Has any one noticed a knocking sound coming from the engine when it's first started and has not yet reached operating temp. It doesn't sound like the normal valve tick that all my Honda's have made (I hear that also). It' sounds like it's coming from a lower part of the motor. Once the engine has warmed the sound goes away.

 

If it isn't coming from the oil pan and more from the area at the lower part on the block it could be piston slap from too much clearance between th piston and cylinder wall.... It would take a lot of hard miles and poor lubrication for it to be that and there would probably be oil smoke coming out the exhaust pipe and oil accumulating in the air cleaner.

 

my car has 60k on it. no smoke, well maintained, no oil usage, no abuse. not sure what to think about this noise.

 

Interesting...
I've never had problems with "cold" temperatures as living in Texas - it gets cold like 4 days out of all 365...

However recently I heard of someone having "knocking" sounds when their gasoline is combusting before the spark-plug ignites it - of course this would require hotter temperatures and is a long-shot to impossible chance that is what ails your car... but just some input.

Very puzzling though, just go get your dealership to check it out - can't cost too much just for a diagnosis...

 

I think if you dig around you'll see some other posts about this a long time ago. Fit 1.5 makes not so pretty sounds when cold, but completely normal.

 

It could be a number of things from too low oil pressure. Have bigger oil filter or too thick oil (30 or 40 weight, for example). Or Crankshaft bearing 'leaking'.
You need experienced tech AND YOU NEED TO GET IT DOCUMENTED AT YOUR DEALER.

 

Where do you take your fit to be serviced? mahout makes a good point about the oil viscosity, most shops will not put 5w20 in unless you specifically ask for it, the most common oil viscosity currently used in shops i believe is 5w30 so give that a shot too and let us know how it goes

 

Hey guys, sorry for the old thread revival, but my wife's '08 has been experiencing the same rapping noise on cold start for the last 15000 miles or so (currently at 53000). It's a solid metal-on-metal rattle coming the middle of the engine that corresponds to engine RPM's. Once the engine is warm the noise disappears except between 2600-3000 rpms only. I've adjusted the valve clearances twice, changed the spark plugs, replaced the the EVAP purge valve and it hasn't changed anything. Just wondering if anyone else has experienced this issue, and possibly found a solution.

I took it to the dealership where we bought it because it's still under the powertrain warranty. Left it overnight and had the shop foreman listen at cold startup in the morning. He acknowledged the sound immediately and asked to keep the car for the day. At the end of the day the service advisor told me that they couldn't figure out what the sound was, but they think that it's normal because they started a bunch of other Fit's on the lot and they all had a similar rattle. He also said that the only way to find the source of the noise was to start replacing parts, which he warned would be very expensive for me. They tried to give me a bill that said that they could not reproduce the sound, and after much arguing, they gave me a second receipt and stapled it to the first one that stated that they acknowledged the sound but did not fix it.

Anyway, any advice would be much appreciated. Thanks!!

 

They heard the sound but wouldn't put in writing that they heard it until you argued? My advice would be to find another dealer.

 

I'm still clueless as to what this noise could be. The car now has 92K on it and pretty much makes the noise all the time now except when it's warm outside and the engine has been driven hard so it's good and warmed up. There's also a more recent thread called check out this noise that deals with a similar noise. You may want to check it out.

 

Its not normal in any of my engines. I would take it to be something with clearances too great when 'cold'. Crank bearing, piston pin, or piston / rings flopping.
next time you start the engine let it crank a few rpm and shut off to see if the knock changes with rpm.

 

I'm not sure what you mean by letting it crank a few rpm, then shutting it down. Explain more so I can try it. In all honesty, I'm not sure I'll ever know what this noise is unless I have someone tear the motor down.

 

a lot of us have had the same sound. i gave up on figuring it out haha, it's a mystery: https://www.fitfreak.net/forums/1st-...out-noise.html

 

It must be normal to have 92K and no other problems. Its probably the combustion of the fuel heard through the block. It might be only heard a one point because the aluminium is thinner there.

 

Helpful post! Thanks guys

 

It's similar to when I brought my car to the dealer after owning it for 2 1/2 years to show them the rust on the bottom inside of the door. The ass told me it was normal and that if i looked at the bottom of the door on all the cars in there lot at least half of them would have rust there. Now my car's almost five years old and all of the doors have a ton of rust at the bottom. I cant' find a dealer in Minneapolis that cares about customers.

 

The easiest way is while going downhill and leaving the engine in gear let the car slow down by itself and see if the knocking sound decreases as engine speed, which I predict it will when the engine is cold.
I suspect the knocking is due to the pistons 'flopping' at the top, bottom, or both of the compression stroke of one or more pistons. Its a result of less piston rings to reduce engine friction letting the piston flop in the cylinder when the stroke changes direction.
As the cylinder walls and piston warm up the flopping goes away and the sound with it. And I can't really see much harm to the engine in that case.
But if its loose piston rings or crankshaft clearances it would likely be harmful.
The best course is to document the sound yourself with a recording device and have a dealer document the presence of the knocking so that even after 50k miles you have a case for warranty repair. Reliable witnesses won't hurt either.
Have you tried contacting Honda directly from the contacts in your owner manual ?

 

Mahout, on my car the noise isn't present under load or while the car is being driven at all. If I start my car and let it idle it initially sounds fine. If I let the car continue to idle it'll start making the noise when the engine's warm enough for the idle to drop below 1000rpm's. Then, if I drive the car very aggressively so the engine reaches max operating temp it'll stop making this sound and will sound completely normal at idle. So basically, the noise is only present during idle and at the low range of what would be considered operating temperature.

 

Piston 'flopping' is present at light combustion load conditions at low rpm (certainly idle) at cold temperature. Once the piston is under real combustion loads which happens with higher rpm and acceleration loads the flopping ceases even if the temperature was low. Sounds like your case and others. I still say document, document, document..

 

Your description very accurately portrays my situation except for 'no noise under load'. On a cold start, my wife's engine doesn't make the 'rapping' noise until about 20-45 seconds after starting it. We normally let the engine warm up for about a minute or two before driving. The noise is there while driving and correlates with the engine speed, but after about 5 minutes it's almost imperceptible. If you stop and pop the hood after 5-10 minutes and listen at idle, there's no noise at all. BUT, there's a consistent point in the RPM range between 2600-3000 rpms where the noise comes back ONLY under load. It doesn't matter how warm the engine is, whenever you touch 2600 under load the metal rapping occurs until you hit 3000 rpm's then it gets quiet again. This is especially prevalent in 3rd & 4th gears.

I did see the other thread. I plan on getting a video here soon, I'll try to post it up in either of these threads this weekend sometime.