Engine Pinging (

[JDMMA70]

Im actually posting this for a friend, he called me this morning when he arrived at the university that his engine was pinging/knocking and was inttermittent in sound sometimes it would be quiet so quiet you couldnt tell it was there and then sometimes it would be loud. I told him hed have to wait till i looked at the car. It hit me in the afternoon that he had been running 87 octane, in his 90 Turbo. I asked him if he had been boosting lately and he replied "yes" that he had. He decided to drive the car back to see if he could make it home. On the way he stopped at a Chevron and pumped $5 of 93 and the pinging sound got quiet again but a block from his house it got loud again. So my question is did he spin a bearing (we just replaced the HG on his car, drained the oil and coolant, changed the oil 3 times, once after the first 20min, again after he drove around the block, and again before he started driving the car again), or is it because hes running 87 octane. He didnt set off the knock sensors.


Help would be great thanks
~JDMMA70

 

[92TealSupra]

We can't tell you what he did. Rod knock sadly does not " go away " if it does disappear for certain periods of time it is not a spun bearing. The 7m-gte does like to have 93 octane though, and he is using 87.

 

[hvyman]

did u change spark plugs? and run 91

 

[JDMMA70]

did u change spark plugs? and run 91

no hes gonna drain the tank tommorow and install new plugs

 

[92TealSupra]

If he is trying to figure out what is wrong, start with the correct fuel.

Then if it does not go away use a stethoscope, and see where this pinging is coming from.

 

[JDMMA70]

If he is trying to figure out what is wrong, start with the correct fuel.

Then if it does not go away use a stethoscope, and see where this pinging is coming from.

thats the plan, i had told him, i was looking for someone elses advice who perhaps has more knowledge on this than me. So thank you 92TealSupra and Hvyman.

 

[92TealSupra]

No problem. I am sure it's going to work out, and it surprises me that he uses such a low octane, when he knows he shouldn't, maybe he will learn though.

-Eathen

 

[jdub]

There's no way you can tell if you "set off the knock sensors"

I highly doubt this is a gas/octane issue...a knocking/pinging sound due to detonation is not going happen due to fuel a low RPM cruise.

 

[92TealSupra]

There's no way you can tell if you "set off the knock sensors"

I highly doubt this is a gas/octane issue...a knocking/pinging sound due to detonation is not going happen due to fuel a low RPM cruise.

He said it went away for a little while, would you think this is could be a noise in the head?

 

[jdub]

Could be a variety things...valve noise, crank damper bolt loose, rod knock, acessory pulleys, etc.
Gas octane is not it though

 

[92TealSupra]

Could be a variety things...valve noise, crank damper bolt loose, rod knock, acessory pulleys, etc.

The noise went away though, and continues to do so. Rod knock would be a constant noise occurrence.

 

[Sside]

No problem. I am sure it's going to work out, and it surprises me that he uses such a low octane, when he knows he shouldn't, maybe he will learn though.

-Eathen

It was me, I did it ... I pumped low octane... I dont pump low octane but since the hurricane, gas stations dont have 93... I was in a hurry to school so I couldnt drive 25 min to were there was 93 octane... I knew it was bad but never imagined it be this bad... I said I am going to pump my gas and hopefully soon tomorro Chevron has my supreme but this happened... : ( Thanks for the help so far guys...

 

[92TealSupra]

It was me, I did it ... I pumped low octane... I dont pump low octane but since the hurricane, gas stations dont have 93... I was in a hurry to school so I couldnt drive 25 min to were there was 93 octane... I knew it was bad but never imagined it be this bad... I said I am going to pump my gas and hopefully soon tomorro Chevron has my supreme but this happened... : ( Thanks for the help so far guys...

Well don't worry, just make sure you pump premium back in there, I was pretty sure there was a reason why you did this, and yours is indeed legit. Hope you get that Supra running back to where it should be, good luck.

 

[jdub]

Jeez guys...the manual allows the use of 87 octane. Used it several times myself. It will not cause ping unless you're running at high boost...on a stock CT26, that's above 5000 RPM at least.

Teal - I'm not saying it's rod knock, though that's a possibility even though it seems to come & go.

 

[IJ.]

Wonder if he has an EGR

 

[92TealSupra]

Wonder if he has an EGR

Good question.

 

[grimreaper]

Lmao

 

[snake eyes]

It was me, I did it ... I pumped low octane... I dont pump low octane but since the hurricane, gas stations dont have 93... I was in a hurry to school so I couldnt drive 25 min to were there was 93 octane... I knew it was bad but never imagined it be this bad... I said I am going to pump my gas and hopefully soon tomorro Chevron has my supreme but this happened... : ( Thanks for the help so far guys...

which university you go to? Im at UH main.

Another for getting a listening device and finding where its coming from, that should help get an idea where its coming from.

<l><l>

 

[jdub]

Wonder if he has an EGR

:runaway:

Good question.

Trust me, I though about it. Seems if I point out anything about the EGR, I'm flaming people

 

[gaboonviper85]

just wondering...when you hear the noise, are you under 2000rpm and a higher gear "let's say 3rd" and trying to drive slow and easy to save gas? Sounds to me like your just lugging your engine and your hearing chatter.