[Gregdetroit]

Hey all!
So I was driving my new challenger scat pack today and noticed after about an hour of driving i am noticing the car vibrate while at a complete stop. It happens when idiling (drive park...etc) however it’s not every time. The vibration also only last about 15 seconds or so then it goes away. Once I give it gas all is returned to normal no vibration. Also to be clear the vibration is a very low vibration I can feel it in my seat however it does not shake the vehicle at all. I have almost 600 miles on it and so far no issues. I’m giving it more throttle now that it’s over 500 miles but any ideas?

I also wanted to add it’s almost 100 degrees out today and I’ve noticed my oil temp change ever so slightly randomly.

 

[DeWFPo]

The next time you feel it, turn the A/C off and see if it subsides.

 

[Gregdetroit]

The next time you feel it, turn the A/C off and see if it subsides.

I’ll have to try that next time. If it stops the vibrations would you happen to know what the issue would be? Or is this expected? I previously had an Rt challenger and never had an issue like this before but from other posts I’ve seen this may occur every once in a while.
Appreciate the reply!

 

[19johned53]

Could possibly be your gas, especially at 100°F temps.

If you turn the ac off as De suggested and there's no change, I would definitely try a few different brands of gas.

I've had a rougher idle with some brands than others, both 91 octane.

Just make sure you run your tank down (not out) to get as much of the different brand in.

Worth a shot and best of luck.

 

[Gregdetroit]

Could possibly be your gas, especially at 100°F temps.

If you turn the ac off as De suggested and there's no change, I would definitely try a few different brands of gas.

I've had a rougher idle with some brands than others, both 91 octane.

Just make sure you run your tank down (not out) to get as much of the different brand in.

Worth a shot and best of luck.

Ah ok yeah I will give that a try. That actually makes sense as half the tank is from circle k and the other half is from frys both 91 octane obviously. I really appreciate the response!

 

[19johned53]

Ah ok yeah I will give that a try. That actually makes sense as half the tank is from circle k and the other half is from frys both 91 octane obviously. I really appreciate the response!

I'm in a rural area, so there are more small chain stations than the Big names, but I've tried several when the idle acts up.

Fortunately I have Pure Gas 91 available, and that's what I've been using for years.

Smoother idle, better driveability IMO, and 1.5 to 2 mpg better than the Ethanol blend.

Years back I did some data logging on my previous R/T, and it showed less knock with the Pure 91. Had a Hemi Fever custom 91 tune when I was testing and it just ran at its best with the Pure Gas.

When I bought my SP, I just kept using the same station. I figured why not, and the 392 runs well.

Good luck

 

[Hellraisin]

Ah ok yeah I will give that a try. That actually makes sense as half the tank is from circle k and the other half is from frys both 91 octane obviously. I really appreciate the response!

I've had really spotty results over the years with any fuel that isn't one of the premium brands like Shell/Mobil/BP. Small chains and one-off stations often buy their gas wherever it's cheapest that day, and it can result in weird mixtures in their tanks. Even some of the bigger brands can have problem stations.

When I was turning wrenches professionally we had a Speedway station a couple miles away that sold so much bad gas it was our first question when a customer came in and said their car started running rough all of a sudden with no CEL. If you're buying multiple brands, running down close to empty before a fill up isn't a bad idea if you can.

 

[Rockster]

My Scat Pack is not the smoothest idling engine nor the most stable idling engine ever. Nothing severe enough that I think warrants taking the car in it appears to be just a characteristic of the engine.

What you might be experiencing is the onset of extra parasitic load -- arising from the alternator -- from the radiator fan switching from low speed to high speed or if the A/C is on the radiator fan switching from low speed to high speed.

If the A/C is on the A/C compressor could account for the vibration as it is adjusted to produce more compression of the refrigerant to increase cabin cooling.

Certainly as others have suggested you can try different gasoline. Be sure to buy the proper octane grade and buy from a busy station to ensure you get the freshest gasoline.

The oil temperature is not stable. It will go up if you drive the car in town, that is with stops with the engine idling of course followed by acceleration up to the limit -- even if it is just 35mph -- followed shortly by another stop and more idling. Under these conditions the oil temperature -- this my Scat Pack -- can climb to 230F. This is not at all worrisome. The oil's "40" (as in 0w-40) is determined at 212F so the oil is just barely over its nominal operating temperature at 230F. The elevated oil temperature helps remove water from the oil and that is a good thing.

Or if one leaves the town for the open road the oil temperature will drop some.

To someone not used to observing oil temperature in real time (and this applies to coolant temperature too) how oil temperature varies can be a bit of an eye opener. But as I was told when I asked the factory via a dealer about operating another car in elevated ambient temperature (116F) and the coolant temperature climbed to 226F and remained there that is if there is no warning light for low coolant level, no warning light for low oil level or elevated coolant temperature or low oil pressure, there is no problem.

 

[SKT PK 9 Man]

Ah ok yeah I will give that a try. That actually makes sense as half the tank is from circle k and the other half is from frys both 91 octane obviously. I really appreciate the response!

You got gas for your new Scat at Circle K??? Where do you get your oil? KFC? Poor car.

 

[scatpackfrank15]

I’ll have to try that next time. If it stops the vibrations would you happen to know what the issue would be? Or is this expected? I previously had an Rt challenger and never had an issue like this before but from other posts I’ve seen this may occur every once in a while.
Appreciate the reply!

that's a 392 gasoline should be at least 93 octane...exxon works well with hellcat...

 

[Gregdetroit]

You got gas for your new Scat at Circle K??? Where do you get your oil? KFC? Poor car.
[/QUOTE

that's a 392 gasoline should be at least 93 octane...exxon works well with hellcat...

unfortunately I don’t have any 93 octane gas stations within 50 miles of me. It’s all 87,89,91 octane

 

[19johned53]

unfortunately I don’t have any 93 octane gas stations within 50 miles of me. It’s all 87,89,91 octane

Factory recommend octane rating for the 392 is 91. Factory also states that up to 10% ethanol is acceptable.

 

[Gregdetroit]

Factory recommend octane rating for the 392 is 91. Factory also states that up to 10% ethanol is acceptable.

Oh I know I was just replying to a previous post to put 93 octane which I don’t have in my area. I put in 91 octane only

 

[Revtime]

91 is fine. Just make sure good quality gas.
Just throwing this out there but you should check the torque on the intake manifold bolts.
They may be loose.

 

[Sledder9]

that's a 392 gasoline should be at least 93 octane...exxon works well with hellcat...

"at least 93"? I mean, technically it needs "at least 91" not 93. Anything above is gravy.

 

[19johned53]

Oh I know I was just replying to a previous post to put 93 octane which I don’t have in my area. I put in 91 octane only

Yep, so was I. Put in the wrong post fast fingering!

My area is the same. 91 is the max available.

91 is fine. Just make sure good quality gas.
Just throwing this out there but you should check the torque on the intake manifold bolts.
They may be loose.

I should check mine. Been on my list, just ain't yet. Lol

A lot of folks have found loose bolts over the years. Pretty common I guess.

 

[Pioneer4x4]

...It happens when idiling (drive park...etc)...

Odd that it happens in Drive and in Park, totally different idling scenarios. In drive takes a lot more fuel/air than neutral/park does. So that probably rules out IAC type things and other engine controls.

 

[HEMI Eagle]

Hey all!
So I was driving my new challenger scat pack today and noticed after about an hour of driving i am noticing the car vibrate while at a complete stop. It happens when idiling (drive park...etc) however it’s not every time. The vibration also only last about 15 seconds or so then it goes away. Once I give it gas all is returned to normal no vibration. Also to be clear the vibration is a very low vibration I can feel it in my seat however it does not shake the vehicle at all. I have almost 600 miles on it and so far no issues. I’m giving it more throttle now that it’s over 500 miles but any ideas?

I also wanted to add it’s almost 100 degrees out today and I’ve noticed my oil temp change ever so slightly randomly.

Not to raise any eyebrows... just to confirm that my 2020 SP WB (over 13K Miles) does the exact same thing.
I'll pay more attention now that I know someone else has the strange "vibration".

Sitting at a stoplight in Drive. When it does it I can feel it in my seat, and I watch the idle but it doesn't seem to affect idle.
It's very audible... you can hear a change... it's very strange.

 

[Gregdetroit]

Not to raise any eyebrows... just to confirm that my 2020 SP WB (over 13K Miles) does the exact same thing.
I'll pay more attention now that I know someone else has the strange "vibration".

Sitting at a stoplight in Drive. When it does it I can feel it in my seat, and I watch the idle but it doesn't seem to affect idle.
It's very audible... you can hear a change... it's very strange.

Ok so I’m not alone! Lol

yeah it’s so strange but your right it’s a low vibration in the seat and you can easily here the difference. I haven’t noticed anything with rpms raising or lowering when it does it so that’s a good thing. I also had it happen to me going from park to reverse however once I gave it some throttle it stopped. I have a 21 sp wb just a little over 550 miles

 

[scatpackfrank15]

"at least 93"? I mean, technically it needs "at least 91" not 93. Anything above is gravy.

totally disagree..use the BEST you can find...