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Ford dealer tune "better" than Cobb Stage 3 93 Octane tune

yardlevy

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Fort Lauderdale, FL, USA
#1
Hey all,
not sure if this is the right place to post this but I am having a strange issue.
Last week I had to take my car to the dealer because it was stumbling and stalling. They diagnosed and replaced "Low side Fuel Pressure Sensor and Purge Valve". I also see "Recal PCM" on the report.

After picking up the car, I noticed the wrench indicator was on the dash, but the car ran well and the problem was fixed. In fact the car felt extra strong, and very willing to rev and seemed to have more power.
I have a Cobb Stage 3 setup and was running the 93 Octane tune, and I had not reverted to factory tune or uninstalled the AccessPort before taking the car to dealer. I was very happy with how the car was running and thought it was running better because of the fuel sensor and purge valve repair, but I was concerned why the wrench indicator remained on.

In an attempt to diagnose the wrench, I connected my AP and pulled the codes. I saw lots of active codes for fuel system issues( P0087, P008B, P018C, P0456, P1450,, and P2610) and thought these were from before the repair so I cleared code and also cleared learning. The wrench did not go away, but the codes cleared and did not come back.
However, after doing this, the car no longer ran as strong as it did when I first got it from the dealer. In fact, very soon after that the MPG reported had dropped from ~28 mpg which was where it was when I got the car back from the dealer to ~22mpg which was what I was normally getting with the Stg3 93 Octane Cobb tune. I flashed the Stg 0 tune and saw worse perf and similar MPG numbers. I flashed back to Stg 3 93 octane but still havent replicated how strong the car felt when I got it back from dealer. I smells like the car is running richer on the Cobb Stg 3 93Octane tune than whatever the dealer had changed.

Bottom line is I dont know what the dealer did to the PCM, but the car felt great and by clearing and reflashing the CObb tune I have lost those improvements. I want to understand what the dealer could have done and why it felt so much better than the Cobb tune. I will post readings from my AP guages and logging later.
 


Clint Beastwood

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#2
Just a thought - when my diverter valve plug cracked and wasn't connecting properly, the car ran super strong on the stock tune, didn't throw a code, and performance took a huge hairy dump when I flashed one of my other tunes on. After about a week, I checked codes and saw the code for DV valve malfunction, though no active CEL. I found the plug, fixed the cracked DV connector with uv resin, and went for a drive and performance was back to expected. I had also noticed a strong "fresh" (not burned) oil smell, and discovered that while the DV wasn't opening properly, oil was pushing out between the filter and the block ever so slightly. My other symptoms were similar to yours, with no dash CEL though - just a stored code. Something easy to check, just make sure the connector for your stock DV is attached, should be able to lay on the ground and reach under to confirm.

Also, the cobb tunes are kinda buttcheeks - they're kinda like the free samples at costco, they'll get you hungry but eventually you need to swing by for one of those 1.50 hotdogs and a churro ;)
 


OP
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yardlevy

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Fort Lauderdale, FL, USA
Thread Starter #3
Just a thought - when my diverter valve plug cracked and wasn't connecting properly, the car ran super strong on the stock tune, didn't throw a code, and performance took a huge hairy dump when I flashed one of my other tunes on. After about a week, I checked codes and saw the code for DV valve malfunction, though no active CEL. I found the plug, fixed the cracked DV connector with uv resin, and went for a drive and performance was back to expected. I had also noticed a strong "fresh" (not burned) oil smell, and discovered that while the DV wasn't opening properly, oil was pushing out between the filter and the block ever so slightly. My other symptoms were similar to yours, with no dash CEL though - just a stored code. Something easy to check, just make sure the connector for your stock DV is attached, should be able to lay on the ground and reach under to confirm.

Also, the cobb tunes are kinda buttcheeks - they're kinda like the free samples at costco, they'll get you hungry but eventually you need to swing by for one of those 1.50 hotdogs and a churro ;)

Thanks for the reply. I will check the DV. I have heard comments that the 91 octane Cobb tune feels stronger to some people --So I will try that too. I will pull the logs from the AP , but I dont remember if I logged the car before I cleared the codes :-(
I would like to understand empirically in the log data to confirm what my butt dyno was feeling.


I understand the Cobb tunes are kinda generic and was going dyno tune the car somewhere , but I dont know were I could source Fiesta ST tunes from other that Cobb. Any suggestions for good tunes for Cobb Stg 3 hardware( intake, intercooler, downpipe, exhaust)
 


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yardlevy

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Thread Starter #4
Thanks for the reply. I will check the DV. I have heard comments that the 91 octane Cobb tune feels stronger to some people --So I will try that too. I will pull the logs from the AP , but I dont remember if I logged the car before I cleared the codes :-(
I would like to understand empirically in the log data to confirm what my butt dyno was feeling.


I understand the Cobb tunes are kinda generic and was going dyno tune the car somewhere , but I dont know were I could source Fiesta ST tunes from other that Cobb. Any suggestions for good tunes for Cobb Stg 3 hardware( intake, intercooler, downpipe, exhaust)
After some digging thru the forums, seems like Randy from Tunewerks is a fave amongst the Ford Ecoboost folks. He also has a special where is offering custom tunes for stock turbo at $279 ( $100 off normal )
 


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#6
After some digging thru the forums, seems like Randy from Tunewerks is a fave amongst the Ford Ecoboost folks. He also has a special where is offering custom tunes for stock turbo at $279 ( $100 off normal )
Randy used to be THE GUY from Mountune. He did my tuning and have been very happy.
 


TyphoonFiST

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#7
Get a custom tune from Dizzy or another tuner. Also the wrench light just means oil change, there is a way to reset it. Check for a how-to on YouTube.
The "wrench" light can be reset with the Cobb ap3 *BTW
 


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