuel ending up in the exhaust, then you're going to kill your cat and probably have serious emissions issues.


Of course they do, you just can't hear them because of the excellent emissions systems today! and That is exactly one of the things the Cat is designed for, to catch unburnt fuel.Get an aftermarket cat-back they'll (the pops will suddenly appear much more noticeable).


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From Wiki:


In older engines, backfiring may be considered normal. Backfire is rare in modern cars with fuel-injection and computer-controlled fuel mixtures.
Common causes of back fires in the intake manifold are bad spark timing, or incorrect (usually lean) fuel ratio.

[garboui]

backfiring is evem more impossible with your guys engine because of the direct ingection

[royroy]

V-power for me too =)

[RX9]

V-power, "contains no ethanol" said on pump. thats nice.

[Flagrum_3]

From Wiki:

If you didn't notice it seems they are talking about intake manifold backfires, which thier right, and do not happen anymore as in the old carburated days.But we are talking exhaust here and most definitely even with our computers, better plugs, direct ignition etc, etc; ...there is still a percentage of unburned fuel that gets to the catalytic converter which is why its there.Remember the Internal combustion engine is not 100% efficient, actually quite far from it.


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[Flagrum_3]

V-power, "contains no ethanol" said on pump. thats nice.

I could be mistaken but I believe Shell has changed this recently, but the percentage of ethanol is still lower than in the lesser grades.


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