Running Rich

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MGMSHO

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Car has been running rich lately. You can smell the fuel and exhaust tips are always covered in thick soot.
Had a friend mention it might be my map sensor, so i cleaned it but nothing has changed.
As for mods I have installed the airaid intake, Ford Performance Touring exhaust, EPP Hot pipes, and BOV adapters. I've replaced fluids, changed out spark plugs, and purge valve.
Any guidance would be greatly appreciated. The car has 67K miles and is a weekend car so isn't driven much. I use only 91 octane fuel as well. Thanks crew.
 

76FoMoCo

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Injectors or bad 02. Pull the plugs and see what cylinders are rich
 

BradM

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Also check what the temp sensor is reading in case it's not working. That'll give you rich tables.
 

BradM

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Coolant temp. If the engine thinks it's cold, it will add fuel.
 

SM105K

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Yes it would. Pull the code and see what the check engine light is.
 

MGMSHO

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Yes it would. Pull the code and see what the check engine light is.
well thats whats confusing is there is no engine light. come to think about it, when i last had my ptu fluid changed, thats when this started. would there have been anything messed with when the dealer mechanic removed the cat to access the ptu?
 

BradM

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I can't think of anything the mechanic would do to cause running rich that wouldn't throw a code. By the way, black soot on the exhaust tips is normal for ecoboosts.
 

kryptto

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I can't think of anything the mechanic would do to cause running rich that wouldn't throw a code. By the way, black soot on the exhaust tips is normal for ecoboosts.
What if the mechanic disconnected the DP and possibly damaged the O2?
 

Joshw0000

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well thats whats confusing is there is no engine light. come to think about it, when i last had my ptu fluid changed, thats when this started. would there have been anything messed with when the dealer mechanic removed the cat to access the ptu?
My guess is that the dealer did an ECU "update" when they serviced it. I had it happen to my old Mustang shortly after I bought it. The previous owner had installed a Roush S/C, along with other upgrades. I test drove it, bought it, and drove it home. On the way home, I got a couple CEL's (charging system and something else) so I went straight back to the dealer and demanded they fix or return it. Long story short, when they fixed it, they flashed the latest stock ECU update which overwrote the custom tune. I didn't initially realize that it had lost power and was running rich. I drove it that way for about 3 months. I fouled plugs and ruined a cat before I realized what had happened. Getting it re-tuned fixed the problem, which in my case was expensive because I didn't have the tuner/file from the original owner.

Moral of the story is never let a dealer work on your modified car unless you personally know / trust them. At the very least, get a ODB port cover and make the rep note on your service ticket not to update the ECU.

That's why I asked if it was tuned. If it's not, you probably should get it tuned. If it is, reflash your custom tune and see if that helps. There's a good chance your car has been restored to factory ECU settings.



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SM105K

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Car has been running rich lately. You can smell the fuel and exhaust tips are always covered in thick soot.
Had a friend mention it might be my map sensor, so i cleaned it but nothing has changed.
As for mods I have installed the airaid intake, Ford Performance Touring exhaust, EPP Hot pipes, and BOV adapters. I've replaced fluids, changed out spark plugs, and purge valve.
Any guidance would be greatly appreciated. The car has 67K miles and is a weekend car so isn't driven much. I use only 91 octane fuel as well. Thanks crew.
I see the mods in you previous post. Is your car tuned?
 

BradM

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I just don't see the dealer even plugging into the OBII port if the car is in just for fluid service. Grab your reader and get some data would be my next step. Fuel trims, coolant temp.
 

Joshw0000

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You'd be surprised. His car isn't tuned so that doesn't matter now.

I totally agree about data logging. My MPG dropped last year and I could tell I had an issue as every time I refueled (and only when I refueled) the car took longer to crank. I watched the AFR on my tuner and could see it was out of whack.

I started with a New Vapor Canister Vent Solenoid - Duralast PV515 (Ford 8G1Z 9F945 A). That didn't fix it. Then I replaced the Vapor Canister Purge Valve (9U5A-9G866-DC) and that fixed it. My SHO is a 2012 so anyone looking to replace theirs, double check the part numbers ('10 - '12 SHO's are the red-headed SHO step child).

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MGMSHO

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You'd be surprised. His car isn't tuned so that doesn't matter now.

I totally agree about data logging. My MPG dropped last year and I could tell I had an issue as every time I refueled (and only when I refueled) the car took longer to crank. I watched the AFR on my tuner and could see it was out of whack.

I started with a New Vapor Canister Vent Solenoid - Duralast PV515 (Ford 8G1Z 9F945 A). That didn't fix it. Then I replaced the Vapor Canister Purge Valve (9U5A-9G866-DC) and that fixed it. My SHO is a 2012 so anyone looking to replace theirs, double check the part numbers ('10 - '12 SHO's are the red-headed SHO step child).

Sent from my Pixel 7 Pro using Tapatalk
 
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