Am I the only one having spark knock issues?

[DanW]

What's oil certifications got to do with pinging from detonation?

Read up on low speed pre-ignition, known as LSPI and DI engines, particularly DI/Turbo engines. Dexos 1 G2, SN+ and SP/GF6 were developed to combat and eliminate it. It is mainly caused by fuel or oil droplets, but in older non-DI engines, carbon typically causes it. I just have a hunch that these newer oil formulations help even when carbon is the cause. Detonation is another term that can describe a similar condition that results in pinging, but as was said before, usually happens after the first explosion. In non-DI engines, it is most likely caused by carbon that gets hot or even burns, causing the fuel/air mixture to ignite early, or late, as the case may be. But there could be other causes, too.

My 3.8, like many, is an oil burner. I'm a firm believer that the oil is going through the PCV and burning in the cylinders where most of it vents. They have more carbon/varnish than the other 4 cylinders. You can see it on the top of the pistons right through the spark plug holes. It has not been as bad since I've run SN, SN+ oils or since Shell reformulated their additives. I've had zero pinging since then, so it is either one, the other, or a combo of both. Nothing else has changed, so that's the hypothesis. The engine still uses about the same amount of oil as ever, so that hasn't really changed, either. If it were burning less oil, I'd suspect that to be why it doesn't ping anymore.

Here's a good article that gives a good and simple explanation of LSPI... LSPI

Again, I'm only doing an educated guess as to these oils' ability to affect pinging on non-DI engines such as the Jeep/Chrysler 3.8.

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[DanW]

Whoa - pre-ignition is ignition BEFORE the spark.
Detonation is a second flame front that happens AFTER the spark.
Octane resists self-ignition - PERIOD.
Detonation is caused when the normal progressing flame front forces unburned mix "into a corner" and raises the pressure and thus temperature to the point it self-ignites. Then you have a second flame front advancing and the ping is the sonic boom caused by the collision.

Higher octane fuel has longer chains that resist self-ignition.

PRE-IGNITION is a TOTALLY different animal and is caused by HOT SPOTS - such as the wrong heat range spark plug, carbon build-up, sharp edges on valves after a crappy valve job and so on.

Let's not get the two - detonation and pre-ignition - mixed up or intertwined. They are two distinct things.

Also - spark plugs have ZERO to do with detonation. That's because detonation is a problem with a SECOND flame front, AFTER the plug fires. Octane and/or timing deal with that.

Spark plugs CAN cause preignition if they run too hot. Most of the issues with spark plugs isn't the quality of the plug, it's how hot it runs, how it cools, length and so on.

The spark plugs in that 3.8 DO make a difference, though, so the ping in that engine's case is likely pre-ignition. I think you are spot-on about the quality of the plug not being the issue. The NGK's I ran were at the time the highest rated plug on the market. The Champions were considered good, but not high end. But that engine performs better with them. If I swapped those NGKs in there right now, within one or two tanks of gas the pinging would get so bad it would drive you nuts and even give concern for engine damage. It was THAT bad. They were properly gapped, too.

IIRC, detonation is more commonly experienced as run-on. I haven't seen that since my Dad's last carburated engine. I'm not sure I've experienced it in a more modern fuel injected engine. I've only experienced pre-ignition pinging. And I've only experienced that in 3 engines. A Chevy 4.3, Jeep 2.5, and Jeep 3.8. The Jeep 3.8 having the worst case of it.

Again, I'm just guessing as to why there is no pinging at all, in any amount of miles, on my 3.8. But the only variables that changed were the fuel additive package and moving on from API SN oils. So it was one, the other, or both. That engine didn't heal itself, LOL!

 

[ShadowsPapa]

Read up on low speed pre-ignition, known as LSPI and DI engines, particularly DI/Turbo engines. Dexos 1 G2, SN+ and SP/GF6 were developed to combat and eliminate it. It is mainly caused by fuel or oil droplets, but in older non-DI engines, carbon typically causes it. I just have a hunch that these newer oil formulations help even when carbon is the cause. Detonation is another term that can describe a similar condition that results in pinging, but as was said before, usually happens after the first explosion. In non-DI engines, it is most likely caused by carbon that gets hot or even burns, causing the fuel/air mixture to ignite early, or late, as the case may be. But there could be other causes, too.

My 3.8, like many, is an oil burner. I'm a firm believer that the oil is going through the PCV and burning in the cylinders where most of it vents. They have more carbon/varnish than the other 4 cylinders. You can see it on the top of the pistons right through the spark plug holes. It has not been as bad since I've run SN, SN+ oils or since Shell reformulated their additives. I've had zero pinging since then, so it is either one, the other, or a combo of both. Nothing else has changed, so that's the hypothesis. The engine still uses about the same amount of oil as ever, so that hasn't really changed, either. If it were burning less oil, I'd suspect that to be why it doesn't ping anymore.

Here's a good article that gives a good and simple explanation of LSPI... LSPI

Again, I'm only doing an educated guess as to these oils' ability to affect pinging on non-DI engines such as the Jeep/Chrysler 3.8.

Oil in the mixture can cause detonation. This is why some engines that didn't detonate in early years suddenly start to as they also start to "consume oil"
Burning oil causes carbon which can get hot and cause pre-ignition.
But a secondary problem is the carbon raising compression as it takes up space.

But a new engine? Shouldn't be oil getting into the cylinders.
My 4.0 uses zero oil between changes, the spark plugs after 35,000 miles look clean and new - except for the fact they need changing due to wear.
Odd to imagine a brand new 3.6 would have more issues than other engines.

I've never experienced any ping in my 3.6 engines - ever - at over 10,000 miles.

 

[ShadowsPapa]

The spark plugs in that 3.8 DO make a difference, though, so the ping in that engine's case is likely pre-ignition. I think you are spot-on about the quality of the plug not being the issue. The NGK's I ran were at the time the highest rated plug on the market. The Champions were considered good, but not high end. But that engine performs better with them. If I swapped those NGKs in there right now, within one or two tanks of gas the pinging would get so bad it would drive you nuts and even give concern for engine damage. It was THAT bad. They were properly gapped, too.

IIRC, detonation is more commonly experienced as run-on. I haven't seen that since my Dad's last carburated engine. I'm not sure I've experienced it in a more modern fuel injected engine. I've only experienced pre-ignition pinging. And I've only experienced that in 3 engines. A Chevy 4.3, Jeep 2.5, and Jeep 3.8. The Jeep 3.8 having the worst case of it.

Again, I'm just guessing as to why there is no pinging at all, in any amount of miles, on my 3.8. But the only variables that changed were the fuel additive package and moving on from API SN oils. So it was one, the other, or both. That engine didn't heal itself, LOL!

Funny thing - I always have the best luck with the plugs my vehicles came with. Shouldn't be - but there are so many physical differences and heat ranges almost never translate exactly across brands.
I run Champions in my vehicles (AMC and Chrysler products) and have never had a spark plug issue. The only time I had any issues I tried NGK - no joy, and Autolite (worked fine) but I always went back to the originals, Champions.
I'll never say what plug is best - only what's best for a given situation or engine/vehicle in my personal experiences.

 

[Logan94605]

So much to take in! For now I'm going to try a better quality fuel than than the Safeway brand.....
It's so hard to resit that 70 cent a gallon discount after a trip to the grocery store ;-)

 

[DanW]

So much to take in! For now I'm going to try a better quality fuel than than the Safeway brand.....
It's so hard to resit that 70 cent a gallon discount after a trip to the grocery store ;-)

Here is a list of Top Tier brands. https://toptiergas.com/licensed-brands/

The biggest names, Shell, Chevron, Exxon, and BP are all Top Tier and usually exceed even Top Tier standards. There are a few big names, like Speedway, that are not Top Tier, so I'd go by the list.

You will sometimes hear someone, especially tanker drivers, who will say, "They all come from the same refinery or distribution center, out of the same storage tank or pipeline." That is often true, but that's not what separates the fuels. It is the additive package, which is selectable by the brand. Shell, Chevron, Exxon, BP, etc, all have their own proprietary additive packages. Others use different levels of packages that the refinery offers, which are fine, too, if they meet Top Tier standards. The additive package make ALL the difference in the quality of the fuels, even if the base fuel is the same.

 

[Jeeperjamie]

So much to take in! For now I'm going to try a better quality fuel than than the Safeway brand.....
It's so hard to resit that 70 cent a gallon discount after a trip to the grocery store ;-)

Use this app if you want to get money back. I use it and have made almost $140 in the past year doing it. You can cash it out to a visa gift card or Amazon credit. BP and Shell are two of the main participants. Easy as checking in and they give you money back on every gallon you get. It's legit

https://app.getupside.com/

It's better to me than saving the 70 cents because you can spend the money on whatever you want. I spent my last cash out on the lights and mounts for my Jeep on the windshield A Pillar, they only ended up costing me $5.

 

[ShadowsPapa]

Here is a list of Top Tier brands. https://toptiergas.com/licensed-brands/

The biggest names, Shell, Chevron, Exxon, and BP are all Top Tier and usually exceed even Top Tier standards. There are a few big names, like Speedway, that are not Top Tier, so I'd go by the list.

You will sometimes hear someone, especially tanker drivers, who will say, "They all come from the same refinery or distribution center, out of the same storage tank or pipeline." That is often true, but that's not what separates the fuels. It is the additive package, which is selectable by the brand. Shell, Chevron, Exxon, BP, etc, all have their own proprietary additive packages. Others use different levels of packages that the refinery offers, which are fine, too, if they meet Top Tier standards. The additive package make ALL the difference in the quality of the fuels, even if the base fuel is the same.

We live about 7 miles from a huge pipeline system and large distribution system - constantly see tankers pulling in and out for multiple "gasoline companies" whenever we drive by the terminal.

Anyway, I wonder how the gas we buy rates. We buy almost exclusively from Casey's whenever we can, anywhere in Iowa or other states they are in.
Otherwise, honestly, we buy where-ever it's a decent price and the place looks maintained and clean.
I've never had a problem with gasoline.
We aren't out of Iowa a lot, but when I've driven to other states - Ohio, Indiana, MN, WI, MO, whatever, never had what I'd call a problem tank of gas. Not had water problems or dirty injectors. The injectors in my 94 4.0 went over 130,000 miles and I replaced them "just because" - might put them back as I think they were smoother than the new ones!
The injectors in my 2004 4.0 have 127,000 miles on them - zero starting or running issues.
So either I'm lucky - or I happen to choose the right stations LOL

But we've bought gas from Casey's General Stores for YEARS, once in a while at Hy Vee as we get points for buying groceries, sometimes we save big on gas (Casey's honors the Hy Vee fuel saver points) I have a 20 cent off gas coupon in my wallet now because I got a flu shot at Hy Vee.

So where does the gas come from for Casey's or Hy Vee ?

 

[DanW]

We live about 7 miles from a huge pipeline system and large distribution system - constantly see tankers pulling in and out for multiple "gasoline companies" whenever we drive by the terminal.

Anyway, I wonder how the gas we buy rates. We buy almost exclusively from Casey's whenever we can, anywhere in Iowa or other states they are in.
Otherwise, honestly, we buy where-ever it's a decent price and the place looks maintained and clean.
I've never had a problem with gasoline.
We aren't out of Iowa a lot, but when I've driven to other states - Ohio, Indiana, MN, WI, MO, whatever, never had what I'd call a problem tank of gas. Not had water problems or dirty injectors. The injectors in my 94 4.0 went over 130,000 miles and I replaced them "just because" - might put them back as I think they were smoother than the new ones!
The injectors in my 2004 4.0 have 127,000 miles on them - zero starting or running issues.
So either I'm lucky - or I happen to choose the right stations LOL

But we've bought gas from Casey's General Stores for YEARS, once in a while at Hy Vee as we get points for buying groceries, sometimes we save big on gas (Casey's honors the Hy Vee fuel saver points) I have a 20 cent off gas coupon in my wallet now because I got a flu shot at Hy Vee.

So where does the gas come from for Casey's or Hy Vee ?

Odds are that they get their fuel from the same source as everyone else in your area, but again, it is the additive package that makes the difference, not the base fuel.

If your engine has no problems, then the minimum standard gas is fine. Most engines do fine with it. But if you get pinging, hesitation, rough idle, or other issues, I'd move to Top Tier.

If you don't see them on the Top Tier list, then they are likely using an EPA minimum standard additive pack, which is better than it used to be and better than gas in most countries. I don't think my 3.6 Pentastar would have trouble with it, but my 3.8 most certainly would. We had a Chevy 350 in a Caprice that would react so badly that I could tell you each tank if you had high quality or cheaper fuel in it.

It is also possible that Caseys or Hy Vee may get an optional additive pack that is better than the minimum. YOu might ask them or check their web sites. Sometimes independent owners do different things, too, so you might see one Casey's with a higher detergent pack than another down the street. You won't see that with the big names, though. They require their additive packages or the franchise would be taken away. They maintain tight quality control.

 

[ShadowsPapa]

Odds are that they get their fuel from the same source as everyone else in your area, but again, it is the additive package that makes the difference, not the base fuel.

If your engine has no problems, then the minimum standard gas is fine. Most engines do fine with it. But if you get pinging, hesitation, rough idle, or other issues, I'd move to Top Tier.

If you don't see them on the Top Tier list, then they are likely using an EPA minimum standard additive pack, which is better than it used to be and better than gas in most countries. I don't think my 3.6 Pentastar would have trouble with it, but my 3.8 most certainly would. We had a Chevy 350 in a Caprice that would react so badly that I could tell you each tank if you had high quality or cheaper fuel in it.

It is also possible that Caseys or Hy Vee may get an optional additive pack that is better than the minimum. YOu might ask them or check their web sites. Sometimes independent owners do different things, too, so you might see one Casey's with a higher detergent pack than another down the street. You won't see that with the big names, though. They require their additive packages or the franchise would be taken away. They maintain tight quality control.

I bet if he's still in charge, Don Lamberti wouldn't allow any big differences. He built that thing up from a single mom and pop shop years ago. They are one of those places with some pride.

Don't see any details here, really - https://www.caseys.com/about-us/quality-fuels

My 70 Javelin did its very best on Walmart premium. I could feel the difference, and less detonation. (replacing the radiator helped that, too)

 

[Gladman]

I have an issue with my 3.6 in the GC.
At cold start-ups only, it runs rough and seems to be a miss in the spark, but I don’t think it is actually a miss.
The condition is enough that I notice it through the seat - a lot of bumps/vibration. I checked the exhaust pipe and it is tight. I also filled several consecutive tanks with premium and there was no difference.
Gave it to the dealer for a cold start and they said they did not experience it, which is BS because I have started it cold 300 times now and it is always the same.
Anyone have a similar experience with this engine?

 

[ShadowsPapa]

I have an issue with my 3.6 in the GC.
At cold start-ups only, it runs rough and seems to be a miss in the spark, but I don’t think it is actually a miss.
The condition is enough that I notice it through the seat - a lot of bumps/vibration. I checked the exhaust pipe and it is tight. I also filled several consecutive tanks with premium and there was no difference.
Gave it to the dealer for a cold start and they said they did not experience it, which is BS because I have started it cold 300 times now and it is always the same.
Anyone have a similar experience with this engine?

We just traded a 2018 Grand Cherokee for a 2021 - no problem with either. SMOOTH as silk. That's how I'd have to describe the 3.6 we've had in the last three GCs we've owned. We had a 2015, 2018 and now a 2021 - perfect running engines, very smooth.
I'd describe the 3.6 in my 2020 JT the same way - very smooth, not even a quiver.

 

[Logan94605]

Use this app if you want to get money back. I use it and have made almost $140 in the past year doing it. You can cash it out to a visa gift card or Amazon credit. BP and Shell are two of the main participants. Easy as checking in and they give you money back on every gallon you get. It's legit

https://app.getupside.com/

It's better to me than saving the 70 cents because you can spend the money on whatever you want. I spent my last cash out on the lights and mounts for my Jeep on the windshield A Pillar, they only ended up costing me $5.

Haha! Here I am driving in circles trying to burn off this tank of discount gas so I can see if it's just a case of bad gas. If you're not familiar, Safeway is a grocery chain in Northern California but it's parent company is multi state so it's like buying gas from Costco or Wallmart. Who knows whats in it... The stations are clean and I never had trouble with the premium in my Audi.

The app looks interesting...I have to download it and see if it works here. Thanks!

 

[ShadowsPapa]

Safeway used to be big here in Iowa, but Hy Vee pretty much ran them out. They were supposedly a family type organization, employee owned and all that but acted more like Microsoft and became "engulf and devour" running other stores out like Walmart used to do.

 

[Logan94605]

Safeway used to be big here in Iowa, but Hy Vee pretty much ran them out. They were supposedly a family type organization, employee owned and all that but acted more like Microsoft and became "engulf and devour" running other stores out like Walmart used to do.

Yup thats them.... haha. Where I live it's good for the basics but a trip to the local produce store and meat market are always included. My sister in-law used to work for the company in Nevada and never had anything good to say.

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