Idk if it helps at all(coming from a non srt owner) but mine will also do that, but not as much. It will dip so low it seems like its going to die, and then flutters for a minute, and then everything is a-ok.
One thing is for sure, all this computer controlled, electronic garbage, is well... garbage..
My local dealership has asked a Chrysler Engineer to come and troubleshoot my car on Tuesday. Hopefully this can provide a more definitive answer to what is causing the RPM drop and fluctuation. A dealership Tech observed a similar idle drop and fluctuation on my car that you seem to describe. I asked if there was any sign of misfire and the Tech indicated that he observed nothing to indicate a problem with the injectors or plugs. The Tech recommended flashing the ECU. The ECU flash did not help the idle and the Technician is at a loss to explain why it is occurring. Has anyone noticed an accompanying knocking sound towards the rear of the engine when the idle drops low or fluctuates?
my car is practically stock and i get that also... I have just stopped paying attention to it altogether.. i can hear it in my exhaust.. but its just another part of this car i have to accept lol.
2008 Black pearl C-Srt4
Prototype Forge ext Bov setup
Prototype Forge wastegate (installed) 1st gear 10-12 psi, 2nd gear 15-17 psi, 3rd gear and up 17-18 psi all the way till redline.
ED Catless DP
4" Jmb Intake (installed 4-11-10)
Agp Breather Kit (installed 4-11-10)
Custom Muffler Delete
MS 1 installed (4-9-10)
MP race motor mounts (installed)
2008 Perf. white gt500 (sold)
2008 blue mustang gt (sold)
2005 mitsubishi evo8 (sold)
2001 Blown V6 mustang 340whp (sold)
I noticed mine was dropping from ~650RPM to <500RPM the first day I woke her from her winter nap. Sounded like it was going to stall, then it recovered.
Filled her up with good premium gas and took it for a hard run on through town and on the hwy.
My case, it may have been dirty plugs as it was running really rich before hand. That helped in my case.
I'd say take it for a good run, then pull the plugs to see what they tell you.
Well, it did it to me again today. I think it may also have to do with temps. Today it's pretty warm in S.Jersey, 78 degrees. I took a 12 mile trip and when I got to my destination the idle was bouncing up and down between 500-700 rpms. The AEM WB showed it going rich when the idle dropped each time as well (though that could be the computer adding fuel to avoid stalling).
When the rpms dip (near or slightly below 500 I DO hear a feint knocking sound from the engine). But I presume that is normal from such a rough low idle. It kinda like when you don't give it enough gas when taking off in first.
Another thing I noticed is, in general, the car isn't very smooth at low speeds in first gear- for example driving around a parking lot. It's very jumpy.
I wonder what the cause for this is??? I'd be quick to say it's something to do with MPS1 but some have mentioned they've experienced this on their stock vehicles. I also though it may have to do with my plugs (NGK iridium 1-step colder) though- again, I'm not sure everyone has these that is encountering this issue. It's quite annoying becuase at stop lights after a long drive it feels like I'm driving a clunker. I can even HEAR the rpms in the exhaust rhythmically when it happens as well.
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