Minor Ping/Piston Slap on Acceleration when Warm?

[rpr]

I see numerous posts on noise issues when accelerating and the engine is warm, but they usually end up veering into a different direction where there’s a vibratory rattle from a heat shield or something that’s at fault. My issue seems to definitely be ping and/or very minor piston slap, it does not sound like a vibratory rattle from two components contacting each other.

What’s confounding though is that it’s always been present from day 1 and it does not throw any error codes. Oil looks good. Sounds like a subtle but classic timing related ping.

With no ability to modify the timing on these trucks, has anyone found faulty knock sensors or something like that on their trucks?

 

[hemihustlin]

well ram does reccomend 89 octane so if youre not already running that or better this would be a logical first step in finding pre detonation problems

 

[ramffml]

I see numerous posts on noise issues when accelerating and the engine is warm, but they usually end up veering into a different direction where there’s a vibratory rattle from a heat shield or something that’s at fault. My issue seems to definitely be ping and/or very minor piston slap, it does not sound like a vibratory rattle from two components contacting each other.

What’s confounding though is that it’s always been present from day 1 and it does not throw any error codes. Oil looks good. Sounds like a subtle but classic timing related ping.

With no ability to modify the timing on these trucks, has anyone found faulty knock sensors or something like that on their trucks?

You won't get piston slap when the engine is warm/hot, because at that point the different materials in the engine (aluminum, iron etc) are within spec and the distance between cylinder wall and piston are no longer large enough for there to be room for that slap.

But yes my truck pings (detonation) when its hot. Worse on 87 octane. I haven't yet found a solution, but my goal is to lower engine temps by installing a 180 thermostat and adjusting the fan to turn on quicker. I already did the AGS delete which helped a small bit.

I'm thinking a catch can might help too but that's just a guess.

The manual does note that some amount of pinging is normal, but I'd be happy to get rid of it all.

 

[rpr]

Thanks for the reminder on that, I had actually forgotten that they list 87 octane as “acceptable” but “recommend” 89.

I used to use 93 for a while before I got tired of spending an extra $1/gallon and I think it did the same thing, but it’s worth a try to verify.

I wouldn’t think an “acceptable” octane should cause a ping or piston slap though if everything was operating as designed.

IMHO, ping and piston slap are not “acceptable”.

 

[rpr]

Ramffml: Good info, I wasn’t aware the manual said some pinging was normal. Not normal in my world.

For what it’s worth I have a catch can so I don’t think that will help you.

Also, I have a custom grill that increases airflow to the radiator. Even though in theory once it gets up to operating temp a different grill shouldn’t make a difference, if the temp gauge can be trusted it doesn’t get up to the same temp that it used to with the OEM grill. So I’m not sure if a lower temp thermostat will help either. Let us know either way if you can.

Thanks.

 

[Wild one]

Ramffml: Good info, I wasn’t aware the manual said some pinging was normal. Not normal in my world.

For what it’s worth I have a catch can do I don’t think that will help you.

Also, I have a custom grill that increases airflow to the radiator. Even though in theory once it gets up to operating temp a different grill shouldn’t make a difference, if the temp gauge can be trusted it doesn’t get up to the same temp that it used to with the OEM grill. So I’m not sure if a lower temp thermostat will help either. Let us know either way if you can.

Thanks.

First step up in Dodges Direct Connection Stage packages is a 180 thermostat.If Ma Mopar is putting a 180 t-stat in with their hi-po upgrade kits that still keep full warrenty if installed by an accredited dealer ,there has to be a benefit i'd think. I run 180 thermostats in all 3 of my FCA products,and beat the living hell out of 2 of them,and have never had coolant temps exceed 200,even on nitrous neither of my 2 toys exceed 200F

 

[BackCountryAK]

My truck also has a ping when warm outside. Pretty much started after the second year of ownership. Truck has had a catch can since new and I changed to a 180 degree thermostat along with a tune to adjust the efan to come on sooner after I noticed the pinging under light load. No change at all even when running our 90 premium in AK lol. The only time it has not pinged in the summer is when I ran 5 gallons of VP C10!

I thought I'd try something different this year before I changed out the winter oil as I've wondered if the pinging could be caused by carbon deposits attributed by wintertime idling and short trips to my job. I ran three consecutive applications of Red Line SI-1 and was hoping for a miracle but the ping is still there and the piston tops are still dirty. I replaced the spark plugs this go around, along with a new PCV valve and made sure the intake manifold bolts were still snug. It's only 46 degrees today so not warm enough to see if anything made a difference (I don't have high hopes). Thanks to Wild One for the gear wrench advise for the plugs (it still sucks but way better than previous times)!

 

[rpr]

I tried 89 octane with last fill up. Made no difference.

 

[rpr]

Backcountry, how many miles on those plugs?

 

[BackCountryAK]

Backcountry, how many miles on those plugs?

Just shy of 46k.

 

[Treburkulosis]

Dodge may recommend it, but mine has only seen a handful of 89 fill ups in the last 7 years. I run 87 and mine is coming up on 160k. No issues ever. I just make sure and get a reputable gas station Shell or Chevron or Texaco.

 

[ramffml]

My truck also has a ping when warm outside. Pretty much started after the second year of ownership. Truck has had a catch can since new and I changed to a 180 degree thermostat along with a tune to adjust the efan to come on sooner after I noticed the pinging under light load. No change at all even when running our 90 premium in AK lol. The only time it has not pinged in the summer is when I ran 5 gallons of VP C10!

I thought I'd try something different this year before I changed out the winter oil as I've wondered if the pinging could be caused by carbon deposits attributed by wintertime idling and short trips to my job. I ran three consecutive applications of Red Line SI-1 and was hoping for a miracle but the ping is still there and the piston tops are still dirty. I replaced the spark plugs this go around, along with a new PCV valve and made sure the intake manifold bolts were still snug. It's only 46 degrees today so not warm enough to see if anything made a difference (I don't have high hopes). Thanks to Wild One for the gear wrench advise for the plugs (it still sucks but way better than previous times)!

What oil are you running, brand and viscosity?

Have you tried switching to an oil that mitigates LSPI (these oils usually use more amounts of magnesium and less of calcium)? I did try this over the winter and I'm almost certain I had less pinging over the winter, but temperatures have also climbed here recently and I know it definitely pings more when it reaches operating temp so it might just be the cold temps that helped vs the LSPI oil.

 

[Treburkulosis]

What oil are you running, brand and viscosity?

Have you tried switching to an oil that mitigates LSPI (these oils usually use more amounts of magnesium and less of calcium)? I did try this over the winter and I'm almost certain I had less pinging over the winter, but temperatures have also climbed here recently and I know it definitely pings more when it reaches operating temp so it might just be the cold temps that helped vs the LSPI oil.

I tend to agree here. Oil and filter plays a huge role in that.

 

[BackCountryAK]

What oil are you running, brand and viscosity?

Have you tried switching to an oil that mitigates LSPI (these oils usually use more amounts of magnesium and less of calcium)? I did try this over the winter and I'm almost certain I had less pinging over the winter, but temperatures have also climbed here recently and I know it definitely pings more when it reaches operating temp so it might just be the cold temps that helped vs the LSPI oil.

Red Line and RP filter - the standard for Ramforum lol. I bounce between 5W20 and 5W30 depending on what's cheaper and can ship through Amazon prime to AK. I'll have to look into LSPI oils for a future change.