ballscout1

My 2015 Mkz is making a strange noise. When starting the car it makes a noise like something broke loose but then settles down.

If I rev the motor upon releasing the throttle there is a loud whirring sound.

Sounds like it is under the valve cover but hard to locate
 

It idles fine

it drives and accelerates fine|

No DTC codes or check engine light

I will try to use a recorder on my phone to post it.

I ordered a couple of these 

https://www.amazon.com/gp/product/B078J55SBW/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&th=1

I have a 2015 MKZ and the backup camera only works when cold out. When it's warm/hot out the camera doesn't come on.

Since it works fine in the cold, I assume it is not the camera. I also upgraded from Sync 2 to Sync 3  with the same symptoms.

How about pictures of the wiring connections and locations to check?

I have a 2015 MKZ and about a year ago I upgraded my Sync 2 to Sync 3. I have been reading this topic and others like it for the last couple of months and decided to try my hand at upgrading the modem to 4g.

Well, today I did it, and although there were some things I couldn't figure out I got through it without bricking the modem or my car.

 I couldn't find a Hj5t-14g087-uf modem at a reasonable price so I decided to give it a go with a jl3t-14g087-cf.

So Start Stop Lock and Unlock work and it monitors fuel level, oil life and tire inflation.

I couldn't figure out how to monitor the TCU to  see signal strength and the status of the module among other things

Also, I saw images that in addition to start and lock and unlock also had lights and horns.I don't have those.

I also saw it mentioned that you had to plug in your old antennae cable as well as the $g cable but my old cable didn't fit on the tan connection so I only have the  4g antenna attached to the purple connection on the modem.

I do have a GPS antenna that was installed in the front of the car when I upgraded Sync.

Anyway, I am excited it worked and want to thank each one who spent their time sharing info and instructions so that those of us with no clue could make this happen.

Thanks so much and enjoy your holidays