Knock on JB4 Map 2 with 93 Octane (stock Stinger)

[Mr. Tech]

Hi guys, I'm getting what looks/sounds like knock when running Map 2 (logs and snapshot attached). I have a late 2018 Stinger GT2, AWD with brand new (less than 200 miles) Denso plugs from the JB4 site, gapped between .022 and .023. Other than the Denso plugs and the JB4, the car is 100% stock. Also, I'm on 93 octane from a local Shell station which came recommended from a fellow tuner (500WHP BMW)

Here's some other important info. Map 1 runs excellent with a very noticeable power increase, near perfect timing curves, and steady boost through the whole RPM range from 1st gear all the way through 3rd. The JB4 was only installed yesterday so I only have about an hour of drive time on Map 1. I tried Map 2 today since the Map 1 logs were good (confirmed through email with Burger Motorsports).

Just after going WOT (wide open throttle), I hear what sounds like rocks being shaken in a can for about a half second, then nothing except the engine revving until it shifts from 1st to 2nd, then I hear the rocks in a can sound again for another half second right when 2nd gear engages, then no more rocks until shifting into 3rd. Basically, I only hear that sound for the first half second or so of each gear shift at WOT. I don't hear the sound at all during normal driving.

I took a look at the logs and my throttle dips, even though I have the pedal to the floor. At the same time, my timing and boost make consecutive drops all the way through the RPM curve until I shift into 2nd. After that, the logs look pretty normal. From everything I've read, those consecutive drops are to stop knock that's been detected.

Anyone else run into this issue with a stock Stinger on 93 octane? I'm emailing back and for with Burger Motorsports about it, but I figured I'd open this up to the community too.

I expected to run into some issues, but definitely not knock on day 2.

 

[Mr. Tech]

Here's another log showing the issue. Same day, only a few minutes apart from the last log.

 

[sym]

How did you gap your plugs? Did you do the plugs at the same time you added the JB4? Do you get the same noise when you run Map 0?

 

[Mr. Tech]

How did you gap your plugs? Did you do the plugs at the same time you added the JB4? Do you get the same noise when you run Map 0?

Great questions. I gapped the plugs using the same style gapper that BMS sells and a feeler gauge. I did the plugs two days ago and ran those for a whole day (~60 miles). I logged a couple 0-60 pulls on the new Densos and everything looked perfect (logged using a BT OBD2 adapter and the Torque Pro app with a plug-in).

I didn't install the JB4 until the following night. At which time, Map 1 ran great. Map 1 also ran great this morning for a total of around 40-50 miles on Map 1.

Oh, and I don't get the noise on either Map 0 or Map 1.

 

[sym]

It sounds like either an octane or a spark plug issue. If you have access to E85, add 4 or 5 gallons to your tank. If you're still getting that noise on the E85 blend I'd check your spark plugs out.

I'm surprised though. I've been filling up at Shell (the marketing for the 93 Nitro+ totally got me). It has a 99 RON vs the 98 RON in 93 octane pump gas.

 

[Mr. Tech]

It sounds like either an octane or a spark plug issue. If you have access to E85, add 4 or 5 gallons to your tank. If you're still getting that noise on the E85 blend I'd check your spark plugs out.

I'm surprised though. I've been filling up at Shell (the marketing for the 93 Nitro+ totally got me). It has a 99 RON vs the 98 RON in 93 octane pump gas.

Unfortunately I don't have access to any higher octane. But with other Stinger owners running Map 2 on 91 octane, I find it hard to believe that the gas is THAT bad from Shell.

Do you know which plug is linked to ign 1? That trim moves around the most. I could check that one first. That said, I triple checked all the gaps just two days ago on brand new plugs purchased direct from BMS.

 

[JDM_Man]

Unfortunately I don't have access to any higher octane. But with other Stinger owners running Map 2 on 91 octane, I find it hard to believe that the gas is THAT bad from Shell.

Do you know which plug is linked to ign 1? That trim moves around the most. I could check that one first. That said, I triple checked all the gaps just two days ago on brand new plugs purchased direct from BMS.

Could be a bad tank of gas (this happens) or do you have any old gas in your tank? Like you said you have less then 200 miles on your car and I am guessing some of the gas the stealership put in there is still there (probably the cheapest 87 available).

Run the full tank out and refill again and see what happens, like I said probably old 87 in the tank from the stealership.

 

[Terry@BMS]

No significant knock seen in the logs. Just a timing drop in one cylinder. What you're hearing could be adaption related or just a sign of subpar fuel. If map1 is running best for you stick with that and evaluate down the road when you're able to change the fuel and/or connect the fuel wires.

 

[Mr. Tech]

Could be a bad tank of gas (this happens) or do you have any old gas in your tank? Like you said you have less then 200 miles on your car and I am guessing some of the gas the stealership put in there is still there (probably the cheapest 87 available).

Run the full tank out and refill again and see what happens, like I said probably old 87 in the tank from the stealership.

Thanks for the feedback. I should have clarified that it's just the spark plugs that have 200 miles on them. The car has just over 10k on it and I've been using 93 octane since day one.

 

[JDM_Man]

Thanks for the feedback. I should have clarified that it's just the spark plugs that have 200 miles on them. The car has just over 10k on it and I've been using 93 octane since day one.

Did you connect the fuel wires?

 

[ecko04]

Gotta connect those fuel wires otherwise you could be running rich on Map 2.

 

[washguy]

Add the fuel wires and put 4 gals of E85 in a full tank of 93 ....Wash

 

[TwistedOrca]

Add the fuel wires and put 4 gals of E85 in a full tank of 93 ....Wash

Have yet to try this....

 

[washguy]

Twisted Terry likes this combo...so will your car....try it you will like it ! Wash

 

[Mr. Tech]

Alright, a few updates. After emailing back and forth with Terry, he told me to turn off the fuel wire option since it wasn't connected (I didn't know it came turned on by default). However, it sounded like that would only affect the logs, not the performance. Either way, I updated the setting.

I also checked my JB4 box and noticed that I didn't tie it down tight enough so it would slide and make a "ting" sound every time I accelerated hard. Ironically, it sounded exactly like knock/detonation that I heard in a few YouTube videos. So looks like part of the issue is that I'm an idiot haha.

Since securing my JB4 better, part of the concerning sound is gone, but I still hear a... "Ch-kuhhh" sound about a second after going wide open throttle, just before the power kicks in. This is a sound I don't recall hearing in Map 0 or Map 1, but I'll need to test it out again when I get back from a family vacation. At first I thought it could be the throttle slamming open, but I should hear that regardless of the map.

I've attached a few more logs. Surprisingly, the issue with boost, timing and throttle getting cut is absent from both logs. The only throttle cut I see is right after a shift, which I understand to be normal-ish (my stock Stinger never did this in any of the dozen plus logs I took before installing the JB4). That said, the throttle drop only happened in one of the logs. I should also point out that the ambient temperature was 20 degrees cooler (Fahrenheit).

So the new question is, what could make a "ch-kuhhh" sound that could only be heard when running Map 2? It's pretty faint, but I can try to get a video of the sound and post it later.

And the second question, how do these new logs look?

Actually, here's a third question too. What could cause the throttle to occasionally drop right after a shift? I've heard that it's "normal" but I'd like to know why.

 

[Mr. Tech]

Add the fuel wires and put 4 gals of E85 in a full tank of 93 ....Wash

Unfortunately, I don't have access to E85 where I live. Thanks for the suggestion though!

 

[Mr. Tech]

Did you connect the fuel wires?

Not yet, waiting for the plug and play solution.

 

[Mr. Tech]

Gotta connect those fuel wires otherwise you could be running rich on Map 2.

Yeah, the logs do look pretty rich. Terry said he'd have plug and play fuel wire kits ready in the next few weeks so I'm holding out for that.

 

[Terry@BMS]

Throttle is used to regulate boost, boost tapers at redline, so you should see throttle movement during shifts especially on lower maps. Look at psi vs psi2 to see how much trimming is taking place (not throttle position that won't tell you).

 

[Jeaddi]

Alright, a few updates. After emailing back and forth with Terry, he told me to turn off the fuel wire option since it wasn't connected (I didn't know it came turned on by default). However, it sounded like that would only affect the logs, not the performance. Either way, I updated the setting.

I also checked my JB4 box and noticed that I didn't tie it down tight enough so it would slide and make a "ting" sound every time I accelerated hard. Ironically, it sounded exactly like knock/detonation that I heard in a few YouTube videos. So looks like part of the issue is that I'm an idiot haha.

Since securing my JB4 better, part of the concerning sound is gone, but I still hear a... "Ch-kuhhh" sound about a second after going wide open throttle, just before the power kicks in. This is a sound I don't recall hearing in Map 0 or Map 1, but I'll need to test it out again when I get back from a family vacation. At first I thought it could be the throttle slamming open, but I should hear that regardless of the map.

I've attached a few more logs. Surprisingly, the issue with boost, timing and throttle getting cut is absent from both logs. The only throttle cut I see is right after a shift, which I understand to be normal-ish (my stock Stinger never did this in any of the dozen plus logs I took before installing the JB4). That said, the throttle drop only happened in one of the logs. I should also point out that the ambient temperature was 20 degrees cooler (Fahrenheit).

So the new question is, what could make a "ch-kuhhh" sound that could only be heard when running Map 2? It's pretty faint, but I can try to get a video of the sound and post it later.

And the second question, how do these new logs look?

Actually, here's a third question too. What could cause the throttle to occasionally drop right after a shift? I've heard that it's "normal" but I'd like to know why.

How do you turn off the fuel wire option? I have the latest firmware, but don’t have my fuel wires connected.