HI all, figured I would post in the Ram truck section since i couldn't get a good answer in the Durango section. I am pretty sure the second generation rams have the same 5.9 and my 2001 Durango R/T. I have a bad sound coming from the engine when going uphill and/or under load. I can only seem to duplicate it when I am going up inclines somewhere above 45 mph, if I let off the gas the sound goes away even if I am still on the hill. My Durango has a little over 108k and I just did the plenum gasket fix (I went with the thicker plate install) I thought this was going to be the cause of the noise, figured it was pinging. I just did a the plenum fix, new plugs, new rotor, new front oxygen sensor and new timing chain. My water pump is only about 6 months old. Here is a clip of the sound, you can hear it really well because the wall is bouncing it back. I cleaned the intake keg and cleaned my fuel injectors as well. Only thing I haven't done is run seafoam spray in the throttle to see if maybe its carbon build up inside the cylinders. Other thoughts include my left front wheel bearing is going out? But why would that only make noise going uphills. Hoping someone has some thoughts...

 

Hows the power curve, is she responsive? Is the money light on? Does your exhaust sound like a hiss as opposed to deep n throaty when you rev the engine? Try sitting on level ground n put your foot into the throttle, does she still do this on level ground? Have you tried higher octane gas? Using a different gas station to fill up with? My thinking leads me towards broken-clogged cat/s if your pretty sure there's detonation. Have an exhaust shop check your cat/s for back pressure. If not, invest in an automotive temp sensor and live data reading scanner. Read the temp difference between the front n rear of your cat/s...is it the same or at least 100 degrees hotter AT THE EXHAUST side, not the entry side. Have you checked your plugs, whats their condition? Especially the #8 plug with 1 cat...add #7 to the mix with dual cats. Get a scanner that reads live data and note certain parameters like timing/fuel trim/O2 sensor/s...especially see how the downstream sensors are acting...are they rock steady or moving up n down like the upstreams?

 

True blue thanks for the reply and suggestions. No check engine light is on. Revved the engine today a few times up to 3000 rpm didn't hear anything out of the norm. Engine feels very responsive and exhaust sounds mean and loud. Previous owner had a flow master so it always sounds beefy. I filled up today with mid-grade so I will report back. I always use Exxon and not no name gas. Did you happen to check out the video? That sound is pretty distinct but I am not sure if that what pinging sounds like.

I actually found out about the plenum issue when I did my plugs over the summer. My 8 and 7 plugs were a bit hard to take out, when I got them out I noticed that the threads had gunky oil on them. The valve covers leak a bit of oil so I figured that they were dripping oil on the plug threads, I was also burning oil after my first synthetic oil change. So eventually I found out its the plenum issue. So the plugs I have in there now are relatively new along with the plug wires and distributor.

I have access to a witech scanner so I can check the o2 sensors. I saw a video on youtube on checking for a bad catalytic converter. The guy said the front o2 sensor should fluctuate a lot and the back one shouldn't and should stay around .50 volts or so. I don't think the scanner shows the temperature reading just the volts. I also have a infrared thermometer so I can check the front and rear temperatures of the catalytic tomorrow after going on the highway. Apparently the rear should be at least 20f hotter then the front. But you are saying it should be more like a 100 degree hotter in the after the cat? I will check that out tomorrow as well.

 

Yes, I did watch your vid, but it's difficult to diagnose such a sound with its inherant restrictions. It's kinda like using a blurry icehouse vid to arrest/convict a suspected robber, ya know? To be fair, with a 100% proper working cat, the exhaust side of the cat should be around 100 degrees hotter, but even if it's the same as the inlet (make sure you're aiming at the same type/thickness metal on the cat for both entry/exit measure) that only means that the cat is no longer cat'ing (catalyst is shot) BUT!!!, the engine can still operate just fine. The downstream O2 acting just like the upstream will tell this one. "IF" the cat is clogged, the entry side is usually much hotter than the exhaust side. These old ECMs don't measure cat temp because the only temp sensing of the O2 sensors comes thru the preheating probe to make the ECM go into closed loop faster. Don't worry too much about the "voltage" values, 'cause depending on the O2 sensor, that can change as well. That's why I gave no value, but condition. Fuel trims, O2 sensor n timing advance readings will tell lots about your problem if it's pinging. You can do a cursory check on those in your driveway. Check them at idle, 1500/2500 RPM...note them, then go driving and record (depending on your scanner, the more "mondo" priced scanners...it's a technical term...can record a live graph style feed for review later). Do this recording only when the engine is at normal operating temps. Note fuel trims, O2s/upstream n down and timing values especially when pinging occurs. N...just for giggles, your coolant and intake air temp (intake should be around 10-20 degrees warmer than ambient), so make note of that as well (intake air temp tells the ECM lots about the preset and ideal stoiciometric/mixture ratio...which can effect, guess what, detonation!) Lotsa guys with these Jurassic engines, run cooler t'stats so as to keep down the pinging, it's an old mechanics trick. You get an old high mileage engine, n between the inevitable carbon buildup and just plain 'ol wear, n ever crappier fuels designed for newer engines, the unfortunate result is an ever degraded performance of our old iron beast with minimal ECM intrusion. Thus endeth my rant...good luck.

 

Detonation is causing the "pinging" you are hearing under load. A couple things to try, like mentioned, a cooler t-stat, 180 deg. Though you should have a tuner to change the ECM parameters or it wont make as much of a difference.
Get cooler spark plugs, autolite 3923 (i believe) or Champion rc11y or even rc10y. I think Champion RC12s are what came factory. The idea is to go a point or 2 cooler. Whichever brand you choose stay with good old copper plugs.
You can also run premium fuel (91oct) and/or octane booster for a couple tanks just to verify that the sound does go away.
Post up you results,
Good luck!

 

Thanks for all the feedback fella's (learning a lot). This weekend I filled up the tank with Exxon 91 octane as recommended, it was already at about half mid grade (89, normally I run regular 87 but trying to find what the ping cause is). Took a 60 mile trip, no pinging at all! The following day on the way back I took the same hill where I noticed the pinging the first time (before I fixed the plenum issue), no ping at all. So this pretty much confirms "detonation".

3 months ago (before I found out about the plenum oil leak) I did a tune up and put AUTOLITE XP5224 {#XP5224DP2} Iridium plugs. Looking at what jlake4130 mentioned, now I am thinking I will have to change my plugs again (Label under the hood says Champion RC12LC4). Apparently Iridium's don't dissipate heat as well as copper. I found a big thread on spark plugs in the ram forum.

This morning when I started the truck I got a misfire code from cylinder #8 P0308. I am wondering if the higher octane somehow triggered this. I haven't had any codes till this morning since taking my trip and returning. I am going to hook my scanner this week and take a data log of my trip and I will post back.

I aimed my thermo laser at the metal pipe at the same spots on the front and rear (reading should be solid). I couldn't find consensus on this for all vehicles (That it should be 100) warmer.

The truck also has one of the cold air intakes, the ones like the K&N except it doesn't have the plastic bezel in the front. All this pinging and spark has me wondering about the air going into the intake and what effects it could have as well now.

 

I would change the plugs before heading back. I wouldn't be surprised if a fair few of your issues didn't go away.

 

You mean to change my plug before I drive the truck anymore? Could those iridium's I have in there for a few months cause an engine issue?

On the spark plug note, specs say RC12LC4 which according to that spark plug thread are a bit longer, should I just go stock or get something cooler? Not sure how to figure out what plug is cooler and the same style/fit.

 

I would change them out before putting a bunch of miles on it at once. The rare-earth plugs have been known to be problematic in these trucks.

Going a heat range cooler probably wouldn't hurt you..... if you can find a decent parts guy, he should be able to tell you the correct plug. I generally just go with stock though, even on my 200K mile plus truck.

 

Time to dig this up again:


Dodge Ram Magnum engines have gained a reputation for persistent engine ping. Many people have been working to solve the problem (some with success) and posting thair findings to the DiRT list. Here are some of the excerpts:

What causes ping?

One of the results of all the years of detonation research is this - when you compress a gas, both the pressure and temperature go up. At a high enough compression you begin to get pinging.
Is it the higher temperature - or the higher pressure - or both - that causes the ping? The answer turned out to be that it is mostly the higher temperature of the last bit of mixture that burns - the so called 'end gas.' The end gas needs to be kept less than about 1900 degrees. Pressure doesn't seem to matter much. This is the discovery that led to fitting intercoolers to turbo/superchargers. Intercooling is a way to partially compress - then cool - then compress the rest of the way. A supercharger that gives you 15 psi of boost is like a compression ratio of 2x. If you then feed this 2x into a cylinder with a compression ratio of 7, it is like you had a total compression of 2 x 7 = 14. This will work without pinging, but if you tried to run an engine with a compression ratio of 14 to begin with, it would almost surely ping. If interested, you can read about this in "The Internal Combustion Engine in Theory and Practice, vol 2" by CF Taylor on page 59. ISBN 0-262-70027-1 That whole chapter is about 50 years of research at MIT on how to reduce pinging.

There is mostly bad news about part-throttle operation and pinging.

The O2 sensor and the PCM try to control the air/fuel mixture at 14.7 air to 1 when you are driving around at less than full throttle. This is because the catalytic converter needs the air/fuel mixture to fluctuate back and forth near 14.7 to 1 mixture so that the cat converter can reduce the three bad things: NOx, HC, and CO. Unfortunately, 14.7 to 1 mixture IS THE ABSOLUTE WORSE MIXTURE FOR CAUSING PINGING but it is the mixture that the engine has to run at for pollution control. 14.7 is where the temperature of the gases in the cylinder, and the speed of the combustion are highest. Even if your MAP sensor or IAT sensors are off a little, it doesn't matter at part-throttle, because the O2 sensor will constantly 'self-correct' to the 14.7 range. If it pings less at full throttle, then that means that your PCM is correctly enriching the mixture. So to get rid of part-throttle ping, so need to think 'cold' coolant or cold air.
There is no use to check the IAT or MAP sensors if it is pinging at part-throttle. A partially clogged fuel injector also is not likely to be the problem if part-throttle pinging is occurring.
If your truck pings worse at part throttle, then that limits what you can do to stop it.
When you hear a racer say: "One of my cylinders got a little too lean and then detonation blew a hole in that piston," what he really means in "Engineer Speak" is: "My mixture was running at the best-power ratio of 13 to 1, then something happened and one of the cylinders' mixture began to drift leaner and leaner until it got close to 14.7 where detonation began. "

In the January 2000 issue of High Performance Mopar, there is an article about what a good machine shop does when they build up a Mopar engine. The article is about Roger's Engine Shop (RES) in Lansing Michigan, which apparently specializes in Mopars. The title of the article is "Bottom End Beef Up." In the article RES is complimentary about the quality of late-model Mopar blocks, and says that mopar connecting rods are first rate, but says this about Mopar crankshafts:
(begin quote) ----------------- "Most OEM crankshafts are out of stroke spec, some by as much as 0.025 to 0.050 ! That means you'll be down on cubes in one or all cylinders. Indexing the crank is a time-honored way of ensuring you engine makes all the cubic inches advertised. Additionally, the as-delivered factory cranks seldom place the rod journals at 90-degree intervals, so timing the ignition and cam is off. " ------------------ (end quote)
Obviously there may be a bit of 'hyping' in these statements in order to draw in crank grinding business to their shop, but it got me to wondering about Mopar crankshafts and the reports on Dirt of pinging in 318/360 engines that sometimes defies easy cure. While the article emphasizes the small loss of cubic inches from a crankshaft having undersized stroke, a crankshaft that had an OVERSIZED stroke on one cylinder of 0.050 inches would have increased compression ratio in that cylinder.
An oversized stroke of 0.050 from 3.58 to 3.63 inches would bump the compression ratio from the 360's spec of 8.9 to about 9.4 So that cylinder would tend to ping earlier than the other seven cylinders. If the rod journal on the crank of that cylinder happened to be at 91 degrees rather than 90, that could cause further ping problems, because even if the sparkplug is fired at the correct time, the piston is one degree short of where it should be. In this condition the cylinder would act like its ignition timing had been advanced a degree.
So maybe "Mystery Ping" on Magnum 5.2/5.9 V8's could be related to sloppy tolerances on crankshafts - which are very very seldom pulled out at a dealership and measured. If the machining on the deck height of the block, and the underside of the head were slightly off-spec on the too-small side, this would make things even worse. The article in High Performance Mopar is worth a browse if you are killing time near a magazine rack.

Solutions

Solution one: Reroute/replace the spark plug wires

• TSB 18-16-98 95-97 V-10
• TSB 18-48-98 94-99 V6, V8

Check/replace the spark plug wires. Even on engines with few miles, many have experienced pinging problems caused by bad spark plug wires. One cylinder (maybe more) would misfire, causing the ECM to detect a rich condition, and lean out the mixture to the other cylinders, causing the engine to ping. Look for open wires, intermittent wires, and leaking wires (look for leaky wires on a dark, damp night).

Wire rerouting: You don't need to buy the overpriced Dodge parts listed, just look at the passenger side of your engine and examine the wire clips that push down in the valve cover bolts. Go to an auto parts store and buy some of these, plus some nylon wire ties and some of that blacksplit plastic tubing (Dodge calls this 'convolute') to cover & protect wire.

Solution two: Replace a leaking intake manifold and plenum gaskets

• TSB 09-05-00 94-99 V6, V8

Chrysler now recommends a more sensitive test to see if the Magnum V8 intake manifold to block gaskets are leaking. If this gasket is leaking, it can cause the engine to ping.
The old test (I think it is described in the TSB's) was to take the PCV valve loose from the passenger side of the engine and oil vapor breather-to-air cleaner hose loose from the driver's side.
With the engine running at idle, use your two thumbs to seal the PCV valve hole on the passenger side and seal the hose going to the valve cover on the driver's side.
Wait a few seconds. If you feel a slight pressure building up due to blowby gases filling the engine block's interior - your engine is normal and your manifold to block gasket is probably ok.
If you feel a slight vacuum - your manifold-to-block gasket may be bad and one or more leaks is allowing the high vacuum in the manifold to suck the gases out of the interior of the block.

Many technicians now feel the above method only finds really bad leaks.

To find the lesser leaks they recommend putting two doses of 4-IN-1 Blacklight dye (Mopar part number 05010042AA /cost $8 per tiny bottle) in the engine oil and driving the truck for 200-300 miles.
They then take off the air cleaner and shine a blacklight down into the throttle body. If they see ultraviolet dye glowing on the bottom floor of the intake manifold - they take the manifold off and re-do the gasket.
I thought about that - it sounded good - but then I remembered that the PCV valve empties into the intake manifold - and the oil vapor breather empties into the air cleaner housing which is almost the same thing. I asked him, "Wouldn't some dye find its way into the manifold through the PCV and the breather even if there was not a leak?" He said, "We haven't found that to be a problem."
I bought two bottles of the blacklight dye - but I may temporarily disconnect my PCV and breather for the 200 mile test anyway - because for out-of-warranty work I would be the one to pay if they misdiagnosed a leak that wasn't there. Hank

Solution three: Replace or Reprogram the PCM

• Numerous TSB's have been issued
• Your Dodge dealer can retard the ignition timing. Disadvantage: you lose hp and mpg this way.

Solution 4: Replace thermostat, antifreeze, and/or radiator cap

A cooler 180 degree thermostat and cooler intake air will reduce the tendency to ping at part-throttle. The 180 not only causes the truck to run cooler (reducing the intake air charge temp), but it also causes the truck to run cooler (this fools the computer, which believes that the truck is not completely warmed up so it runs a richer air\fuel mix).
Some have even used a 170 degree thermostat. Each 5 degrees of thermostat drop is supposed to be about like adding 1 Octane number to that of whatever gasoline you are using. The 170 thermostat may set a fault code for "Engine operating temperature not achieved in specified time" and illuminate the "Check Engine" light. Some have experienced this, others have not set the fault code.
According to Dakota Power Secrets in the January 1999 issue of Mopar Muscle, the Magnum thermostat is rated at 195 degrees F. The engine controller is designed to make maximum power at 182 deg F. Especially with a high performance engine computer, the engine generates high combustion chamber temperatures under heavy throttle conditions and this heat is transferred to the coolant above the chamber. The hot coolant forms air pockets that create combustion chamber hot spots; engine ping is the result. Dropping the thermostat to 185 or 180 degrees will stop most of the coolant pocketing, and the engine fuel economy and power will improve.

Another cheap thing that helps your cooling system to suppress pinging is to change out your 16 lb radiator cap to a 20 lb radiator cap. Mercedes, BMW and Caddilac vehicles use 20lb radiator caps and they will fit the Ram's radiator. Cost about $12.
The 20 psi cap will help suppress a thing called 'nucleate boiling' of the coolant on the hot spots of the cylinder head. This is where the metal is so hot that a steam bubble forms. More pressure makes the bubbles harder to form. Be sure to switch radiator caps when the engine is dead cold - not just for safety - but because the cap needs a cold coolant to fully build up the 20 psi pressure as it gets hot.
Along the same lines you could drain out 5 quarts of the 50/50 ethylene glycol/water coolant that is in your engine and replace it with 5 quarts of pure ethylene glycol. Cost about $8. There are 15 quarts total in the Ram's cooling system, so this substitution with make your system consist of the 5 fresh quarts of new EG, plus 10 old quarts that are a 50/50 mixture (ie 5 quarts EG and 5 quarts water). The new mixture therefore is 10 quarts total EG plus 5 quarts water. This is 66% ethylene glycol and 33% water. This is the greatest mixture of EG that Chrysler recommends - any more and the dissolved corrosion additives will drop out of the mixture and plug radiator tubes. A 66% mixture has good and bad points: it does tend to help eliminate cylinder head hot spots/steam bubbles and hence lessen ping - but it can't quite carry away as much total heat from engine to radiator as either straight water or a 50/50 mixture. You probably won't notice this lessened heat carrying ability unless you tow a trailer up a mountain pass.

Solution 5: Change fuel, add octane booster, use fuel system cleaner

For ping at WOT only, try a higher octane gasoline.
For part throttle ping:

If you run a cylinder compression test and find one or more cylinders that measure higher than 170-180 psi, there is a good chance that it will ping on anything less than high octane gasoline. A build up of carbon deposits on the piston tops (from engine oil leaking through an intake valve stem seal or intake manifold gasket) is the most common cause of high compression readings from one/two cylinders.
For engines with carbon buildup or persistent part throttle ping, run through three Techron treatments. Let your gas tank get down to one quarter full (about 8 gallons to dry) and add a $7 bottle of Chevron Techron. Run this down to empty. Then add 12 gallons more gasoline and add another bottle of Techron. Run this to empty, add 12 more gallons plus a third bottle of Techron. What this will do is clean out carbon deposits out of your combustion chambers and lower your compression ratio back to the factory 8.8 number it had when the cylinder was clean shiny metal. It is a cheap thing to do and I almost guarantee it will lessen the pinging on 93 octane. Carbon deposits not only raise compression - it also insulates the cylinder head and prevents good cooling from above. The Techron may also clean out a partially plugged fuel injector that is causing one cylinder to run leaner than the other seven. This is the same problem as the low fuel pressure but is confined to one cylinder. There is no guarantee that a Techron treatment will completely eliminate the pinging.

Chrysler has a combustion chamber cleaner that the service departments use.

Here is some more info on heavier-duty injector cleaning:
For off-the-engine cleaning, with three manufacturer's systems reviewed: http://www.asashop.org/autoinc/sept98/techtotech.htm
For on-the-engine cleaning: http://www.asashop.org/autoinc/june98/techtotech.htm
{These are very well written, comprehensive articles.}

Get your dealer to check your fuel pressure - on the road - at wide open throttle acceleration at 75 mph in 2nd gear. Hook up the gauge with a short hose extension and tape it to the windshield so you and the service guy can see it. It should be 49.5 psi or better. Any less and your fuel injectors are not putting out what the computer is expecting them to. This will cause your engine at WOT to run lean above 14.7 Air/Fuel when Mopar expects good fuel injector flow to make it slightly richer (say 13.7) to suppress pinging. Pinging is at its absolute worse at about 15 to one.


Solution 6: Change to cooler spark plugs - Stock OEM: Champion RC12YC

Equivalent-to-stock, normal heat range plugs for 5.2/5.9 V8 engines

• Bosch Platinum+4, P/N 4418 (but not intended for truck applications)
• Bosch Platinums (old style, not +4's)
• FR8DPX, P/N 4102 (gap .044)
• AC Delco Rapid Fires, P/N 5 Torque Master, P/N VFN8BR ($12.50 per plug)
• http://www.torquemaster.com Champion Truck Plugs P/N 4071
• NGK FR5-1, P/N 7252
• Autolite Double Platinum

RC12YC - The 12 is the heat range. Higher is hotter with Champions. You can buy a RC10YC or a RC09YC (stock numbers 4434 and 4412). All will be progressively colder than the factory stock RC12YC.
If you need a colder range than the Champion RC9YC, page 23 of the "High Performance Heat Range Chart and Tuning Guide" says that Champion Racing plugs C63YC, C61YC, C59YC and C57YC are available. Here the '63' to '57' are the very cold racing heat ranges. Plugs that are too cold can make the engine a cold-tempered beast - hard to start and warm up in cold temperatures, and prone to fouling.

Stock recommended gap is .035 but many have been measured at .040 to .065.

Bosch 4+ and Splitfire sparkplugs have a reputation for pinging in Magnum engines. Champion Truckplugs or the Bosch regular platinum FR7DPX seem to work best, particularly in the number 7 and 8 cylinders because they seem to run the hottest.
If your counterguys are really clueless and can only find plugs by car model - tell them to give you the : {Sparkplug Manufacturer of Your Choice} plug for the 1995 Dodge Stealth 3.0L V6 Turbo - this car's engine is turbocharged but the cylinder head design is similar to the Magnum V8. It takes one heat range colder than the Ram, otherwise it is the same style/thread sparkplug. NGK recommends the platinum tipped PFR6J-11, stock number 2743 for the Dodge Stealth turbo.
Champion distributes a little booklet with good color photos about reading plugs after test runs called "High Performance Heat Range Chart and Tuning Guide". It is Publication Reorder Number 98770 and Champion will send it to you for free.
Buying 16 plugs, and finding the 8 that stop or "index" correctly at the best angle by chance, is worth the extra time and money. The Magnum 'Squish and Quench' cylinder head design seems to like indexing. To Index: Aim the side of the sparkplug with the open gap toward the center of the engine.

If you are running the KN FIPK with the inlet inside the engine compartment, that might be something to try changing. Engine compartment air is higher temperature - and higher inlet temperatures lead to higher temperatures at every stage of combustion.

Solution 7: Check/replace the EGR valve

Gasoline engines run an aggressive spark advance curve and rely on EGR to prevent engine ping. If the EGR valve has clogged or stuck (or been blocked by those seeking to improve mileage), the quick advance curve will cause the engine to ping. If all else has failed, verify that the EGR circuit is functioning properly.

Solution 8: Water Injection

_________________________________________________

If you don't have copper plugs in there, that's a big problem. Use factory Champions, run seafoam, put in a 180 stat.