HELP!! Trying to track down the pinging source.

I’ve been trying to track down the source to the pinging sound on acceleration in my 2001 Honda Passport (V6). I did some research and came up with this (below); I’ve ruled out the 1st theory because I don’t have an overheating problem, and also the 4th theory because as I understand it the ignition timing on these year and type vehicles is computerized and is not manually adjustable. So that leaves me with the 2nd & 3rd theory. If I were to make an educated guess I think it would probably be the 3rd theory (EGR malfunction)……problem is….I can’t see nor do I know where the EGR is on my vehicle. I know it looks like a black can with some tubing and/or wires coming out of it. But, I can’t see anything like that nor do I know where to look…or even maybe this vehicle does not have one? Pictures would really help if not a general direction would be very helpful. Thanks in advance to all.

Pinging, knocking and detonation are all terms for a condition known as "pre-ignition". That means some of the gas and air mixture is igniting in the cylinder before it's supposed to. And when that extra flame front crashes into the normal flame front (created by the spark plug), you hear a noise, and that noise is pinging.

There are four major causes of pinging. The first three are related to excessive heat.

The first is severe engine overheating. If the engine is running too hot for any reason, the temperature in the cylinders can simply be too high. In that case, some of the mixture can ignite before the spark plug fires just from the intense heat.

The second major cause of pinging is carbon buildup inside the cylinders and on the pistons. When too much carbon collects, it can reduce the size of the cylinders (increasing the compression and temperature of the cylinder contents) and retain excessive heat itself.

The third cause of pinging is a malfunctioning exhaust gas recirculation (EGR) system. The EGR is supposed to send non-combustible exhaust gas into the cylinders to lower the temperature of the mixture.

How does 800-degree exhaust gas LOWER the temperature in the cylinders? Because it doesn't burn, and it crowds out some of the oxygen that would have burned and made an even hotter flame. And if that EGR is not working properly, the cylinder temperature can be too hot and the engine can ping.

And finally, incorrect ignition timing can cause pinging. The ignition timing determines when the spark plugs fire. And if they're set to fire too early, the stuff will begin to burn too early.

The use of higher-octane gas often makes the pinging stop because it has a higher ignition point. By requiring a higher temperature to make the gasoline burn, you reduce the likelihood of it "pre-igniting" somewhere else in the cylinder.

But premium gas doesn't address the underlying problem. So start by checking the EGR system, the cooling system and the ignition timing. And if none of those things fix it, then you can consider using a higher-octane fuel.

A pinging 1998+ is a stubborn mofo to troubleshoot. EGR shuts off on hard acceleration, so that's pretty much out of the picture. 2000+ 3.2/3.5's have electronic throttle control and a pretty involved ion sensing coil over ignition system, so any issues there will throw a code. If it were mine, I'd run some chevron techron concentrate, fuel power or lucas UCL, and do a spray cleaning of the MAF, throttle body, EGR and PCV and IAT sensor. Still pinging heavily after that, I'd order a new set of denso sprark plugs from sparkplugs.com. Still pinging after that? Let it be. I've yet to hear of a melted piston top on a 3.2/3.5 anyway.

Joel

change the plugs recently?

I took the EGR off and took a look at it. It seemed to be in good working order, the intake valve was free and clear..had a little builtup carbon on it but is still move nice and smooth. I'm still going to clean it out with some carb cleaner just in case. After that I looked around in the forum some more and ran across the sparkplug issue. I havn't changed the plugs in quite a while, so I went down to the local auto parts store and got some NGK Iridium IX (BKR5EIX-11). I hope these are the right kinda plugs...because the where $7 a pop. One more thing, would like to clean out the MAF, throttle body, EGR and PCV and IAT sensor. Can your give me a pointer on where these are located please. Thanks again for all the help.

I would also think about dumping a bottle of techron concentrate int he gas and 1/2 a bottle of sea foam in the oil (right before you change the oil, put sea foam in and then take it for a short 20 minute drive and then change the oil).

The main thing that causes ping is the carbon build-up. If you take a look at your tail pipe you will notice the carbon build up on it.

-Ryan

Update: Changed the spark plugs, cleaned the EGR, Cleaned the PCV valve. Took it for a drive...:( I still have the dang valves clattering and clinging. The car drives well on take off but as soon as I get to about 35-40mph it starts pinging again. Also took it on the highway....does good....as long as you don't accelerate or go over a hill. As soon as the vehicle is accelerated or goes over a hill the valves spaz-out they cling, clatter and pings like a whiney B....th.

It's not the valves, it's spark knock/detonation you are hearing. I'd get a spray can of electronics cleaner (autozone sells CRC brand) and spray clean the MAF sensor and intake air temp/IAT sensor. Those two sensors can throw off the fuel trim just enough to cause a less than ideal air/fuel ratio. That condition could cause an audible ping as well.

Joel

and if it's as bad as you're making out...i'd get it resolved sooner than later.
mild occasional pinging is one thing, raucous ongoing pinging is another and can end up harming your engine.,

.//bc

My '97 Rodeo 3.2L pinged for years; from the 1st day I drove it off the lot new. Did everything - plugs, filters, fuel additives, higher fuel octane, dealership even flashed the computer 4 times, pcv valve, you name it, we tried it.

For over 5yrs the truck ran with a ping at the slightest edge of throttle; out of pure luck we found what it likes = higher altitude. Sounds weird, I know, but the weekend we moved ourselves back to Colorado, that truck stopped pinging exactly half-way through Utah.

Been back here almost 6yrs now, truck has 164k miles and hasn't skipped a beat, the pinging for 5yrs/70k miles doesn't seem to have any long-term effect on my engine. Hasn't pinged a single 2nd in 6yrs.

Don't know what to tell you - as I never found an actual resolution when I was living at sea level; and you can't tell me that a new truck has enough carbon build-up to cause a pinging issue.

I found this web page that has info on the rodeos.

Engine noise: Ticking noise from the top of 3.2L V6 engine may be due to hydraulic lash adjuster failure caused by varnish deposits and using 0W-30 Mobil I synthetic oil has been successful in cleaning them. (1997-earlier)

If you are interested in reading the whole review here is the link. Good luck.

http://auto.consumerguide.com/Auto/Used/reviews/full/index.cfm/id/2185/act/usedcarreviewshowall/

PS. I have the same noise coming from the engine but I just found this info. I'll change my oil next time and will let you guys know how it went with the ticking.:popcorn:

...Ticking noise from the top of 3.2L V6 engine may be due to hydraulic lash adjuster failure caused by varnish deposits and using 0W-30 Mobil I synthetic oil has been successful in cleaning them. (1997-earlier)..

The original poster has a 2001 3.2L. Totally different top end than the <1997. No HLA's.

Joel

...
For over 5yrs the truck ran with a ping at the slightest edge of throttle; out of pure luck we found what it likes = higher altitude. Sounds weird, I know, but the weekend we moved ourselves back to Colorado, that truck stopped pinging exactly half-way through Utah. .....

well assuming it wan't the mormon influence half way through utah, i'd be inclined to think that the ManifoldAbsolutePressure (MAP) sensor was at fault (did yours have one?) or whatever other component measures altitude (barometric pressure) to help the computer in adjusting timing and fuel, etc. of course, maybe the computer was programmed weird, too.

maybe that's something to check out in this case...(?)

I"ll be more then happy to clean out the "MAF sensor" and the "intake air temp/IAT sensor" I know the rough loacation of these compnents but could some one point me in the right direction. A short discription on how they look and where they are located will be much appriciated. As pay back I will take a pic of all these components and post them, so other may benefit. Thanks again.

Real easy. The MAF and IAT sensor are the only two items in the air intake hose between the airfilter box and the throttle body. As far as I know, there is no MAP sensor on the 1998+ 3.2's.

Joel

well assuming it wan't the mormon influence half way through utah, i'd be inclined to think that the ManifoldAbsolutePressure (MAP) sensor was at fault (did yours have one?) or whatever other component measures altitude (barometric pressure) to help the computer in adjusting timing and fuel, etc. of course, maybe the computer was programmed weird, too.

maybe that's something to check out in this case...(?)

Funny that you mention the MAP sensor; was just wondering earlier if that's had something to do with it's previous years of pinging.

Now that you added to that thought - the pinging as well as my current EGR issue - wonder if I've had a tempermental MAP this whole time.

Went back through ALL my paperwork, there's never once been the mention of testing the MAP sensor - even in warranty.

We'll find out tomorrow; Napa has one available too, if we find ours is faulty.

To the original poster...

Have you changed the fuel filter? A dirty one will restrict the flow of gas to the injectors, giving less of a shot into the intake, causing a lean condition, resulting in a slight to moderate ping. All this sounds good in theory, but I'm gonna try it out myself, as I'm trying to de-ping ours as well.

Well as it stands now I've done the following: Cleaned....EGR, Checked and cleaned the Mass Air Flow (MAF) Sensor, Change the sparkplugs, Check and cleaned the air filter (K&N), Checked and cleaned the PVC valve. And, after all this "still" pings the same. I've finally gave in and put in some mid-grade gas....it seemed to reduce the pinging about 50%. But I'd wonder why it pings with just regular standard unleaded? Maybe because of the oxygenation that the feds add to it during the summer months for cleaner exhaust? Therefore reducing its performance? I'd hate to think that these motors are such sissy's when it comes to small fuel production changes. "Still Stumped" :(

my 02 Rodeo had a bad ping when accelerating. Had fuel filter, air filter and PVC changed and ping was gone.

the next step is adding a bottle of techron concentrate to the gas and run most of the tank out. Then add 1/2 bottle of sea foam. drive it for 20 minutes and then change the oil. The first time I did sea foam I drove it for about 150 miles and then changed the oil.

You ping is most likely due to carbon build up.

Hey Ryan, did you put the Seafoam in the oil, gas, or intake?

I just dump a half can in the oil.

make sure the heat shields & clamps on the exhaust between the manifolds & the muffler arent rusted. my 98 has partially rusted shields & it clattered its ass off & drove me nuts.all the time i thought it was valves. GO FIGURE!