[hokiefyd]

I have a fairly well cared-for 2009 RTL with right at 100,000 miles. I know the original owner (my brother's father in law) and the truck's service history. The engine has a very repeatable spark knock/ping, and it occurs under certain conditions that I can easily repeat. I believe very strongly that this is spark knock and not the heat shield problem. (I don't think my VIN is included in the heat shield TSB anyway.)

I get a light-but-consistent knock when engine loads are above 80% (OBD-II engine load). At loads that high, the PCM removes EGR from the engine because combustion can become unstable at such a high load with inert gas. At this point, I believe it relies entirely on its preset spark mapping and the knock sensor to determine spark advance. I can watch engine load, spark advance, and EGR commanded/EGR error on my phone with Torque app and, again, I can very repeatedly call up knock by putting enough load on the engine that EGR % goes to 0% and I then begin to hear knock. So I don't believe I have an EGR problem -- the computer is actually calling for no EGR. It'd be one thing if it were calling for EGR and not getting it, but it's commanded the EGR valve closed under these conditions. So I don't think the EGR system plays into this at all (in terms of a bad EGR valve, EGR tubes being blocked, etc).

I do not have any current or stored codes in the computer. My question is, can a knock sensor get lazy and not report knock, and also not set a code at the same time? I've run a few tanks of premium fuel through it, and it doesn't seem to make a lick of difference. It will knock at higher engine loads, and immediately back off if I lift off the throttle (and EGR comes back in). I can apply more throttle, and as long as load stays low enough for EGR to persist, the knock stays away. It's almost like a "mode" or "phase" switch. I don't have a reliable way to determine if it's doing into fuel enrichment correctly. The highest fuel flow rate I've seen is about 14 gal/hr. Are my injectors actually delivering that? I don't know. After periods of heavier throttle, I do smell that "stinky catalytic converter" smell, so it seems that it is enrichening the mixture over normal.

Any ideas? There are few threads on here about spark knock, so it makes me think it's not "normal" and that I perhaps have a lazy knock sensor. My other vehicle is a 2005 Acura MDX with a very similar engine. That engine never has given us the first bit of knock, so I know these Honda engines CAN be knock-free. I'm just not sure what is normal for the newer engines (my 2009 has the newer J35Z5). Any ideas or comments are appreciated.

 

[mcmanut01]

Have you checked to see if a spark plug may be lose? Check the #5 plug(Middle plug up front) Good Luck.

 

[jberlin]

my o6 ridgeline had a ping that occurred under load with about 95,000 miles on it. I took the truck in at 99000 miles to get the timing belt and water pump done and the mechanic came out of the shop and showed me a coil pack that was oil soaked due to a bad spark plug well oil seal and was occasionally grounding out. I had an extended 100000 mile warranty and the coil pack was covered. It could also just be a bad coil.

 

[Geech08]

my o6 ridgeline had a ping that occurred under load with about 95,000 miles on it. I took the truck in at 99000 miles to get the timing belt and water pump done and the mechanic came out of the shop and showed me a coil pack that was oil soaked due to a bad spark plug well oil seal and was occasionally grounding out. I had an extended 100000 mile warranty and the coil pack was covered. It could also just be a bad coil.

Did just changing the coil pack fix the problem or was the spark plug well seal bad as well?

I have the same problem on a 09 with the coil plug soaked in oil.

 

[hokiefyd]

I have not yet changed any of the plugs or checked the coil packs. It just turned 100,000 miles, and had planned to do that along with the valve adjustment soon. I'll report back if I find anything amiss there.

 

[Geech08]

I think we have this problem with the spark plug well gasket. But I am not a mechanic.

https://youtu.be/wYU8qtPzQOY

 

[bulwnkl]

I had a Plymouth Neon years ago that would start knocking once the ECU went open-loop (relying only on preset maps for fuel, spark timing, etc.). If I'd back off the throttle a touch, enough for it to switch back to closed-loop, the knocking would instantly stop. It wasn't a heavy, detonation type of knock, but it was heavier and more distinct than the "light spark knock" that many, many owner's manuals mention as 'normal.' Never could eliminate the problem.

For the J35, what is the EGR valve condition at idle? Open or closed? What I'm getting at is: You know what the ECU is calling for in terms of EGR, but do you know what it's _getting_? I don't know what the valve's 'normal' or idle condition is, so I don't know whether a sticky one would cause the valve to stick somewhat open, or closed.

 

[hokiefyd]

For the J35, what is the EGR valve condition at idle? Open or closed? What I'm getting at is: You know what the ECU is calling for in terms of EGR, but do you know what it's _getting_? I don't know what the valve's 'normal' or idle condition is, so I don't know whether a sticky one would cause the valve to stick somewhat open, or closed.

The EGR valve position at idle is always closed. And it's always closed at WOT as well. The introduction of inert gas into the combustion chamber has benefits, but also has drawbacks, and a potentially unstable combustion is one of them. This is one of the reasons why it does not receive EGR at idle nor at WOT. It will generally receive EGR at most part throttle positions, but once engine load is high enough, it will close the EGR valve again.

You can monitor this on a vehicle that supports the EGR and EGR error PID through the OBD system. My 2009 Ridgeline supports both of these PIDs, but my 2005 Acura MDX supports neither of them. I don't know what Ridgeline model years prior to 2009 support them. The "EGR" PID is what the computer is commanding the EGR valve to do. If "EGR" reads 70%, then the computer is telling the valve to be open 70%. We don't yet know if it really is, but that's the commanded EGR position. The "EGR error" PID is the % difference between the commanded position and the actual position. Our EGR valves have an integrated EGR position sensor, and this PID reports the difference. For example, if "EGR" is 70% and "EGR error" is 0%, then the valve is 70% open. If "EGR" is 70% and "EGR error" is -5%, then the valve is 66.5% open. You'll generally see some EGR error during periods of transition, when the valve can't physically move fast enough to keep up with the computer. Periods of on-and-off the throttle produce a lot of EGR error, for instance, when the valve is trying to keep up with the changing commanded position.

When I hear the pinging, my EGR is 0% and EGR error is 0%. This means the computer is telling the valve to be closed and the valve actually IS closed. Again, it won't give EGR to the engine under periods of high load.

My question, my curiosity, is this: is what I'm hearing light enough for the computer to also recognize it and say, "yep, I hear the pinging, it's really light, and I'm going to allow it"? Or, is my knock sensor lazy and the computer doesn't really know the engine is pinging? It's a very high-pitched clink-clink type pinging -- not the low-toned heavy cluck-cluck sound of more severe knock.

If I haven't mentioned it before, the only reason this has really piqued my curiosity is our MDX's 3.5L engine is super quiet. No matter the octane we run, it's never exhibited the first ping or knock. So I know these Honda J-series engines CAN be quiet. Our MDX's engine has no spark plug well fouling at all. I have not yet changed the plugs on the Ridgeline or checked the coils. That's something I'm becoming more keen to do, though, along with the valve adjustment. I may go ahead and do that sooner rather than later, based on the suggestions in this thread.

 

[hokiefyd]

I think we have this problem with the spark plug well gasket. But I am not a mechanic.

https://youtu.be/wYU8qtPzQOY

I don't think the J-series engines use the same design. I think our spark plug tubes are pressed into the cylinder head at the bottom, and the only oil seal is at the top where the cam cover seals the top of the spark plug tube.

 

[Geech08]

I think we have this problem with the spark plug well gasket. But I am not a mechanic.

https://youtu.be/wYU8qtPzQOY

I don't think the J-series engines use the same design. I think our spark plug tubes are pressed into the cylinder head at the bottom, and the only oil seal is at the top where the cam cover seals the top of the spark plug tube.

Got it. Sounds like that makes the repair much easier.

Any chance you have a link to the engine diagram? Thanks

 

[hokiefyd]

If you have oil in the spark plug tube, repair should be relatively easy, yes -- it'll be the top oil seal, in the cylinder head cover. You have a good parts diagram in your other thread. Cheers!

 

[bulwnkl]

The EGR valve position at idle is always closed. And it's always closed at WOT as well. The introduction of inert gas into the combustion chamber has benefits, but also has drawbacks, and a potentially unstable combustion is one of them. This is one of the reasons why it does not receive EGR at idle nor at WOT. It will generally receive EGR at most part throttle positions, but once engine load is high enough, it will close the EGR valve again.

...


My question, my curiosity, is this: is what I'm hearing light enough for the computer to also recognize it and say, "yep, I hear the pinging, it's really light, and I'm going to allow it"? Or, is my knock sensor lazy and the computer doesn't really know the engine is pinging? It's a very high-pitched clink-clink type pinging -- not the low-toned heavy cluck-cluck sound of more severe knock.

If I haven't mentioned it before, the only reason this has really piqued my curiosity is our MDX's 3.5L engine is super quiet. No matter the octane we run, it's never exhibited the first ping or knock. So I know these Honda J-series engines CAN be quiet. Our MDX's engine has no spark plug well fouling at all. I have not yet changed the plugs on the Ridgeline or checked the coils. That's something I'm becoming more keen to do, though, along with the valve adjustment. I may go ahead and do that sooner rather than later, based on the suggestions in this thread.

Has the ECU gone open-loop when this happens?

It is absolutely the case that ECU programming allows 'light spark knock.' Anyone who tells you differently is either ignorant or worse.

 

[hokiefyd]

Has the ECU gone open-loop when this happens?

I can monitor that through Torque. Good question. I'll report back when I know.

It is absolutely the case that ECU programming allows 'light spark knock.' Anyone who tells you differently is either ignorant or worse.

I agree, but it does seem that some are more tolerant of light knock than others. Again, our MDX's engine (same basic Honda J-series 3.5L) is dead silent at all engine loads. I just want to make sure that the light knock I'm hearing in my Ridgeline is because the computer is allowing it rather than because of a mechanical problem.

I haven't yet seen a reply that says, "yeah, all of our Ridgelines have light pinging, it's normal".

 

[bulwnkl]

I _thought_ mine exhibited rather more moderate than light spark knock, but further analysis reveals that it's not that. There's something ...rattling?... that sounds a great deal like spark knock. However, since it does it even if I take my foot completely off the gas pedal, I think it's not knock.

 

[hokiefyd]

I found what I think is a good PID to monitor in Torque: Commanded Equivalence Ratio. The CER is essentially a multiplier to stochiometric that the computer is targeting. For example, under nearly all conditions, the CER is 1.0. That is, the target A/F ratio is stochiometric (14.7:1) x CER (1.0) = 14.7:1.

During most deceleration events, when the computer is cutting fuel, the timing advance goes straight to -10 degrees BTDC (which is 10 degrees ATDC) and the CER goes to 2.0 (which means its targeted A/F ratio is 29.4:1). I don't know if 2.0 is simply as high as it will read, or if it really is targeting "stochiometric x 2.0". If it's truly cutting ALL fuel during deceleration, you'd think the CER would be "infinity". But anyway...

The CER, under very heavy throttle (close to WOT), will change from 1.0 to 0.8, which means its target A/F ratio is 11.76. I think this indicates power enrichment. And, I didn't have a lot of opportunity to test this yesterday, but I think my light pinging goes away under power enrichment. The intake roar is already loud enough then, so it's hard to tell, but I do think it goes away, or subsides significantly.

My take-away from this is the system is tuned a little on the aggressive side in terms of spark advance, and it accepts some light pinging under certain conditions knowing that, at real heavy throttle, it'll go away with power enrichment. I will have to see if our MDX's computer supports this parameter. It may not (it doesn't support the EGR parameters). If it does, I'm keen to try to see if it either doesn't give quite as much spark advance, or perhaps it applies power enrichment a little sooner than the Ridgeline does. Maybe the Ridgeline's computer is just a touch more stingy with fuel.

 

[bulwnkl]

Good deal. I'm interested to hear what you find.

 

[Dnick]

I just skimmed the previous posts, and I am by no means an expert in this area, but I can't help but ask.... could this be a failed knock sensor??
I know that the cable to the knock sensor (under the intake manifold) sometimes gets cut by critters working around under there.
This "should" throw a code if it happens, but as I said, I can't help but ask.

 

[hokiefyd]

I just skimmed the previous posts, and I am by no means an expert in this area, but I can't help but ask.... could this be a failed knock sensor??
I know that the cable to the knock sensor (under the intake manifold) sometimes gets cut by critters working around under there.
This "should" throw a code if it happens, but as I said, I can't help but ask.

Well, that's what I'm wondering. And, unfortunately, knock counts are not a standard OBD-II reported parameter, so there's simply no way for me to test it myself (not without Honda's own diagnostic software, an oscilloscope, etc). It's not terribly expensive (about 30 bucks), and the thought has crossed my mind to simply replace it when I do the valve adjustment this winter, so I can cross that variable off my list.

I would think that the sensor (essentially a microphone) could get lazy and the computer wouldn't know about it. That doesn't seem to come up in internet searching, though, even about knock sensors in general. They seem to be either "good" or "bad", bad ones detectable by the computer by no response at all.

 

[breye]

I've never tried it but the the Torque App Pro has a Knock Detector.

 

[speedlever]

I didn't know that. Does it work on the old 9141-2 protocol or does it need the CANBus protocol to show that? (2006-2008 are 9141-2, 2009 and up are CANbus, I believe).

That is still a thorn in my flesh as per US law, the CANbus protocol is supposed to be on 2008 and newer MY vehicles. My 2008 has the old 9141-2 protocol and Honda will not respond to my requests for info about this.