Very very strange clicking / ticking noise

[h.e.mujtaba]

Hey all,

I would request someone to please help me with the following issue.

I have got honda jazz 2006 CVT with 68000 miles (recently bought at 63000 miles). When I start and drive the car, the coolant temperature light is green which is perfectly fine as the engine is cold and there is no noise during this time. As soon as this light goes off (i.e. when engine is at normal operating temperature), I notice a tick tick (cricket metallic clicking) noise while accelerating and putting my foot on gas pedal. The harder I press the gas pedal, the ticking speed increase. This noise is noticeable from both inside and outside of the car and it feels it is coming from nearside lower front end. After 5 to 10mins of high rev driving, the noise goes away. This noise only comes when accelerating and does not come when car is standing.

Mechanic also failed to diagnose this. I feel that it might be coming from some component which is directly affected by temperature?

Tried putting high octane fuel, fuel injector cleaner and oil additive but nothing changed.

Please help

Thanks

[marcel]

You could try and jack up the car and rotate the front wheels by hand and check if the same sound is observed while driving. Could be parts of the brake assembly sticking and causing the pads to rub against the disc. Do you get these noises when you apply the brakes?

[h.e.mujtaba]

Thanks. Nope, no noise at all when applying the brakes. I still feel that this has something to do with temperature.

[sparky Paul]

I presume the frequency rises with engine speed, and not road speed. Could just be valve clearances need checking/adjusting. If it was tending towards a knock noise, I would suspect the beginnings of piston slap.

If the frequency rises with road speed, then it could be a CV joint, or a split boot. Test by turning slowly on both full locks, see if you hear the clicking.

Everything that is lubricated with oil or grease can be affected by temperature.

[h.e.mujtaba]

Thank you. I think it rises with engine speed and based on the history, valve clearance was never done. Not sure how knock sounds like which would give an indication of piston slap. Can you please guide me how knock sounds like? At 68000 miles, I doubt it could be piston slap as it is mostly found in high mileage cars. Thank you

[Jocko]

My engine ticks until it warms up. Valve clearances are designed to allow operation at high temperature so the clearance is quite wide when the engine is cold (unless you have an engine with hydraulic tappets. My engine has done 113,000 miles, and as far as I know has never had the valves adjusted. I have no intention of doing so, as all the reports I have read of people checking Jazz tappets find that they are pretty well spot on. If my engine gets noisy when hot, then I will check them.

[h.e.mujtaba]

This noise only generates when cold temperature light (green light) switches off. And the noise goes away after 5 to 10 mins of high rev driving afterwards

[David_B]

I literally just had the same issue and it turned out to be a stone stuck in the tyre tread. Drive with your window down and see where the sound is coming from and check the full circumference of the tyre tread for a stone wedged into the tread.

[sparky Paul]

It's most likely valve tappets, but these engines are prone to piston slap, even at lower mileages.

Tappets are usually rattly when cold, and you can hear them at tickover.

Piston slap is quieter when stood, noticeably louder when the engine is cold and under load, i.e. accelerating or labouring in high gear. There are examples of the noise on YouTube,  it's a knock but fairly light sounding - particularly from smaller engines. Like someone is tapping on the block with a screwdriver handle.

[h.e.mujtaba]

Thanks. This makes me tend to believe that it is piston slap rather than tappets and based on my understanding, there isn't any cure for piston slap?

[culzean]

Well both tappet noise and piston slap would be worse when engine is cold, they tend to go away as engine warms up.  Have you changed the plugs ( 8 of them ) the rear plugs on mk1 I-DSi engine tend to get ignored and can cause rough running and knocking / pinging under load.  The thing that changes when engine light goes off is that ECU will weaken the fuel / air mixture and this may cause pre-ignition knocking / pinking - which can be some times like a knocking rattling sound that appears when accelerating or under load up a hill.

[sparky Paul]

based on my understanding, there isn't any cure for piston slap?

No, but the engine will run for ever like that.

Culzean's suggestion is also worth exploring - pinking is also a possibility, but it's a different sound - sort of a metallic pinging, again on under load conditions.

It fits with the other symptoms though, you tend not to hear it until the engine has warmed slightly, then it can disappear as the injection system switches over to closed loop running as it warms up.

[h.e.mujtaba]

Thanks.  All spark plugs were replaced 4000 miles ago when full service was done and i have been using 99 octane fuel for sometime. Also used petrol system cleaner that should have treated pinking. Still the same

[VicW]

Years ago when engines needed decoking at regular intervals petrol system cleaner might have cured pinking.
With modern petrol and oil,decoking is a thing of the past so the cleaner would not have cured pinking.
Don't let the engine labour in high gears, let it rev a bit.

Vic.

[h.e.mujtaba]

Thanks.  And what about the effectiveness of premium fuel to cure engine pinking?