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S550 GT PP with P0345, P0349, P0300 and P0308 codes

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HalM3

EDGE Motorworks tests everything we install!
13
9
NorCal
AT 3,800 miles both cats failed and dealer replaced under warranty. Done several trackdays and every session ends the same way. Flashing check engine light, poor performance and when I limp the car back to the pits and pull codes get #8 misfire, random misfire and the cam bank2 and the intermittent bank2. I already tried using 91 octane fuel to see if it was a knock sensor issue and pulling all the timing it could out of the engine but not being enough and codes were set. The dealer installed 5W-30 oil and I think it was better but it was a cooler day than when it last occurred. Any suggestions?
 
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Is the engine stock?
 
898
544
I think you have one or more sensors bad and / or a possible short in the engine harness. The above points to a bad camshaft position sensor on bank A, bad crankshaft position sensor, or a short in the engine harness. It could be a combination of the same too, but it is probably just one of the three listed.
 

HalM3

EDGE Motorworks tests everything we install!
13
9
NorCal
Driveline is stock. I would NEVER mod a Ford under warranty. They have a nasty habit of denying warranty work after that...

Dealer has the car again for the third time. Now that the codes are stored it's in their hands now.

What viscosity of oil is everyone tracking?
What grade of fuel is everyone running?
 
898
544
Your codes don’t point to an oil viscosity or fuel issue. They also don’t point to a knock sensor. The cause of the codes you listed are typically a bad cam sensor, crank sensor, or a wiring issue.

For a stock tune, you should run 91 -93 octane based on the highest available.
 
I had a P0300 code for the first time this weekend at a trackday at Sebring. It's the 6th track day that it's been to. It was fine on Saturday, but threw a code on Sunday and the only thing that changed between the two days was the brand of fuel that I was using. They're both Tier 1 brands, so I'd be surprised if that was the culprit though. I cleared the code after the session and it came back on about 3 laps later.

The dealership cleared the code a few days later, but couldn't replicate it coming back on(obviously). He blamed it on the misfire counter, which 'learns' and adjusts to the way you drive the car. I called BS and said thank you very much. I'm sure that there are plenty of adaptive parameters in the engine code, but the misfire counter would not be one of them.

So that's a long way to say that I feel your pain, but can't offer a solution. Sorry.

PS - It's a '16 GT350 running 93-octane.
 

HalM3

EDGE Motorworks tests everything we install!
13
9
NorCal
Got a call yesterday that when the tech pulled the car in to begin work found that the phaser was backordered with a date of "30+." I told them I'll take a loaner car right now until the car is actually completed. This morning told they found they found the part in Richmond, CA and had already started teardown. They claim the intake manifold has no problems. We'll see...
 

HalM3

EDGE Motorworks tests everything we install!
13
9
NorCal
Car returned running fine. They claim they have no idea what failed and they just send the bad parts back. The next trackday at Thunderhill with BMWCCA will determine if they fixed it.
 
Am so Glad I don't track My Boss...I know I'm missing all the adventure..But I get my thrills when I can..Believe me!!! Son driving my Boss now has me worried..............especially with him selling his M3...:eek:...Grandma never took a Boss to church!!!!!!!!!!
 

HalM3

EDGE Motorworks tests everything we install!
13
9
NorCal
Car ran great all weekend. Cam phaser fixed it. Runs much better as well but one small problem, it has a small oil leak hitting the manifold and the burning oil smell. Still going back to the dealer but at least the problem was correctly identified.
 

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