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Stu
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Discussion Starter · #1 ·
If your having a problem with your CMR tune/boost tune. Post the problem here for the CMR tuners to help you out.
God knows I need lots of help in that area... :cautious:
 

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This thread can get really crazy really fast. Boost and tuning has so many variables only way to tell is with files
 

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Stu
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21,316 Posts
Discussion Starter · #3 ·
An explanation would be very helpful on each tune problem.
Tune has 4 recurring problems that has been there from the very beginning of the tune revisions.

1. After driving the truck a few times after reset and re-install of tune. Rpm still hunts/surges at idle when stopping/stopped at a stop light???
2. Hunts/surges worsen with the a/c on. Why does it not do it as bad on the first few drives and then gets worse from there????
3. It's like the tune settings are backwards. So when the pcm makes adjustments to make the engine run better. It makes it run worse instead. ????
4. When driving 55+mph, let off of the throttle to slow down. The afr gauge shows a very rich condition. 12.2 to 10.0 afr. Could this condition be causing the pcm to change the tune/running setting????

Good note. Wot under boost, the tune is awesome and the 392 runs great even with just 6psi boost. Though, I know it needs adjustments. It still halls ass! (y)(y)(y)
It's just the recurring street driving problems that are driving me crazy... Everyone keeps saying that this 05 pcm is very tune able. It's not showing me that so far... (n)
 

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Stu
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21,316 Posts
Discussion Starter · #4 ·
1. After driving the truck a few times after reset and re-install of tune. Rpm still hunts/surges at idle when stopping/stopped at a stop light???
2. Hunts/surges worsen with the a/c on. Why does it not do it as bad on the first few drives and then gets worse from there????
3. It's like the tune settings are backwards. So when the pcm makes adjustments to make the engine run better. It makes it run worse instead. ????
4. When driving 55+mph, let off of the throttle to slow down. The afr gauge shows a very rich condition. 12.2 to 10.0 afr. Could this condition be causing the pcm to change the tune/running setting????
All these problems happen during 4 to 5 heat cycles (test drives). It doesn't make sense that the pcm is adjusting how the engine is running to making it run worse after 4th to 5th heat cycle. It should make the engine run better????
 

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regarding the surging....watch timing. If its dropping to a negative value, raise the min spark in that area to something like 0-2° and see if it helps.

Check dfco settings regarding the decel fueling.
 

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Stu
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21,316 Posts
Discussion Starter · #9 · (Edited)
regarding the surging....watch timing. If its dropping to a negative value, raise the min spark in that area to something like 0-2° and see if it helps.
Check dfco settings regarding the decel fueling.
Thanks Mike for your input.
Could the excessive fuel on decel be causing the pcm to change the tune?
Any Idea what causes the tune to go from running great to bad in a few heat cycles? It's like the pcm changes the tune or something? Have to erase the running history and re-install the tune to make it run good again. But, after some heat cycles. It's running bad again. That's the other thing that's driving me crazy... Any help or a explanation will be appreciated. Thanks.
 

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Sounds like something in the fueling model is off, and its chasing itself. The tune can't "change" once flashed to the pcm, and if its better after you reflash it again, its likely some sort of adaptive issue.
Is the injector data good?
Also confirm O2 sensors are functioning properly, etc.
 

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Stu
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Discussion Starter · #11 ·
80lb injectors @ 43.5psi fuel pressure. Running them at 62psif. That's what it was email tuned at. O2 sensors (oem from Dodge) have been changed out three times with no change on how it's running.
 

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Stu
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Discussion Starter · #13 · (Edited)
Put the O2's as close as possible in the factory locations on both right/left banks. Measured them out from the oem Y pipe that I still have.
 

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Stu
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Discussion Starter · #18 ·
Been talking to Dave at B&G. He says it's most likely it's the BBK 90mm throttle body. They have seen may problems with BBK throttle bodies. Recommended to go back to the oem throttle body. You don't need a big throttle body with a boosted street truck.
 
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