2016 mustang gt idle issue!!! Help!!!

[joeykitel]

So I just bought a used 2016 mustang gt.
I’ll start with info, it is a manual all stock besides exhaust.

I have an issue on a cold start when it’s been sitting overnight the idle will pulse almost like has a cam in it, that will last a couple minutes until it warms up a bit and drives completely fine, I don’t think it’s vct because I have no idle issues after it warms up or at stops but I could be wrong. Also zero codes I’ve tried finding other people with this issue and haven’t. Maybe someone can help me out.

so far things that I’ve checked or changed are
new spark plugs
New coil packs
New air filter and made sure it’s seated correctly
Cleaned the maf sensor
Cleaned the throttle body
I attached a video of the idle

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[joeykitel]

Sorry added the wrong video this is the idle

 

[ORRadtech]

Why would you discount the VVT?
It's an oil controlled system. The oil viscosity will be different cold and could cause idle issues.
Do you have any service records for the car? Neglected oil changes can cause VVT issues. Have you changed the oil/filter since getting it?

 

[joeykitel]

I’m not completely discounting it, just feel like my symptoms don’t line up with that issue when people have bad vvt it usually causes bad idle at anytime from what I’ve read, I have not done an oil change on it yet I will try that

 

[jowzi]

What you're describing very often corresponds to this problem: a vacuum leak that disappears when the engine is warm. A small air leak causes a lean mixture when the engine is cold; when everything heats up, the materials expand and the leak seals itself, which explains the subsequent perfect idle.

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[Cobra Jet]

Don’t discount VCT’s… they are not an”lifetime” part, they are a serviceable part on all of the Coyote 5.0 variants.

How many miles are on the car?


- VCT solenoids - if the solenoids are not operating properly due to debris or they are failing due to age, they can cause drivability and functional problems. Quite a few threads on here about these prematurely failing and/or how to diagnose.

The culprit here was the VCT solenoid::
https://www.mustang6g.com/forums/th...s-and-cam-retarded-codes.176734/#post-3571964

Here's (2) more threads for VCT info that I had previously posted in other threads:
https://www.mustang6g.com/forums/threads/2015-2021-s550-5-0’s-ssm-50067-vct’s-again-various-dtc-codes.169419/

https://www.mustang6g.com/forums/threads/p0018-code.123932/

The IMRC design has been problematic since the IMRC intake system first debuted in the 1994 Lincoln MKVIII with the 4.6 DOHC (which was then carried into the 1996 Cobra and beyond). Theres MANY threads on here regarding the intake and IMRC system.
https://www.mustang6g.com/forums/threads/possibly-broken-imrc-shaft.183221/#post-3689879

 

[joeykitel]

Update: changed all 4vct/vvt solenoids and nothing has changed even put a new MAF in just in case still have idle issue and now I’m getting random misfire codes

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