smooth smooth then rough shakey type idle HELP?

**rcboarder76** · 04-02-2009, 11:59 AM

hey guys i have an 07 charger r/t with 93 canned tune diablo, kool vue cai, and slp lm1's....
also changed the spark plugs to bosch platinum 2's 3000 miles ago... not sure how long its been doing this but sitting in park idling its smooth then it fells like it shakes which i noticed pretty well and it only does it for about a second then its smooth again. and if my lights are on and a/c u can see them dim for a second and the a/c blows slightly less... not surewhat it could be..... PLEASE HELP its annoying... p.s. there are no codes being thrown or lights coming on for anything being wrong

**rcboarder76** · 04-02-2009, 06:46 PM

any help??? any ideas!

**SilvaSurfer** · 04-02-2009, 07:04 PM

2 ideas for you, #1 when was the last time you clean the Throttle body? #2 (multi-part) What type of gas are you using and were the spark plugs gaped correctly? Someone else can chime in as well.

Suggestion: try putting the old plugs back in and see if it goes away..

**rcboarder76** · 04-02-2009, 07:10 PM

never cleaned the throttle body.... and i dont have the old plugs but im thinking about going back to the stock ones... what brand are the stock ones again and where can i get them?

any other ideas on what it could be...

**rcboarder76** · 04-02-2009, 07:11 PM

also the plugs were pre gapped and the car has 32,400 miles and i use 93 chevron gas

**Bagged Mag** · 04-03-2009, 01:35 AM

ive noticed this in my mag. just thought it came with a noticible idle, i mean it is an 8 cyl. first one that ive owned.

**EmagdniM** · 04-03-2009, 11:54 AM

Never trust pre-gapped plugs. Ive bought them many times to find them wayyy off...Id pull the plugs and doublecheck the gaps first.

**EmagdniM** · 04-03-2009, 11:57 AM

Also, are you sure the shutter isnt caused by your a/c condensor switching on? Or maybe a cooling fan coming on?

**Hemi31** · 04-03-2009, 12:03 PM

Does it do it on the stock tune or only on the Diablo?Sounds like the old stumble from the 05' cars.

**Bagged Mag** · 04-03-2009, 01:27 PM

Originally Posted by Hemi31

Does it do it on the stock tune or only on the Diablo?Sounds like the old stumble from the 05' cars.

my mag has the stock tune. so the 05 are known for this? i should have some down time this weekend. ill check out my throtle body and plugs and update with results.

**Hemi31** · 04-03-2009, 01:39 PM

Originally Posted by notorious170

my mag has the stock tune. so the 05 are known for this? i should have some down time this weekend. ill check out my throtle body and plugs and update with results.

Yeah the 05's had a TSB for this and needed a reflash on the PCM.