adorek24

i have an '04 accord ex 5-manual, stock. it has 65,000 trouble free miles on it and is my first honda. i plan to keep it for 200k miles and beyond.

i live on the east coast and for the past several years when the weather turns frigid the engine makes loud "clacking" sounds upon cold start-up which can clearly be heard in the cabin and which are quite unsettling. the clacking is loudest when the engine is under load, not so much at idle. it does not sound to me like valve tappets, which i had and were normal in my '92 protege, but more like an engine diesiling. if i take my foot off the gas and coast, i do not hear it. however in neutral, when i press on the gas, i hear it: "clack-clack-clack". it is loud enough to be heard over the radio.

while the temp gauge in the car starts moving after only a few minutes, the sound persists for a full 10-12 minutes, which is what i imagine might be the time it takes for the block to fully warm in freezing temperatures? i have not noticed any change in performance or fuel economy, but the sound of metal on metal makes me cringe and think, however irrationally, that i may be doing mechanical harm to the engine.

i change my own oil every 5k religiously, currently with pennzoil platinum 5w-20 and a pure1 filter, and have not run the engine low on oil. i have never added anything to the oil. i have, however, used gumout regane in the fuel tank several times, always prior to an oil change.

i've researched the web as best i can, but am still perplexed. some remark that this sound is normal for honda engines, others say it is piston knock, or valve noise, and still others, injector noise. truth is, i have no idea what the cause is but would love more information, especially if it leads to peace of mind.

any comments would be welcome and appreciated.

all the best.

trrbl1bmx

I work at a Honda Dealer here in Charleston, SC and I have had this complaint a couple times and Honda has released a service news about the oil pump/balance shaft assembly being noisy at cold start ( and other instances ). My recommendation to you is carry your car to a local honda dealer and request a shop foreman to look at your vehicle.

trrbl1bmx

Another thing I have seen is exhaust cam shafts with excessive wear, however, I have not seen this at the mileage you listed. I just replaced both camshafts, all rocker arms, timing chain, chain guides, and tensioner on an 03' with 230,000 miles. They are definatley good cars.

trrbl1bmx

Perhaps you could post a video to be certain?!

adorek24

thanks, trrbl1bmx, for the replies. the video is a great idea. utube it, then post a link here?

KWayRacing

The noisy oil pump balance shaft assy. problem only applies to 08- and certain 09 accords. What is true is that all Hondas experience piston slap and slight to defined valve noise at super cold start up. Piston slap is the pistons ability to rock inside the cylinder esp. towards the top of the bore. This is allowed by different expansion rates of the clinder liners compared to the pistons. There is a HOnda accesory block heater availible for yor car P/N 08T44-TA0-100. Since it is only temp related that is something you can semi control. I am interested in the video also.

MSchu

I'd like to hear this noise to... your description makes me think it may be related to fuel quality more than anything.

adorek24

kwayracing, your expertise is appreciated. i've had the block heater for about two years but have not noticed an appreciable difference in the quality of the sound or in the time it takes for the sound to go away. typically i have it connected for 20-40 minutes before i start the car. perhaps that is not enough time?

mschu, i use shell gas exclusively, which is the only top tier brand available in my area. when i first got the car i used mobil until i found out about top tier. i've never ever used off brand gas. i've used sunoco a few times when visiting upstate ny. pretty much shell only for the last several years.

PowerUser

20-40 minutes is nowhere near long enough to heat your engine block up. After reading over some threads on engine block heaters the general consensus is turn the engine block heater on no less then a hour and a half before you leave. Some people were recommending 2-3 hours if it's below 10F.