SanDiegoDriver

I haven't seen any comments on this topic, so I'm opening up a new thread.

What is the "right" way to break in my new TSX? I've been keeping the speed under 70 (not easy) and have been pretty gentle on accelerating and decelerating (not fun). How long should I do this for? I seem to recall reading that this sort of gentle break-in is important for the first 500 miles or so of any new car, but honestly don't know if even that is accurate.

Thoughts?

DerwoodEE

I didn't ever hammer on the gas or anything. Actually, with 6,000 miles now, I've still barely ever gave it much.

I don't think I even bothered to keep it under 70 on the interstate though. There's not much of a difference in RPM speed from 65-80 anyways.

MrHeeltoe

iTrader: (1)

I don't wholeheartedly believe that break in "rules" are so critical. How you drive the car during break in should be representative of how you will drive the car on a normal basis.

kowloonsniperhk

Im no expert but I usually try to keep it under 4K RPM and to gently accelerate. Yet, there are times during the break in when I had to accelerate a little bit faster but its not really a problem.

One interesting theory that my friend, a Mechanic, said about the "breaking in" period. He said that by driving it hard at the begining helps the ECU "learn" about your driving habit, so that it adjusts.

LaserBoy

There are some folk out there in internet-land that say the best way to break in a new motor is to hammer it -hard. One site I found said 85% of redline. The idea is to generate as high of cylinder pressure as possible to seat the rings and scrape the fine honing marks off the cylinder bores. I think that is one of the reasons Acura does not ship with synthetic oil. Synthetic oil is almost too slick to allow this process to happen correctly.

I didn't have the guts to bury my foot in the gas that hard, but I did drive my new car pretty aggressively on my first few rides.

Like the others have said, there probably isn't one right or wrong way to break in a motor anymore. To be honest, many will have moved on by the time any real issues manifest themselves anyway.

SSFTSX

It is righter there under Maintainance/Other tab on owner.acura.com. It is pretty usefull site for routine maintiance.


In other words they dont say you cannot drive faster like 80 to 90 mph but just slowly built your speeds and slow deceleration.

09TSXMN

The other major element is to avoid constant throttle during the first 500 miles. Avoid the cruise control and constantly vary your speed. The reason is the piston will create a memory seat groove at the same speed. I am a full believer of no hard throttle during the break in time. I know my Mini Coop S states to keep it under 4K RPM for the first 800 miles as well. There has been documented evidence of higher oil consumption on the Mini engine and the Mitsi EVO that did not go through the break in properly. Honda 4 cylinder engines are notoriously known for their durability so probably are more forgiving, however, why push it? Don't forget the impact on the transmission and brakes as they are getting broken in at the same time.

xenonhid

Hope you don't think everything your mechanic tells you is accurate. You don't have to teach the ECU during the breaking in period by driving it hard which I wouldn't do to a new car by driving it hard during the break in period.

After the break in period you can disconnect the battery to reset the ECU so it can learn more spirited driving characteristics.

TheGoodGuy

First off drive normally, dont drive it like you stole it though.. but drive it normally, keep it under 4500 (below vtec), you will notice as you drive the engine gets smoother. I noticed mine that by the time 1000 miles came around it had gotten smoother and i slowly opened her up to the vtec zone.

What ever you do, do not sit on cruise and vary the rpm's especially the first 600-1000 miles. I did a lot of LA freeway driving so i easily did those first 1000 in like 2-3 weeks. Keep an eye on your oil level.

Now i have almost 5000 miles and i regularly hit vtec while getting on to the freeway and its smooth as ever. I cant wait to see what it would be like after my first oil change.

kowloonsniperhk

Nah, its just one of his crazy theories, I still drive it easy for the first 1000 miles.

HeavyDuty

Just drive it normally for the first 1000 miles or so (that is, how a normal person drives, not an enthusiast). If you have a manual trans, clutch break-in is muy importante along with the engine & brakes, etc.

09TSXMN

The ECU does not "learn and adjust" to your driving habits. The only thing it does is monitor your driving/temperatures/distance between stops, to determine the oil life, thats all.

JTso

iTrader: (2)

I think it's probably impossible to find one break-in procedure that can apply to all makes, models and driving styles. Also, the "suggested" break-in miles by Honda is merely a guidelines for new owners.

Here's an old thread on the subject. https://acurazine.com/forums/1g-tsx-2004-2008-124/engine-break-645938/

Here's another interesting thread with oil analysis results to show when an engine is reaching the end of the break-in cycle. https://acurazine.com/forums/1g-tsx-2004-2008-124/confused-about-oil-change-657796/

The ECU does adopt to certain settings base on readings of certain sensors, such as intake temp (IAT), coolant temp (ECT), and O2 sensor short-term-fuel trim, long-term fuel trim (STFT, LTFT). While some settings would change prior to warming up, other settings would change constantly during driving in normal mode (closed-loop) or wide-open-throttle (opened-loop). What's not made clear is what the ECU is actually "learning". The most obvious change and ECU learning that one can easily monitor is the fuel trims using an OBD2 scan tool. The ignition timing will most likely change as a result. However, if a change is being mapped to a "pre-determined" setting based on a certain sensor input, then it's not really learning.

kowloonsniperhk

like i said, it was his reasoning...i was just listening

kharateez

for the first 1000 miles or so, just keep below 3500 RPM and you should be fine.

jlukja

That's the thread that I read and the procedure I followed when I first got my TSX. I've had almost no oil burn, great mileage, and zero engine problems going on 40K miles.

LukeaTron

I hear this all the time and it just doesn't make any sense. What conditions in the combustion chamber are going to vary with RPM? I mean there are obviously differences but I can't understand how these differences could possibly translate into any sort of damage to the cylinder wall or piston rings. It'd be one thing if you're saying "don't cruise at 7,000 RPM" but I just don't see how sustaining a reasonable cruise rate could possibly harm anything.

melody

I've had the same thoughts as well... I don't quite get it either.

So far, I have about 900 miles on my TSX. Most of those miles were on the highway - I tried to vary the RPM by speeding up and slowing down, but really there's not much difference in RPM between 65 and 75 mph.

Also, I've done what was recommended in that other thread someone here pointed to - gradually increased RPM's before shifting (I have an AT, and I'm using SS). Today I pushed it the furthest yet, to about 6,000 in 1st and 6,000 in 2nd. I figure that if I'm "breaking in" this engine, I'd better run it at high RPM's, otherwise I'll have an engine that's only ever been run up to 4,000 RPM... doesn't sound like breaking it in to me!

Maybe we're all overthinking these things... ?? Is there anyone out there who's done something during the break-in period of a new car that, looking back on it, they realize they shouldn't have done as it ultimately had a negative impact on the engine? If so, please post the details as I'm interested to know...

CL6

The engines are so well designed today with such close tolerances that I think this is more of a parlor game than anything important. Breaking in the brakes only serves not to warp the rotors which are covered under warranty anyway although I would still not slam on the brakes.

TS_eXpeed

Well there was that one theory that you should run the car pretty much as hard as you possibly can the first 20 miles of the car. Supposedly it seals the rings in the cylinders.

There was a thread made about it in Car Talk a while back. There were even pictures that showed supposedly what the two engine look like after 'x' number of miles with his method, and with the factories suggested method.

If his method truly works, then his engines definitely looked better, but you can't always trust people I guess.

LukeaTron

That's a hugely over simplified version of the process known as MotoMan's Hard Break-In. Here's some info that's actually useful..

ttk5

in all honesty..i didnt break in my car at all...it really doesnt matter does it? i mean..how many people can accurately say that due to "not breaking in their car," something bad has happened

[R]isque'

Warm it up properly, then drive it like you stole it. The engines come 'broken in' from factory.....
I only bedded in the brakes, then drove how I normally drive.

LukeaTron

This is pretty much the truth of the matter these days. I think the biggest thing is following the first oil change schedule exactly as the manufacturer suggests. This is because a lot of crud ends up in the oil in the first few thousand miles. You want to leave the original oil, which is different and specifically formulated for the conditions of a new engine, in the engine long enough to do it's job but you don't want all that junk circulating through things longer than it needs to.

jlukja

In reality it probably doesn't matter. However, why not just follow the instructions provided by the vehicle manufacturer (as posted by SSFTSX in post #6 of this thread)? Its what is stated in the 2009 owners manual on page 356.

09TSXMN

The piston on the up and down stroke, particularly on the up stroke travel farther based upon RPM. Inertia plays a key roll. The constant RPM will hone in a line on the cylinder wall that may not be at top dead center when reving the engine higher. Yes, tolerances are better, which will help remove the "piston slap" issues of the older engine manufacturing processes, but the cylindar walls still get further honed during the break in period even on modern, Honda built engines.

LukeaTron

What the hell are you talking about? The piston might go a thousandth of an inch higher when it's swinging around harder but that's it. You've got the tolerances on the crank journals, crank to connecting rod and on the wrist pin and that's it. Do you honestly believe that the variation from low to high RPM in the amount of slack on those tolerances varies that much? I sure don't.

I can see how this might possibly be considered something to think about with older, sloppier manufacturing processes but with these engines, it's a total non-issue.

jlukja

Higher RPM means higher piston speed. If there is honing to be done on the piston rings the higher piston speeds will produce hotter hot spots which, if hot enough, may do some damage to the rings.

LukeaTron

I have doubts that the friction from the honing would be enough to burn the rings. You see burned rings when they've worn down to the point that you're getting continuous blow by.

Still, as I said earlier, it's probably not a good idea to hang around in the high RPMs on a brand new engine. That should be a no-brainer though.

Totally anecdotal and meaningless, but my friend's Subaru Legacy GT burns a good bit of oil and he completely babied that thing seemingly forever when he got it. I think it's mostly just the luck of the draw though, i.e. that engine was going to burn oil no matter how it was broken in.

JTso

iTrader: (2)

I believe it has to do with the cylinder pressure under heavier load condition to properly seat the rings. An engine running at steady rpm such as freeway cruising speed generates a lighter load condition.

LukeaTron

This makes sense and is why I don't think keeping the RPMs super low is all that good of thing. Two things increase cylinder pressure, engine load and/or what the ECU is doing. The way piston rings work (for those that don't know) is that there is a little groove on the back of the ring facing the top of the cylinder. This allows a little bit of the combustion gas to get behind the ring and push it outward against the cylinder wall. If it didn't have this feature, the drag from the cylinder wall would cause the ring to want to twist and only drag the edge of the ring up and down the wall as opposed to the entire sealing surface. This would cause a weak seal. When people talk cleaning out the top end of the engine with SeaFoam or whatever, what they're mainly trying to clean out is that gap behind the rings so that they can seal better and build up more cylinder pressure.

That said, by babying the engine, you are not pushing the rings out against the cylinder wall very hard and therefore not doing nearly as much honing. The process does generate a good amount of metal particles, most of which end up going out the exhaust. You need to be careful about how much heat you build up during this period because it can cause those metal particles to melt and then stick to things you don't want them to, like your valve seats.

So in conclusion, quick visits to the higher RPMs should help with bedding in the rings but staying up there too long can make a mess. I probably would wait until I've got a couple a hundred miles (a tank of gas or so) before doing this though as there's going to be some heavier particles coming off initially.

jlukja

To add to what Luke said... You don't need to necessarily redline the engine to increase cylinder pressure. You can put higher loads on the engine by going WOT at low engine rpms for short periods of time. That is one of the points made in the break-in process discussed in the thread by Clutch_Performer (see post #16 above).

09TSXMN

Ok, so I am showing my age, I had a new 1994 Blazer with a 4.3 v-6. At 40 miles I had to almost redline it to merge into the freeway without getting rear ended. The engine froze up. The mechanic told me that it was due to the high inertia on an unbroken engine and my piston "slapped" the upper cylinder, causing things to bend then break. It appears GM had a large problem with this in the early 90's due to manufacturing tolerance variations. He explained to me the importance of break in and no constant throttle. After some research, he is still right, however the reason of piston travel no longer applies because of the improved tolerances.

Go to this link as it explains very well the mechanics of the break in and the consequences: http://www.ntnoa.org/enginebreakin.htm

In summary, it says: The cross hatch honing on the cylinder walls must be flattened to allow the oil to complete a good bearing surface to the rings. Hard driving causes heat, which will "Glaze the surface", taking away the oil bearing. Constant throttle, resulting in light loading the engine, does not put enough force on the rings to flatten the cross hatch honing, the excessive oil left on the walls subsequently build up heat, which in turn "glazes the surface". The recommendation is to put loads on short, non frequent spurts, while at the same time not abuse the engine (to avoid heat build up on the walls) for the first 500 miles. The other element it states is to never abuse a cold engine, before having fun, run the motor for at least 10 minutes to get it properly warmed up.

Luketron, thanks for the challenge on my statement, I have learned more as a result.

LukeaTron

Heh, no problem. It's pretty wild that an engine that sloppy can even work at all. Then again, my dad was just telling me how all the army equipment he used to work on in the 70's had enormous tolerances. The idea was that it made things more fault tolerant. Apparently the diesel trucks were built so strong you could put just about any liquid that's even slightly combustible in the tank and they would run on it. Specifically he told me they used to parts cleaner as fuel occasionally. Of course an engine built with much heavier parts than required and huge sloppy tolerances throughout doesn't make a ton of power. The army answered that by simply putting engines that are twice as big as what should be required.

Anyway, ideally your cylinder walls will end up with the cross hatching still visible after they're broken in. This helps the walls retain a very thin coating (we're talking on the order of several molecules) of oil that act like microscopic ball bearings. The high molly steel they sleeve the cylinders with these days is pretty slippery in it's own right too. Half the reason the tolerances are so much tighter in modern engines is because the materials are so much stronger/harder/better. That and the computer controlled machines making the parts are far more consistent than one operated by a person.

TSXDriver23

Very interesting ways in breaking in a new TSX. I may try that with my new 09 TSX.

[R]isque'

The big diesels I work with glaze the bores on light or no load at constant RPM.
This could be why they want you to vary rpm during break in period?

[R]isque'

That is dead true. I ride dirtbikes, and tear into mine all the time. The Nikasil plating on bores now days lasts forever! The bore is always shiny looking and smooth, but you can see the cross hatching. They say you are in trouble when you cant see the hatch marks.....

nj2pa2nc

the break-in period of my 06 tsx consisted of driving the car from the dealer I bought it from in Pa to my home in NC (700 miles). I drove at different speeds, with or without the cruise control. I now have 68,000+problem free miles.

soon4tsx

I have seen cylinder bores with over 160K miles, and the cross hatch marks are still perfect. Some say the piston rings hydroplane on the oil film and only touch the cylinder walls at the ends of the stroke. That explains why a "ring ridge" can be felt at the top of the cylinder and why the rest of the cylinder has the factory made cross hatching fully intact.

LukeaTron

The ridge is carbon that builds up because it never gets scraped off by the rings. In most engines the top of the piston is almost completely level with the top of the block at TDC but the first ring is a bit below the top of the piston (this distance is called the piston shoulder). You will often see shinier part of the cylinder wall near the top and bottom and of the piston's travel (or more accurately, the rings'). This comes from the way rings flex when the piston changes directions. For a fraction of a second, the rings face is not flat against cylinder wall and just the edge touches. The ring stops floating on the oil film for that brief period and makes metal to metal contact with cylinder wall. It doesn't cause much damage though because the piston is barely moving at TDC and BDC. It's just a little kiss repeated several million times.