I've had a 2005 TL - 6speed, 2006 TL auto and now a 2007 TL - Type S auto and all three have made this particular pinging noise off and on. In AZ the gas stations carry 91 octane and I always use it. I brought it up to the dealer on the 05 & 06 but was told it could not be reproduced and the computer showed no trouble codes. I haven't addressed it yet with my 07 but figure will get the same message. But at least it will have record on file that I brought it up.

 

Pinging, valve rattling, or what ever you want to call it is the result of pre-detonation. Pre-detonation occurs when the air-fuel mixture in the cylinder ignites pre-maturely, and is due to over-advanced ignition timing, too low an octane fuel for a given compression ratio, lean fuel mixture, overly high combustion chamber temperatures, non functional-wrong EGR valve, or glowing carbon deposits within the cylinder head combustion chambers.

Since my TL-S only has 3200 miles on it, my guess would be that the ignition timing curve is slightly too aggressive, and advancing too much for the given throttle opening and rpm. The downside to toning down the timing curve would be less performance and less fuel economy. A more aggressive EGR rate would probably cure the problem, but the outcome may be surging or decreased part throttle performance.

I don't know what the answer is for this particular situation, but I do know that constant "pinging" is not a good thing. I have seen first hand that it can break the ceramic insulators around the spark plug electrodes, and the resulting pieces will end up on top of the pistons. From expensive first hand experience I do know that cylinders, pistons, valves, rod bearings, rods, and crankshafts can all suffer from continued and regular pre-detonation.

Let us hope that Acura has engineered for this "pinging" and has carefully designed the engine to handle it, because what sounds like a minor valve "rattle" is actually a very forceful internal explosion that occurs before the valves are closed during the compression stroke.

Lee

 

Started a Poll on this Issue. I put it on the main board for maximum exposure. So if you would like to vote its there. At least we will get a concensus and maybe see if this is a problem for all Type S owners.

 

Finally, someone who knows about cars. Even minor detonation or preignition for periods of time is bad. Think about the sound you're hearing. It's the mixture being ignited while the piston is still traveling upward trying to force it back down the wrong way. Combustion pressures rise 10+ times the normal WOT pressures. Everytime you hear this noise, you're doing some sort of damage. Over time it hammers ringlands in pistons, rod bearings, and eventually headgaskets. If severe enough it breaks hard parts. I owned my turbo car from the time I was 17, before there was a lot of info on tuning and I learned the hard way with detonation with a minimum of 6 blown headgaskets, one broken ring land (on a forged TRW piston), one cracked cylinder and I've hammered the bearings on two motors. Now I'm a little older and smarter and tune with a laptop.

Also, if you can hear the noise with your ears, it's pretty bad. On my turbo car the knock sensor picks it up way before I can hear it. Acura is going to have lots of warranty claims if they don't do something about this. Like was said, a little less aggressive timing curve or more EGR will usually cure this.

 

Yep..cuz it defective and your engine will not last you very long....I Hate Cars has a great explantion and a quoted explantion from cbronze07.....both members accurately explain the effects of this pinging....

 

In my previous post, I stated that "what sounds like a minor valve "rattle" is actually a very forceful internal explosion that occurs before the valves are closed during the compression stroke".

This statement is not really accurate, and should read " what sounds like a minor valve "rattle" is actually a very forceful pre-mature internal explosion that occurs before the ignition system fires the spark plug during the compression stroke"

Sorry for any confusion,
Lee

 

If this is a pre-detonation issue due to timing issues, I wouldn't expect the valves to be open during compression? How else is it to compress if the valves are open? If the ignition is occurring that early, that seems quite odd, no? If it's just a matter of the fuel detonating that early without the aid of the ignition, that's different.

 

Handruin,
I attempted to clarify my incorrect statement with my previous post.

If the valves were open during the compression stroke, then there would be no compression, and therefore a non-running engine.

Pinging, valve rattling, pre-detonation, and pre-ignition are all just different names for the same thing.

 

Preignition is when the mix lights off too soon whether from ignition timing too advanced or heat/compression/boost/etc. Detonation is when you have two flame fronts that collide in the combustion chamber from hot spots, compression, boost, etc. Usually detonation is preignition too if that makes any sense.

If you've ever seen engine parts from prolonged preigntion/detonation you'll know what I'm talking about. I've seen pistons that looked like you took a small chisel and hit it a few thousand times in the same spot until it was down to the first compression ring. I've had my methanol nozzle plug up at 28psi boost on my Buick and by the time I could react to let off the gas my headgasket was literally sticking out between the head and block. That's the kind of thing detonation will do. You're lucky if the headgasket is the weak link. I'm actually proud of that one.

 

New WORD same meaning, Google "Spark Knock", thats what I learned many years ago.

 

Close, but detonation and preignition are two different things.

 

Well, I tested my TL-S engine again, and I can still hear the rattling when I accelerate heavily from a low to high rpm - usually after I have been driving mellow for a while. I just took the car into the shop for a defective starter, and if this is indeed an "as designed" issue that they cant/wont fix, I don't think I will take it in at all. Hopefully a slight rattle will be ok for the engine.

 

Any updates Guys? Bionic, MD, Cbrone, any updates on your pinging situation?

Did anyone try the TSB Will Y. posted in this thread?

 

I am still hammering Acura Corporate. Nothing will ever be done until EVERYONE calls them. Specifically, call the case manager who I am dealing with.

Acura
800-382-2238
Leon Jones, case manager, eXt: 115004

 

I did look at the heat shields under my car, and cant find any that are loose or would rattle, but the noise I am hearing is definitely the valves rattling.

I will definitely call Leon about the problem, because I want my case started if there is a future engine problem due to the pre-ignition.

 

Yes, that sounds like a good idea.

Bionic, It would proably be a good idea for Leon to communicate with the Acura Tech service line rep that your dealer spoke with so that they can move beyond the denial game. You might also want to email him a link to this thread and the ping poll thread. Just a thought.

 

Any news on this issue?

 

Does the RL engine have these issues .. or is the 3.5 in the TL-S a completely different engine from the RL and MDX?

 

HERE WE GO....


http://www.in.honda.com/Rjanisis/pubs/SB/B07-026.PDF

 

looks like it's not true pinging or true engine issues based on that *.pdf file. Good news for you guys

 

Most Righteous find RedHot ! I hope this is it! Thanks!

 

Come to think of it, the few times I've heard it was shortly after starting the car. It happens at an inclined entrance ramp to RT 9 that is about 1/4 mile away from my friends place. When I leave, my TL doesn't get much time to warm up, and that could likely be the case.

Now that it's warmer, I still haven't heard the noise again. Those times I heard it were during the jan-feb months.

 

The TSB doesn't cover 2007 TL's of any kind. Also my "pinging" happens not during "light acceleration" but rather more spirited, but not full throttle when the RPM's get to around 4,000.

Hopefully this TSB will help some of us, but unfortunately not all of us.

 

I agree with you. The noise I get is fuel related. It is worse when the car is hot. during a 7 hour trip recently, I was getting the pinging by simply applying a little gas at cruising speed (75mph) on a flat interstate road. I goes back to what I have already therorized which is that the car has a fuel management issue. It can't deall with excess fuel at the mid rpm / transitional rpm range.

The acura factory rep is riding with me soon to experience the problem for himself.

I will let everyone know the outcome of that ride!!

 

Chevron techron anyone???

 

Bionic, any update on your pinging situation?

 

I noticed some rattle today and the day before, so perhaps it is related to the weather getting warmer? I don't know if Honda has a fix for this or not, but I wish it could be fixed somehow because it just sounds really wrong.

 

It could be fuel octane related but not excess fuel. If you had enough extra fuel to cause it to ping (very hard to do) it would be dumping a ton of black smoke. Pinging when fuel related is caused by running lean.

Anyone verify the EGR is working correctly?

Run 100 unleaded and see if it goes away? If it is still there, most likely not true pinging.

You could put it on a dyno with a wideband to see what your A/F ratio is and also stand next to it while under load and see if the noise is truly coming from the motor. This should not be this hard to diagnose.

 

I have a TL-S manual speed with just 9000 km(5500 miles) and have the same rattle noise, pinging like, in the 3000-4000 rpm range. It happens more frequently when I accelerate at partial throttle up an incline road, but it can also happens on a flat road. It is usually heard when I am in third or fourth gear, but I also heard it in second gear.

I always put 91 octane gas and I have tried them all. I do not think it is a winter gas issue since it still happens now. I once tried 94 octane gas but it did nothing about the rattle.

The TL have a knock sensor so if it is detonation and if we can hear it, it is big time detonation, the sensor should retard timing so that detonation should stop. The problem is that I can reproduce de rattle noise again and again, like if the sensor is doing nothing...

I went to my dealer but at the time(a month ago), I did not know how to reproduce the sound. I thought that it was during hard acceleration so when I went for a ride with the tech, we heard nothing. This week I'll take and appointment for another road test with the tech.

 

Honda has pretty noisey valves when the engine is cold.. After a bit of driving the chatter goes away. Have you asked the service dept. to check the valves and make sure they are all within the factory recommended spec?

 

The noise occurs even when I drove for 100 miles. I always make sure that the engine is well warmed up when I tried to reproduce the rattle. Now, I just need a nice paved inclined road to make the rattle. Anyway, I just want that my record for the car includes that I suspected some pre-ignition or detonation, and that I told my tech at the dealer about it. I bought an extended warranty so if the engine blow up, it won't cost me a dime...

 

Have you tried dropping a gear when this occurs? I know I don't have a TL; but in my accord (5 speed manual) if i'm going uphill and in too low of a gear (like 5th) the engine is bogging down and causes some abnormal noises; dropping to 4th and raising the rpm resolves it

I'm just throwing that out there - i'm guessing the TL tranny is smart enough to drop a gear when it feels that it needs it, but have you tried dropping to 4th to see if the issue goes away?

Does it ONLY happen on an incline? It could just be the load on the engine.. If you're bored and plan on going uphill sometime soon drop it to 4th or give it enough gas so it drops to 4th on its own - see if the noise persists..

 

I can reproduce it in second, third and fourth gear. It is a manual 6 speeds. The incline road I use to test is just after a stop. So when I just get through the gears(1-2-3-4) to get up to speed, the road is long and inclined enough to load the engine for the noise to occurs. Like I said, I am in the 3000-4000 rpm range so it is not that I am in 5th gear when I am suppose to be it second... It is not possible to hear the noise in 5th gear because the speed is too high and cause too much wind noise.

It happens also on a flat road. I just need to be in acceleration and load the engine enough. By the way, I do not need to be in full throttle, just partial throttle.

 

Question for everyone else then I guess.. Those of you who are getting the same chatter, do you all have manual transmissions?


Like I said - my car does it when i'm going too slow for the gear i'm in and the engine cannot produce enough power to keep the car going so it starts to bog down; when you're driving and this occurs how fast are you going? Are you in 3rd or 4th at that speed? What happens if you drop a gear? I mentioned full throttle because I wasn't sure if you had an AT or an MT.

I guess my point is.. I can reproduce valve chatter in all 5 of my gears; but it only occurs when I should be in a different gear because of my speed, engine speed, and engine load. I'm not trying to say anything about your driving skills - i'm just curious as to what's causing this problem. You've got 6 speeds and a v6, I have 5 speeds and a 4cyl; so naturally our shift points are going to be pretty different.

When you produce the noise again try bringing the engine to say... 4500 rpm (without exceeding the speed limit of course...!) and see what happens.

 

aaaand....

On the TL-S what's the "normal" engine speed for vtec to activate?

In your owners manual can you find the section that mentions the transmission? It should have a list of all gears and tell you the speed range you should be when changing to that gear - i'd like to see what the ranges are

 

The VTEC seem to activate around 4500-4800 rpm and at that range, the sound of the engine is too loud to hear the rattle. To give you an idea of the rpm to speed relationship, when I am in 5th gear at 72 mph(120 km/h) the engine is around 3000 rpm. At that speed, the wind noise makes it impossible to hear the rattle.

By the way, I do not think it is valve chatter... I am more afraid of pinging caused by detonation or pre-ignition.

 

I have a 2007 TL-S with 2000 miles on it. I am located in Co Cal, and have no pinging issues, even with 89 octane (filled up in error). Ran the car to 1/2 tank with 89, and then filled up with 91, but did not notice any pinging. Also I live in a hilly area.

Hope you guys get it sorted out.

Viraf

 

Bingo. It's not valves making the noise... This was someone's guess.

 

Bingo. It's not valves making the noise... This was someone's guess.

 

Ok, maybe I can contribute something useful. I would still like to see someone with the problem try some 100 unleaded as this will put to rest detonation problems once and for all.

I just remembered that when my car was new it did something very similar to what has been described in this thread. It had a noise coming from the center console/firewall area that could be mistaken for detonation. I immediately identified it as an exhaust leak. It mostly but not always happened when it was cold. It always happened under heavy throttle. I went through a tank of 100 unleaded that made no difference just because it was cheaper than doing headgaskets later. After about 10,000 miles it fixed itself which is common with exhaust leaks at joints. The carbon can actually fix the leak. This does not apply to cracks and such that usually get worse with time and heat. I'm getting the transmission serviced next week and I'm going to get under the car and look for any signs of a past exhaust leak.