Pinging on deceleration

[CBRPilot]

Hi all,

I have a new 08 FJR and I notice that on deceleration many times (more noticably when cold) that there is very audible pinging. This happens on both 87 and 91 gas.

Tried a search but nothing really came up...

Anyone have any suggestions or similar issues?

Thanks!!!

 

[SkooterG]

I am not one of the resident experts, but I don't see how an engine 'pings' on decelration. It just won't be getting enough air, much less gas. Besides, the FJR's fuel injection is supposed to completely cut off the fuel on decel.

If your is pinging, there is something VERY wrong with your FJR. I seriously doubt that it is pinging. Are you sure it's not backfiring? Or popping?

 

[ionbeam]

One likely candidate to cause the noise you hear as pinging is the Air Injection System. When the engine is not up to full operating temperature (coolant thermostat is closed) air is injected into the exhaust ports, this also happens when the engine is warm and it is running at or near idle speed. The noise would be most noticeable when the engine is cold and running the cold enrichment FI map resulting in a lot of uncombusted hydrocarbons being burned via the air injection.

When the engine is cold, a solenoid allows fresh air from the air box to be presented to four reed valves in the cylinder head. Negative pressure pulses in the exhaust ports pull the reed valves open which inducts the air into the exhaust ports. Once the engine is warm (thermostat is open) the ECU supplies 12 volts to the solenoid shutting it OFF except for when the engine is at idle.

The next time you do a cold start, accelerate briskly then chop the throttle off. Does this cause the noise you have been hearing? If yes, you have identified the AI system as the cause.

 

[wfooshee]

And that noise would be a popping type sound, like an extra burbling. Not the "ping" that we identify as engine knock.

I agree that he's hearing the air injection.

CBRpilot, the air injection is an emmissions control device that reduces unburned hydrocarbons from the cold engine by feeding air into the exhaust. The hydrocarbons can then burn in the exhaust pipe, resulting in the popping sound, like muffled backfiring. It's normal.

A lot of guys remove it and plug the ports, which does no harm to the engine, and makes it easier to work on with all those hoses and jusk out of the way.

 

[SEA-FJR]

I was wondering about the same thing. I would describe it more as a crackling sound, almost like popcorn popping in a pot with the cover on. Glad to hear it's normal.

 

[fjr55]

I was wondering about the same thing. I would describe it more as a crackling sound, almost like popcorn popping in a pot with the cover on. Glad to hear it's normal.

DITTO!!!!!!

 

[CBRPilot]

I was wondering about the same thing. I would describe it more as a crackling sound, almost like popcorn popping in a pot with the cover on. Glad to hear it's normal.

Thanks to all for the replies. Yes SEAFJR is close to what it sounds like. I'd say it sounds like little tiny pebbles hitting metal. That's the sound coming from the engine.

Maybe it's normal as some of you has suggested. I'm going for a 600 mile service so I'll get it checked out then too.

Thanks again all!!

Jason

 

[ynotride]

Mine does it to. I think it has to do with the air injection emmision crap they throw on our cali bikes. There is a post somewhere on how to remove it and that is suppose to help with the ping. For now I am just living with it but I will probably remove mine on the next TBS.

 

[ynotride]

I found a post by Wicked Webby in the technical discussion section that shows you how to remove the air induction system to get rid of the popping. I dont know how to post a direct link but it is on page 6 right now.

By the way Thanks Wicked for putting that post together making it easy on all of us

 

[ionbeam]

<<Removal Procedure Link>>

 

[ynotride]

<<Removal Procedure Link>>

Thank you

 

[evilmedic13]

Pinging? Are you sure it's an FJR and not an ASW?

 

[ELP_JC]

And if you're as anal as me, it'd look like this after you're done:

But it doesn't have to look that pretty to achieve the same goal. Good luck.

JC