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Discussion Starter · #1 ·
Not only was the install difficult, but it seems that there is a surging of the rpms. When the car slows down the rpms stay at about 1500 (almost like the gas pedal is still pressed) and eventually goes lower when the car completely comes to a stop but not before there is a surge of the rpms at around 1100. It goes up and to about 1200 and then goes down to idle. I have disconnected the battery 2 times and also pulled fuse 11 once. Has the happened to anyone else? What could be causing this issue. I am really starting to believe this whole exhaust change was a big mistake.

HELP!!
 

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JohnnyVIG...

first time I have heard of this one...
PM bottlefed1500 and get the answer direct...
good luck!
 

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No issues on my install, either. Richard took the car outside and left it running for about 10 minutes to burn off the oils used in the pipe bending. Its idle was rock solid.

On a side note, I am having a idle surge problem with our SRT8 right now. It has gotten colder at night and at first start in the morning(garage isn't heated) it will hunt for the idle. It will almost die, then rev up to 800rpm or so, then do it again. Once it reaches operating temp it becomes rock solid. It is going to the service department this week.

Todd
 

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Discussion Starter · #4 · (Edited)
WhiteDiamond said:
No issues on my install, either. Richard took the car outside and left it running for about 10 minutes to burn off the oils used in the pipe bending. Its idle was rock solid.

On a side note, I am having a idle surge problem with our SRT8 right now. It has gotten colder at night and at first start in the morning(garage isn't heated) it will hunt for the idle. It will almost die, then rev up to 800rpm or so, then do it again. Once it reaches operating temp it becomes rock solid. It is going to the service department this week.

Todd
Idle is perfect, my surging is when the car is decelerating, when the rpms go down they hang at 1500 then drop to 1100 then back up to 1200 then they go down to idle. System is welded, clamps weren't tight enough.I can't imagine an exhaust leak would cause this. Maybe I need to re-program the drive by wire gas pedal procedure.

P.S. I CHECKED AND THERE ARE NO CODES PRESENT
 

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Johnny Vig said:
Idle is perfect, my surging is when the car is decelerating, when the rpms go down they hang at 1500 then drop to 1100 then back up to 1200 then they go down to idle. System is welded, clamps weren't tight enough.I can't imagine an exhaust leak would cause this. Maybe I need to re-program the drive by wire gas pedal procedure.

P.S. I CHECKED AND THERE ARE NO CODES PRESENT
Hope what I PM'ed you might help ... There is really nothing exhaust related that woud cause issues as you describe. My only other concern is that the car's battery was disconnected while isntallation occured ... we recommend that on all installs ... especially when welding. Check with your dealer .. they really should have no objection to working onthe car in its condition with aftermarket exhaust.

Richard
 

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Also, make sure you hooked the grounding strap back up. There is a grounding
strap on the rear portion of the exhaust, that is supposed to go between the
exhaust and one of the metal hangers that is located on the passenger side of the
car, at the very back.

This strap is made up of a thick wire braided material, with a clip at each end that
snaps over the round metal hanger, and one of the metal hangers on the exhaust
pipe. Its there to ground the exhaust since the exhaust is isolated at the rear by
the rubber loops.

If you did not re-attach your ground strap, try that. It might help.

Jim
 

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Discussion Starter · #7 ·
Ground strap is on.

Btlfed1500 I think you meant to say the battery was not disconnected when they welded the exhaust. Is that what you meant? Either way, what could happen if it wasn't?

P.s. The surging seems to have diminished for the most part. Rpms jump when the car is downshifting thru the gears as you come to a stop. This is normal. I just need to know if everyones srt 8 hangs around 1500 rpms when you let off the gas above 60 mph or so. Maybe this is part of the tranny programming?
 

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Johnny Vig said:
Ground strap is on.

Btlfed1500 I think you meant to say the battery was not disconnected when they welded the exhaust. Is that what you meant? Either way, what could happen if it wasn't?

P.s. The surging seems to have diminished for the most part. Rpms jump when the car is downshifting thru the gears as you come to a stop. This is normal. I just need to know if everyones srt 8 hangs around 1500 rpms when you let off the gas above 60 mph or so. Maybe this is part of the tranny programming?
It is not all that common but it has been observed in some cars that high current, like that used for welding, can cause partial or complete PCM failure should a short ever occur. It is precautionary to disconnect the battery or use some sort of short circuit failsafe attached to the battery when welding.

As far as the rpm issue their wil be a slight relearn phase but a lot of the behavior you are speaking of is infact normal.

Richard
 

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Discussion Starter · #9 ·
btlfed1500 said:
It is not all that common but it has been observed in some cars that high current, like that used for welding, can cause partial or complete PCM failure should a short ever occur. It is precautionary to disconnect the battery or use some sort of short circuit failsafe attached to the battery when welding.

As far as the rpm issue their wil be a slight relearn phase but a lot of the behavior you are speaking of is infact normal.

Richard
Thanks again for all your help. It means alot to have the manufacturer concerned about making sure everything is ok and the customer is satisfied.

As far as the re-learn, how many miles do you think it should take?

All other car functions are normal and there are no codes present. The idle is perfect at 650-700. Once again the difference I feel is when I get off the gas pedal at or around 60mph or in 5th gear. It seems the tranny and or its programming wants to keep the rpms cruising at 1500 I guess to avoid them going to low to quickly and then havign to downshift quicker than normal if the driver hits the gas again. My Corvette drops the rpms immediately and the tranny does a lot of gear hunting. On the SRT8 the rpms will go down as the car comes to a stop only jumping a bit when the car downshifts which of course is normal. I tested this out in auto-stick by beign in 5th gear and then letting the car coast and it did slow down a little quicker and the jumps in rpms when the car did downshift on its own were a little less prominent. Once again, I need feedback from other SRT 8 owners on how their cars and the tranny shift points and rpms react.
 

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JohnnyVIG...

So I drove in "D" for you yesterday...
and the rpm's do "bobble" a bit...
but there is no noise increase to speak of...
you notice the little things don't you?
not a knock - I just never noticed what you are talking about until you called me and asked me to look at mine as well...
I would have to say that it did it prior to the Magnaflows going on...
try autostick sometime!
and let that thing rip!
it's only gas...
 

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Discussion Starter · #11 · (Edited)
cbutler32 said:
So I drove in "D" for you yesterday...
and the rpm's do "bobble" a bit...
but there is no noise increase to speak of...
you notice the little things don't you?
not a knock - I just never noticed what you are talking about until you called me and asked me to look at mine as well...
I would have to say that it did it prior to the Magnaflows going on...
try autostick sometime!
and let that thing rip!
it's only gas...
I luv ya brother, you have a way with words and truly put things into perspective.

When you say bobble, did the car feel like it was on cruise control for a little bit around 1500 rpms at about 60mph even though your foot was off the gas? I don't have any different noise, I just hear the exhaust because it is now louder. Once again it may be normal in which case I can start sleeping again......Thx for your help.
 

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same prob

Johnny Vig said:
Not only was the install difficult, but it seems that there is a surging of the rpms. When the car slows down the rpms stay at about 1500 (almost like the gas pedal is still pressed) and eventually goes lower when the car completely comes to a stop but not before there is a surge of the rpms at around 1100. It goes up and to about 1200 and then goes down to idle. I have disconnected the battery 2 times and also pulled fuse 11 once. Has the happened to anyone else? What could be causing this issue. I am really starting to believe this whole exhaust change was a big mistake.

HELP!!
i have the same problem with my 06 300c.. after i had the the flowmasters installed.. it has the exact same problem; with the low intermittent idle and cut off. i never had the problem until i added the exhaust.. i wonder if some sensor needs to be replaced or if something was damaged during the install. the weather is colder now so i haven't had that problem lately.
 
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