Luchin

I'm posting this here because the 'Is there an ignition timing issue' is six pages long and I wanted to bring attention to this now.

We have two 09 TSXs and both are 6MT. I only use Chevron gas in both our cars. When I use 92 Octane we have a 'knocking' problem, using 94 octane seems to fix the noise.

Has anyone else experienced this. Not the knocking but the absence of when using higher octane gas?

TSXding

I only use 93 and have the issue. Not even sure where to get anything higher than 93 in the North East.

ttk5

is this knocking sound noticeable? i have a 6spd tsx and if I had this problem I probably would have noticed it by now right?

Luchin

maybe and maybe not. It generally happens, for me anyway, between 3500 and 4500 rpm under heavy load. That means accelerating with your foot to the floor. Good luck.

thefish

I noticed a wierd whine when I filled up with 91 octane from a 76 station. My last 2 fill ups were at Chevron and Shell and I haven't noticed it. 91 is the highest octane out here in CA and it's all I use.. maybe it's the supplier?

Oh and in the northeast I believe Sunoco carries 94.

DerwoodEE

I've been using 95 since day one and have never experienced this issue.

I live in race country, so 95 is pretty readily available.

Luchin

The whine is the oil pump. My wifes car sounded like it had a supercharger under the hood for seven months while Acura tried to figure it out. In any case they finally fixed the problem. They all make that sound but her car was stupid loud.

09TSXTech

I use Mohawk/Husky Oil Premium 94 w/10% ethanol in Vancouver, no knock at all in the past 9 months even in WOT. Mine is a 6MT Tech.

HeavyDuty

I run 93 in the TSX, that's the regular high grade here. We also have Sunoco 100 unleaded, but that's for the white car.

Mine is a 6MT and I've never heard any pinging, even high load low speed in August in Florida with 4 people & the a/c on.

ctwickman

I heard this knocking for the very first time yesterday. Funny it should happen on the one tank of gas that was not Shell 93. I used Andy's 93 which I'm not sure is Top Tier gasoline. Needless to say I will be switching back to Shell.

Mwing

chevron 92 knocking, will try 94 next time

kristy7911

Can someone please explain to me what knocking sounds like?

patcracks

it sounds like a baby rattle when your stepping on the gas

kristy7911

wow. definately not something i have heard yet. thanks!

Luchin

You almost need to be listening for it to hear it. I wouldn't say it sounds like a baby rattle. I would say it sounds more like addings BB's to a can that is already half full of BB's. It's that sort of soft metalic sound.

If you can't hear it don't look for it because once you hear it, you always hear it.

My only concern with the fact that it isn't there with higher octane gas is that it is knocking which DOES damage the engine. If Honda knows about it they are smart to say it isn't knocking. Can you imagine the cost of recalls and warranty issues if people knew their engine was knocking for 12000 miles. Ouch.

HeavyDuty

You realy ought to read the 6 page thread, Lou. There was a communication from Honda corporate about this noise being a "post-combustion event" that was occuring in the exhaust downstream of the cylinder head port.

As mentioned on the other thread:
https://acurazine.com/forums/2g-tsx-problems-fixes-145/003-there-ignition-timing-issue-%2Aupdate-tsb-pg-12%2A-684180/

if the knock sensor "hears" or rather "feels" pinging, it would retard the timing until the event didn't occur. I really need to get an auto TSX loaner next time @ Acura to see if I can make this noise.

TSXding

Didn't the "post combustion" theory or announcement come out of Australia regarding 2008 Euro? I do not think Honda has made any announcement or any direct correspondence regarding the TSX noise. I could be wrong, but I've seen no confirmation of corporate saying anything yet.

HeavyDuty

Yeah, IIRC, they've been having it longer than we have. The OZ members here have contributed a lot to the discussion.

My point was that if it is pinging in the cylinder, the knock sensor should compensate. The post-combustion noise sounds the same to those experiencing it here as well as there, I would think.

ttk5

haha great advice!!

Luchin

Ahhh well, I don't mind reminiscing of the days when I used to drive the old farm tractor every time I accelerate. Hahaha.

Luchin

I did read it. Remember I made reference to six pages being the reason I started this thread. Now it looks like it's going the same way as the other thread. This was mainly to see what experience anyone else had using 94 instead of 92 octane. Not wether or not the engine was knocking.

HeavyDuty

I hear you, and in that thread it did mention that others changed octane with no results and there may be others still who changed and did yield a difference, but personally I would still keep it there to keep it all together.

It's all good, I'm not a moderator or trying to be, nor am I trying to tell you what to do, it just seems to be more clear to keep it all together.

Luchin

I genereally don't take offense to anything anyone says. It's all good. No hard feelings about anything at this end.

phonic

From what I remember reading, if you put lower octane gas in the TSX it isn't supposed to knock but re-time the engine so that the hp drops. I'm using 94 here.

Altitude is also supposed to determine the internal combustion and change the way a certain octane will perform. I think it is that if you're in a higher altitude you need a higher octane to achieve the same performance you would get in a lower altitude. Please correct me if I'm wrong or if I got the altitude thing backwards.

Mwing

i got the result

i put 55L of chevron 94 octane on friday, up until now there is no pinging noise, and the engine sounds more crisp or clean.

i will try going back to 92 octane to see if the noise comes back.

melody

LOL, no kidding.

I heard it for the first time this week in my 5AT. I use 91.

Luchin

I was mistaken. The noise is present even if I use 94 Octane. However, it is intermittent. Sometimes the noise is there, other times it isn't.....So maybe the first time I ran the 94 the car was having a good day.