Surging throttle

[SnakeMaster16]

If the car is under warranty take it in. This issue stems from a defect in the head itself, none of which would be attributable to the air intake changes you made. It does apply to a narrow range of build dates, 9/1/2020-12/1/2020 if memory serves. Look at your drivers valve cover sticker for your engine build date.

If the car is under warranty take it in. This issue stems from a defect in the head itself, none of which would be attributable to the air intake changes you made. It does apply to a narrow range of build dates, 9/1/2020-12/1/2020 if memory serves. Look at your drivers valve cover sticker for your engine build date.

Okay I will definitely check the build date. Anywhere I can see the TSB or what ever was sent out officially by Ford on the matter? Thanks

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[TW Merema]

https://www.mustang6g.com/forums/th...-0l-built-september-1-december-1-2020.165315/

See the thread linked above.

 

[TW Merema]

Sorry for the lack of any updates here. I’ve been trying to get this thing fixed since June, and I’m now on my second dealership. These fools can’t diagnose crap, and when they do they order the wrong parts, then when they get the right parts, they don’t have the manpower to fix it. Second dealership took 3 weeks to get an appointment, and when I took it in today lo and behold they couldn’t diagnose because there is no active check engine light. Stored codes aren’t good enough. Frankly I’m getting fed up with the $hit service out of anybody these days, and I’m about ready to set this POS on fire. Once I get a resolution I’ll post it here. Opened a case with Ford to try to get it fixed, they are about as useful as tits on a bull.

 

[TW Merema]

Car is in the shop this morning. Hopefully this issue is resolved by end of week. I’ll let y’all know.

 

[TW Merema]

Have the car back after 8 days. They replaced the cylinder head, and it seems to have solved the issue. I’ll post a pic of the repair sheet later for those that are interested. Thanks for following along!

 

[TW Merema]

 

[Conman1138]

Have the car back after 8 days. They replaced the cylinder head, and it seems to have solved the issue. I’ll post a pic of the repair sheet later for those that are interested. Thanks for following along!

That's great news! I'm glad a solution was found.

Did your dealership techs have any theories as to what the cause of the problem may have been? When I had my engine replaced for this problem, the dealer techs theorized that it may have been a defect in oil passageways causing surges of oil pressure to reach the intake cam phaser. My old engine went back to Ford for a teardown, but I never heard anything after that.

 

[TW Merema]

They didn’t offer any opinions, however, the SSM bulletin mentioned a “flatness issue” on the mega cap. To me, that says there was a machining issue with a certain batch of heads and the caps were not square to the heads. When torqued down, they probably let oil pressure escape where it shouldn’t, which caused the VCT to shift when it wasn’t supposed to. This seems likely, since certain times while driving the car would feel way down on power until 5k rpm, at which point there was a huge surge in power. My thinking is the oil pressure retards the low rpm timing, and it defaults to the high rpm timing when pressure isn’t high enough? During those episodes it also idled like it had a cam in it, very lumpy and rough idle. You could literally see the movement if you looked at a fixed reference point.

 

[TW Merema]

I wonder how they determined it was a head issue. Meaning, ok you have a cylinder down on compression (just assuming) or maybe valve blow by (bad seating valve) I guess leak down?

As mentioned in the SSM I don’t believe it was a valve sealing issue, more a VCT problem with the timing. The codes I was getting pointed to the cam sensor on bank #1, exhaust cam so that likely was the solenoid that was unstable due to fluctuating oil pressure.

 

[Conman1138]

They didn’t offer any opinions, however, the SSM bulletin mentioned a “flatness issue” on the mega cap. To me, that says there was a machining issue with a certain batch of heads and the caps were not square to the heads. When torqued down, they probably let oil pressure escape where it shouldn’t, which caused the VCT to shift when it wasn’t supposed to. This seems likely, since certain times while driving the car would feel way down on power until 5k rpm, at which point there was a huge surge in power. My thinking is the oil pressure retards the low rpm timing, and it defaults to the high rpm timing when pressure isn’t high enough? During those episodes it also idled like it had a cam in it, very lumpy and rough idle. You could literally see the movement if you looked at a fixed reference point.

Very interesting! Now I'm wondering if a head replacement would have solved it for me, too. My dealer went straight from replacing cam phasers to replacing the whole engine on recommendation from Ford engineering. Maybe they knew less about the cause of this particular issue 3 years ago.

I bought my car used, but I got to break in the new engine myself, so it worked out in the end!

 

[Cobra Jet]

They didn’t offer any opinions, however, the SSM bulletin mentioned a “flatness issue” on the mega cap. To me, that says there was a machining issue with a certain batch of heads and the caps were not square to the heads. When torqued down, they probably let oil pressure escape where it shouldn’t, which caused the VCT to shift when it wasn’t supposed to. This seems likely, since certain times while driving the car would feel way down on power until 5k rpm, at which point there was a huge surge in power. My thinking is the oil pressure retards the low rpm timing, and it defaults to the high rpm timing when pressure isn’t high enough? During those episodes it also idled like it had a cam in it, very lumpy and rough idle. You could literally see the movement if you looked at a fixed reference point.

Interesting result and findings. I say that because I actually posted the SSM 50103 back in December 2021 - but never wouid have guessed that was the actual issue for your vehicle.

If anyone needs it, here is the SSM for the mega cap issue:
https://www.mustang6g.com/forums/th...flatness-on-mega-cap-rh-cylinder-head.169407/

 

[TW Merema]

Unfortunately the saga continues, the car had an oil leak where the timing cover meets the oil pan. So after 8 days in the shop, it’s been in there another 2 days. They tell me it should be done tomorrow. I don't think I have to say I’m beyond frustrated with this, and even as a lifelong Ford guy I don’t think I’ll ever buy another one new if this is the level of service I should expect. Never had an issue pre-Vid, now it’s like herding cats trying to get this effing thing fixed.

 

[TW Merema]

Car is back, took them 3 days to correct the oil leak, it was where the front cover meets the oil pan. If anyone else has this repair done make sure you check that spot for oil leaks. It drips right on the steering rack control box, then down into the belly pan.

 

[Mike-S550]

Have the car back after 8 days. They replaced the cylinder head, and it seems to have solved the issue. I’ll post a pic of the repair sheet later for those that are interested. Thanks for following along!

So, you’re saying it wasn’t the cat back? /s
Glad you got this sorted, op.

 

[Conman1138]

Car is back, took them 3 days to correct the oil leak, it was where the front cover meets the oil pan. If anyone else has this repair done make sure you check that spot for oil leaks. It drips right on the steering rack control box, then down into the belly pan.

Man, I really hope this is the end of the problems for you!

FWIW, mine has been rock solid reliable since engine replacement for more than 30k miles now.

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