Accord Euro 2006 - Need assistance with potential issues

[aaronng]

Sorry I'm not sure what you mean by "set cruise". Can you please clarify ? If you mean cruise control, then that's definitely not the case. So to give a simple example: from stationary, i hit the gas uniformly untill car is say mid gear 2 (say 30kmph), and then i just lift my foot off the gas (but not putting it on break). As soon as my foot leaves the gas, the rpm arrow drops below 1000rpm, and immediately bounces back to above 1000rpm (and then stays there).

When you do this on most cars, doesn't the rpm just fall to above 1000rpm and stay there ? i.e. there is never that dramatic bounce below 1000 and then back up.

Never happens on higher speed / gears, only on slow speed / low gears.

Every car has a flywheel, even an auto transmission one, and when you release your foot off the gas, the flywheel will start to slow down. It will slow down quickly until under 1000rpm when the ECU finally decides it is too low and tells the electronic throttle to give it a bit more gas to keep the RPM up. If you get someone to observe the RPM dropping, it should dip below 1000rpm but still stay above 700rpm or so. Old auto transmission fluid can also contribute to this. Because of the way the torque converter works by using the transmission fluid to create friction in the torque convertor as the RPM increases, old fluid can have more slip which contributes to it.

If the transmission fluid has not been replaced in the past 2 years or you have no records of it being done, I recommend that you do it. Use only Honda auto transmission fluid (ATF).

Thanks those are useful starters. Yes, i would say the "drumming noise" is somewhat diesel-sounding (although not as loud, but clearly distinguishable from normal). That's alot of suggestions though, can you list them in descending order of likelihood (i.e. first one being the most likely and last one being least probable) ? What will a mechanic charge for them ? Sorry i'm very new to all this.

If it sounds like a diesel, and it is worse when it is cold, then you need to get the valve clearance of the engine checked and adjusted if required. This is part of the service schedule and should be carried out every 2 years or 40,000km.

I've fueled up with 98 Octane twice during the 3 weeks i've owned the car. Although i suspect the previous owner may have used E10. Does prolonged use of E10 harm the Euro ? And if so is it reversible ? Would it help explain any of the symptoms i'm experiencing ?

E10 itself is ok, but the majority of E10 out there is 91 octane, which is way below the minimum requirement of 95 octane. As long as the previous owner did not thrash the car on 91 octane, the engine will be fine. The ECU listens for knock from using too low an octane and adjusts the air/fuel mixture accordingly to protect the engine.

Really ? So there is no ways to ease that sensation ? I live in neighborhood with lots of hills and this is very annoying. Never happens in previous cars i've driven (incluidng a Honda CRV)

It is actually a feature so that the car slows down using engine braking when you are going downhill and you will end up using less of your brakes (and making it last longer). The ECU learns your driving style and changes to suit, so if you find it annoying, just use your brakes more when you are going downhill and after a while it should remember that and use less engine braking.

So to give a simple example again. Road is normal (flat), everything is normal. Then road goes downhill, and the REV arrow slowly goes up up and up, all this time the engine feels like its stalling, steering wheel is very hard to turn, and the car just feels "heavier" (not sure how else to word it). REV just climbs higher and higher but never shifts into next gear. Its like the car is really struggling or stuck on something, hence i used the term "stuck" on a gear. Vibration and shakes are felt.

When this happens again, stick it into semi-auto mode and shift it into the next gear. Do this for a few days and see how it goes. Also, it shouldn't vibrate that badly. Change the auto transmission fluid and see how it goes.

For the same going downhill scenario, if i put the car in N, then everything is just fine as i go down the hill - no heavy sensations and no vibrations / shake.

It's because you don't have a revving engine and a revving gearbox. So at least you know where the issue is coming from. In addition, check the accessory belt. There is an auto tensioner for the belt behind the power steering pump and it has a triangle which points at a large rectangle and a smaller square on it. The triangle should point at the large rectangle or be in between the rectangle and the square. If it is pointing at the small square or even beyond that, then the belt needs to be replaced.

Is this a replaceable part and if so how much does it generally cost for a mechanic to replace it ?

Yes, it is replaceable and is actually a wear and tear item that should be replaced after a few years. I buy mine from the parts shop for about $60 and replace it myself. The belt width and length is 7PK1760 (7 ribs, 1760mm circumference). If you can't find this one, then 7PK1750 is fine as well.

[darknoodles]

If the transmission fluid has not been replaced in the past 2 years or you have no records of it being done, I recommend that you do it. Use only Honda auto transmission fluid (ATF).

Do i need to empty the current existing ATF a few times (think i read this somewhere), or just empty once and fill up with Honda ATF ?

If it sounds like a diesel, and it is worse when it is cold, then you need to get the valve clearance of the engine checked and adjusted if required. This is part of the service schedule and should be carried out every 2 years or 40,000km.

It is actually not too bad on cold, worse when warm.

It is actually a feature so that the car slows down using engine braking when you are going downhill and you will end up using less of your brakes (and making it last longer). The ECU learns your driving style and changes to suit, so if you find it annoying, just use your brakes more when you are going downhill and after a while it should remember that and use less engine braking.

I had no idea the ECU actually learns the driver's habits overtime. If so i'd like to reset it as recommended - it makes sense because driver has changed. Would resetting the ECU bring any unwanted results ?

Yes, it is replaceable and is actually a wear and tear item that should be replaced after a few years. I buy mine from the parts shop for about $60 and replace it myself. The belt width and length is 7PK1760 (7 ribs, 1760mm circumference). If you can't find this one, then 7PK1750 is fine as well.

Thanks.


I have been to Hanny's @ Smithfield about 2 weeks ago (recommended by a friend), but Robert took it for a drive and said no major issues found, and sent me off without any servicing. Basically he stepped on the gas alot and so didn't really get to feel much of the issues. If i do return there, what should i say and request for ? I don't want to be explaining the whole story of what im feeling here and there, because they are just going to brush it off as a non-issue again.

[aaronng]

Do i need to empty the current existing ATF a few times (think i read this somewhere), or just empty once and fill up with Honda ATF ?

Doing that would be very expensive for you. I'd just empty once and refill. Then do it again in 1 year's time.

It is actually not too bad on cold, worse when warm.

The only things worse when warm would be carbon deposit buildup in the combustion chamber (you can use Wurth's upper cylinder head cleaner), possible if the previous owner was running on 91 octane and the engine was running rich to prevent knocking and thus putting a layer of carbon deposits in the combustion chamber.

I had no idea the ECU actually learns the driver's habits overtime. If so i'd like to reset it as recommended - it makes sense because driver has changed. Would resetting the ECU bring any unwanted results ?

Resetting the ECU should reset the short and long term fuel maps. I'm not sure about the gearbox driving history, but worth giving a try anyway. You just get the engine running slightly rich for an hour or two.

I have been to Hanny's @ Smithfield about 2 weeks ago (recommended by a friend), but Robert took it for a drive and said no major issues found, and sent me off without any servicing. Basically he stepped on the gas alot and so didn't really get to feel much of the issues. If i do return there, what should i say and request for ? I don't want to be explaining the whole story of what im feeling here and there, because they are just going to brush it off as a non-issue again.

Just ask him to do a change of the auto transmission fluid. It might cost you over $100 though, but it is one of the fluids that should be changed after buying a car that is pre-owned with reasonable kms on the clock.

[darknoodles]

Okay thanks aaronng, i'll get a service done in the very near future and report back.

In the meantime any other suggestions are most welcome.

[darknoodles]

Hi all,

Car was serviced by a mechanic a few days ago. Specificaly the following was done.

Changed engine oil
Change Auto Trans Fluid
Changed Air filter
Clean throttle body
Other things that would fall under "general service"
ECU reset

Total cost of $120 (parts) + $250 (labor) = $370

The pulley belt was not changed, because the mechanic deemed it "OK" and didn't see the point of changing it, and so i didn't pursue any further. Should i have ?

Overall there seems to be a slight improvement, but the fundamental issues are still there

The biggest improvement has been the downhills "stuck gear" sensation. I can now clearly feel the difference (the so called engine brake) compared to before - which was really jerky and ...well weird. So its good on that front.

It still very much concerns me that nothing much has changed otherwise. The biggest concern has always been the drumming noise (point 2 on front page)....Without sounding repetitive, basically this issue typically occurs when,

-> i am travelling on 2/3/4th gear
-> then i just let go of the gas and don't touch the brakes (e.g. coasting towards a far red light)
-> as soon as i let go of the gas, the drumming noise starts -> all this time while i am coasting (no gas, no brake) the drumming noise continues, untill eventually when i step on some brake
-> the drumming noise slowly phases away, but just before the noise completely disappears, the car feels very heavy like it has alot of forward thrust, and the sterring wheel is hard to turn (feels heavy)
-> then there is a definitely mini forward jerk, and then the durmming noise completely goes
-> car brakes back to normal.

The above occurs far more often when the car is warm. Almost never happens on say the first 3 mins when cold started.


I would really appreciate any input anyone might have on this annoying problem. aaronng did suggest cleaning possible carbon deposit buildup in the combustion chamber...i do not know if that was performed by the mechanic. Can i please get some further insights to this problem ?


Thanks.

[aaronng]

Hi all,

Car was serviced by a mechanic a few days ago. Specificaly the following was done.

Changed engine oil
Change Auto Trans Fluid
Changed Air filter
Clean throttle body
Other things that would fall under "general service"
ECU reset

Total cost of $120 (parts) + $250 (labor) = $370

The parts cost is too cheap. What air filter and fluids did the mechanic use? Doesn't sound like the it was an original air filter or Honda ATF.

The pulley belt was not changed, because the mechanic deemed it "OK" and didn't see the point of changing it, and so i didn't pursue any further. Should i have ?

Check it yourself by looking at the belt tensioner with a flashlight.

-> i am travelling on 2/3/4th gear
-> then i just let go of the gas and don't touch the brakes (e.g. coasting towards a far red light)
-> as soon as i let go of the gas, the drumming noise starts -> all this time while i am coasting (no gas, no brake) the drumming noise continues, untill eventually when i step on some brake
-> the drumming noise slowly phases away, but just before the noise completely disappears, the car feels very heavy like it has alot of forward thrust, and the sterring wheel is hard to turn (feels heavy)
-> then there is a definitely mini forward jerk, and then the durmming noise completely goes
-> car brakes back to normal.

The above occurs far more often when the car is warm. Almost never happens on say the first 3 mins when cold started.

If it was a transmission problem, then the steering wheel shouldn't become heavy. If the steering wheel becomes heavy, it could be an issue caused by either the power steering pump or a slipping pulley belt. Check the pulley belt tensioner position first. Does the triangle point to the small square or the larger rectangle?

[darknoodles]

If it was a transmission problem, then the steering wheel shouldn't become heavy. If the steering wheel becomes heavy, it could be an issue caused by either the power steering pump or a slipping pulley belt. Check the pulley belt tensioner position first. Does the triangle point to the small square or the larger rectangle?

i took a 10 min look around the pulley but couldn't locate the triangle (or square or rectangle) you mentioned. Apologies im not much of a DIY person when it comes to cars.

below are 2 photos, can you possibly indicate where these are (maybe just draw an arrow or something) ? Or do i need to remove something first ?

if i didn't even get close, would there be any photos on the net showing how i could locate it ?

Thanks.

[jono_l]

The auto-tensioner pulley is the small black pulley (smallest ones in the picture). The square/rectangle sits directly next to where "PNA" is stamped on the auto-tensioner unit, and the little triangle is right next to that. Good luck with it mate!

[aaronng]

^^ what jono_l said.

Have a look at the marks when the engine is off and when the engine is at idle. Also, check if the arrow is moving wildly around when at idle.

If the mark is pointing to the small square when off - Belt is worn
If the mark is pointing to the middle when off but to the small square when engine is idling - Belt is worn
If the mark is moving around and doesn't stay at one spot when idling - auto tensioner is worn
If you hear a crunchy sound from the small black pulley on the auto tensioner - bearing in tensioner pulley is worn

Here is another picture which clearly shows the small square and large rectangle. Note the triangle is pointing way beyond the small square in this photo, showing the belt is either extremely stretched or is of the wrong length.

[darknoodles]

Thanks both. This is the position of my triangle.

It points to this position when off and also when engine is idle (i.e. idle or off doesn't seem to make a difference, and i kept it on idle for around 5mins). When idle the triangle doesn't move around - its fairly steady.

Whare are next steps ?

[aaronng]

Thanks both. This is the position of my triangle.

It points to this position when off and also when engine is idle (i.e. idle or off doesn't seem to make a difference, and i kept it on idle for around 5mins). When idle the triangle doesn't move around - its fairly steady.

Whare are next steps ?

[IMG]http://i52.tinypic.com/2i6melx.jpg[IMG]

So you've ruled out the accessory belt and the tensioner. If the steering gets heavy under deceleration, what RPM does that happen? What RPM is the engine at when the vibrations start to occur? Does it also happen when you are accelerating at that same RPM point?

[darknoodles]

So you've ruled out the accessory belt and the tensioner. If the steering gets heavy under deceleration, what RPM does that happen? What RPM is the engine at when the vibrations start to occur? Does it also happen when you are accelerating at that same RPM point?

Yep sure. The vibration / drumming noise occur around the 1200-1300 RPM. Here's a typical sequence,


-> from stationary, step on gas uniformly and reach say 3rd or 4th gear
-> take feet off gas and just coast forward (i.e. no gas, no brake either)
-> after feet off gas, rpm drops quickly to around 1200-1300rpm, and drumming noise occurs. Car feels like it has some forward thrust and a little shaky.
-> while drumming noise is still there and needle still around 1200-1300rpm, I step on gas again. Drumming noise disaapears and RPM goes up uniformly as normal, and car is not shaky.
-> take feet off gas again and just coast forward (i.e. again no brake)
-> RPM drop to 1200-1300rpm, drumming noise returns (sometimes even louder than before) and pretty much same symptoms

brake is never used in the above scenario

Of course as with most problems, it does not always occur 100% of the time. As i mentioned it usually is ok when car is cold, and occurs often when warm. Drumming noise is more pronounced when the car has been driving around for long time.

[ not sure if this will help ] .. I should also add that, if i take my feet off the gas just before going into the next gear, the noise is more pronounced, i.e....

-> step on gas uniformly and reach say 3rd gear. While on 3rd gear, still apply gas as normal, but as it is about to shift to 4th gear, take feet off gas and just coast (no brakes)
-> drumming noise occurs like mentioned above. Done this way, the noise is sometimes louder, and overall the noise just appears more often. RPM is still around 1200-1300 when noise occurs.