Tapping Engine Noise on Cold Start

nuodyowner · Oct 29, 2004

Anyone encountered this - on cold starts, especially in cold weather - I hear a tapping noise in the engine compartment on light acceleration or gas. Its speed increases or decreases with the RPM. After a 1 mile warm-up it totally disappears and will not occur again until the engine is totally cold.

My Ody has less that 9k on it so I don’t think it is any wear and tear. I suspect that it is normal fuel injector noise, which can make noise until they are warm.

I’m just curious as to whether this is common or abnormal, since I’ve seen no mention of it from other owners.

Igobuk · Oct 30, 2004

It sounds like enough oil isn't getting up the valves and that's the tapping noise. You might check the oil level and make sure the oil in there is the right viscosity.

Also, Purolator makes an oil filter with an anti-drain back valve. It's called PureOne and it's shiny metallic blue in a light grey box. It will keep the oil from draining back into the oil pan once the engine is off, so next time you start the Ody, the oil will still be up in the valves area. It helps protect against dry-start which sounds like what you're having.

egads · Oct 30, 2004

Who and when was the oil changed? It is important to put in 5w to stop cold start tapping. Honda recommends 5-20, but 5-30 is fine. 10-30 will cause the tapping. Anyone can change the oil, but the competent will make sure the specs are right.

nuodyowner · Oct 31, 2004

egads said:
Who and when was the oil changed? It is important to put in 5w to stop cold start tapping. Honda recommends 5-20, but 5-30 is fine. 10-30 will cause the tapping. Anyone can change the oil, but the competent will make sure the specs are right.

All my oil changes have been done by Honda, at 3600 and 7500 miles, (Dealer recommendation) but that doesn't mean that the dealer is following spec on the grade of oil.

I reason I'm asking whether this is common with others, was because I've noticed this since new and with the original oil. Which I presume was 5w from the factory. Which was also why I thought i might be injector noise rather than valve tap.

I presume from your responses that you have not experienced this or is it that you have experienced this and the oil grade is the solution?

egads · Oct 31, 2004

Well, I did experience it, but in a different vehicle (89 & 96 MPV) But it would apply to many vehicles now made. The passages for the oil are very small. So I just threw that out as a possibility. Tapping injectors? That's a new one to me. Report back if you get it checked out.

Grand Total · Oct 31, 2004

nuodyowner said:
Anyone encountered this - on cold starts, especially in cold weather - I hear a tapping noise in the engine compartment on light acceleration or gas. Its speed increases or decreases with the RPM. After a 1 mile warm-up it totally disappears and will not occur again until the engine is totally cold.

My guess from your description is that it is piston slap.

egads · Nov 1, 2004

Well, I thought about this today and even though if mine made these noises at only 9k I would be at the dealer asap, I do remember many Hondas in my friends and my own lives that made a lot of noise when cold and still did over 200k without any engine problems.

I just realized you did dump out the break-in oil a little early. When you do take it in you might mention to your dealer that even though he makes money on oil changes, from now on you would like to maintain your vehicle with Hondas' recommendations not his.

I know I'm risking turning this into a "how soon to change out the break-in oil" thread, but why would Honda recommend against early replacement for no reason?

Guest · Nov 1, 2004

egads said:
. . . but why would Honda recommend against early replacement for no reason?

Because they are not allowed to claim the CAFE allowance for fuel economy gains by using the thinner oil unless they coerce the owner to continue to use that oil for a certain length of time.

Wayne

egads · Nov 1, 2004

But what about the panther tinkle?

Robbie · Nov 1, 2004

I have noticed injector noise when a fuel injected vehicle is cold. It has a 'snapping' sound rather than a 'clicking' noise that is characteristic of 'tappet' clearances and disappears within a minute or two. It seems to vary depending on the motor. It's wise to remember that an engine is designed to work at normal operating temperature and when very cold the clearances caused by cold temperatures may cause noises but these disappear when the engine starts to warm up and the metal parts expand. It's unlikely that it's piston or bearing noise due to the grade of oil but nevertheless I always use 5/30 grade since I feel the requirement for 5/20 is based on CAFE fuel economy which doesn't apply in Canada. (Did you know that Canada is the largest supplier of oil to the U.S.?)

Guest · Nov 1, 2004

egads said:
But what about the panther tinkle?

Uhh, uhh, I think Jerry O's the resident expert on that stuff. I never indulge!

:stupid:

Wayne

tinkerer · Nov 1, 2004

egads said:
Who and when was the oil changed? It is important to put in 5w to stop cold start tapping. Honda recommends 5-20, but 5-30 is fine. 10-30 will cause the tapping. Anyone can change the oil, but the competent will make sure the specs are right.

Just to make things more interesting for y'all:

Oddly, depending on the engine and the particular oil, it may be important to NOT use 5W, but rather, 10W, to stop cold engine tapping.

My other vehicle (a Toyota product, 4.7L V8) will exhibit cold tapping (valve lash) if I use 5W-30 Mobil 1, but there absolutely NO cold valve lash tapping if I use 10W-30 Mobil 1 synthetic.

Someone else asked me this, and it turns out he also has this experience, with a different engine/vehicle (GM product), using Mobil 1 synthetic.

So, it's not just me.

Synthetic oil has better cold flow properties than petroleum-based oil, so it may not compare directly to regular oil, regarding this issue.

I believe that compared to petroleum-based oil 5W-30 (and the synthetic 10W-30), the synthetic 5W-30 oil drains away more fully from the upper engine components, including the valvetrain clearance areas, when sitting overnight. So when the cold engine using synthetic 5W is started, the valvetrain has less residual oil coating the contact parts (follower-to-cam, rocker-to-valve actuator, depending on design, etc.), and therefore, those parts make more noise for a minute or so, until they both (a) become re-coated with oil within the contact clearances, and also (b) expand to reduce clearances.

(All of the above assuming NOT a hydraulic lifter design valvetrain. If hydraulic lifters are used - there are other issues.)

(And yes, I always use a filter with an anti-drainback valve.)

Fuel economy is apparently the same, whether 5W-30 or 10W-30 Mobil 1, in my Toyota-built thingy.

Anyway, when I started using 10W synthetic instead of 5W synthetic, the problem went away.

We'll see what happens with the Ody.

timmckinstry · Nov 1, 2004

I had similar sounds at around 31000 miles. My mechanic suggested it might be a ignition/plug wire issue, but the sound is sporadic so I am going to wait.

nuodyowner said:
Anyone encountered this - on cold starts, especially in cold weather - I hear a tapping noise in the engine compartment on light acceleration or gas. Its speed increases or decreases with the RPM. After a 1 mile warm-up it totally disappears and will not occur again until the engine is totally cold.

My Ody has less that 9k on it so I don’t think it is any wear and tear. I suspect that it is normal fuel injector noise, which can make noise until they are warm.

I’m just curious as to whether this is common or abnormal, since I’ve seen no mention of it from other owners.

nuodyowner · Nov 3, 2004

Thanks for the feedback.

I'm aware that dealers push for an early oil change for the xtra $. I went with it because we do a lot of short hop trips, which I thought would put us in the “sever” conditions category. That first 3600 miles was after 9 months of use.

On the tapping issue, I did a check tonight and noticed that the noise would continue for about 5-10 minutes – most noticeable when I give the engine gas, but not during idle. Even after the engine temp has rising to over the 1/3 mark the noise lessens but is still there. I would presume that by then the oil is warm enough to have coated the entire engine. After parking, a few minutes and restarting the noise disappears.

The noise is more of a dull snap than click. What is the potential that this is PCG valve clicking away?

tinkerer · Nov 3, 2004

It's dicy trying to troubleshoot vehicle noises and problems based on written or spoken descriptions only.

Best is to get a good mechanic to listen.

Good luck.

EricD · Nov 4, 2004

Grand Total is right, it sounds like piston slap. This is from Honda Service News March 00.

Cold Start Knock
To some degree, cold start knock (piston slap) is a
normal characteristic on 4-stroke gasoline engines. It
happens when the engine is cold (piston-to-cylinder
clearance at its greatest, and most of the oil has
drained back into the pan). As the engine warms up,
the knock should quickly diminish, usually within 2
to 3 minutes.

Eric

nuodyowner · Nov 5, 2004

EricD said:
Grand Total is right, it sounds like piston slap. This is from Honda Service News March 00.

Cold Start Knock
To some degree, cold start knock (piston slap) is a
normal characteristic on 4-stroke gasoline engines. It
happens when the engine is cold (piston-to-cylinder
clearance at its greatest, and most of the oil has
drained back into the pan). As the engine warms up,
the knock should quickly diminish, usually within 2
to 3 minutes.

Eric

Thanks for the info - I'm going in for a check up soon. If the mechanic says this is normal for a Ody with only 9k on th odometer, should I accept that?

Pertina · Jan 26, 2005

I have the same problem on cold days. But once the engine is warmed up it goes away. I like to try to warm up the engine for a couple of minutes before taking off. It just doesn't seem right, to me, if the engine is tapping to drive until it starts to go away. Seems like more stress on the engine. I asked the dealer what type of oil they recommend for this time of year and he said 5w-20. I don't go to the dealer for oil changes because they are too expensive. I go to Firestone and they use Kendall. I am asking him to put in 5w-20 today (extra cost - of course) and see if it makes a difference.

Maria

nuodyowner · Jan 27, 2005

Thanks for the reply - let me know if the thicker oil does the trick

babylon5 · Jan 27, 2005

Thinner, no thicker...

nuodyowner said:
Thanks for the reply - let me know if the thicker oil does the trick

I gather you meant thinner oil? Thibker oil won't help
anything related to cold weather valce or piston slap noise.

A thinnner oil lile 0W20 Mobil 1 will DEFINETLY help if the
noise is due to insufficent lubrication when cold.
As far as piston slap this won't be solved by oil. This is due to the
clearance between the pistion and the cylinder walls. When the pistons warm up and expand the noise will go away. On the 350
chevy I had built up I replace the regular cast pistons with
TRW forged ones and due to that fact that forged pistons
expand more than cast ones you have to use a larger cold
clearance. They were definetly noisier when cold.

Tapping Engine Noise on Cold Start

nuodyowner

Igobuk

egads

nuodyowner

egads

Grand Total

egads

Guest

egads

Robbie

Guest

tinkerer

timmckinstry

nuodyowner

tinkerer

EricD

nuodyowner

Pertina

nuodyowner

babylon5

Top Contributors this Month

Recommended Communities