Check engine light flashing, running rough.

[Saberranger]

My wife was on her way to work yesterday when the check engine light on our 2015 Sho started flashing and the car started running very rough and had hardly any power.

She drove it to my work just a few miles away so she could swap for my truck.

When I got off work I drove the Sho and it is indeed running very rough and the engine light is flashing.

When at an idle it shakes and you can see the rpm’s wandering.

I babied it and got it home. I had it towed to my local for dealership today.

When the tow truck driver was getting his chains on he noticed this arm underneath was disconnected from the frame.

I got underneath and it is, the same arm on the other side is disconnected.

Is this part of the engine mount?

The can not find any diagrams to see what exactly this part is.

Background on the Sho. It was a one owner, owned by an older couple before I bought. It was meticulously maintained.

It had around 78,000 miles on it and I’ve never had any issues with it for about the year that I have owned it.

 

[kryptto]

That is hard for me to get a good understanding of what you are seeing. However I am not aware of a chassis part causing an engine to run rough. You will know soon enough once they hookup the diagnostic and pull the error.

 

[FREAK_SHO]

That circled part appears to be the plastic undertray/belly pan. Those are notorious for the being/ coming loose for one reason or another, especially the rear. Missing screw and or missing attachment nut.

 

[kryptto]

That circled part appears to be the plastic undertray/belly pan. Those are notorious for the being/ coming loose for one reason or another, especially the rear. Missing screw and or missing attachment nut.

OK glad you said it, I replaced mine and bought extra parts like the grommet.

 

[SHOrod]

Assuming the front of the SHO is to the left of that first image, the circled item definitely appears to be the plastic belly pan rather than a structural component. It doesn't really appear to be drooping enough for it to be missing the half-turn screws, so that would be good news.

A flashing check engine light should indicate an emissions-related issue, consistent with a misfire or vacuum leak that would also cause the engine to run roughly. If you're lucky, some of the intake air tubing came disconnected, or possibly a sensor came unplugged. Less lucky would be a bad coil or spark plug. And even less lucky, well, let's not think that negative right now.

-Rod

 

[Junkyard_Mad-Scientist]

I agree with the consensus that the part pictured is the belly pan, essentially there for airflow and catching drips, not essential I removed mine completely. as for the flashing CEL, as @SHOrod said, flashing is usually related to a misfire. 3 main components of internal combustion, fuel, air, and spark, when one fails it creates a misfire. unfortunately on these cars there is more than a handful of reasons a misfire can occur (I chased one for 4 months). I suggest systematically checking each system, start with Air, a loose clamp or torn intake boot can create an issue. from there you come to an even fork in the road:

Ignition/Electrical: Plugs, Coils, Wire harness and connector condition, map sensor(s)
Fuel: Low pressure fuel pump, low pressure fuel pump computer (in trunk), fuel injectors (very common especially around 100k), high pressure fuel pump

Of course there could be something not listed causing it, the rabbit hole goes deep but these are the more common things I would and have checked and have seen cause trouble for others here. She looks like a clean SHO, Red with no sunroof option, definitely a keeper.

 

[Saberranger]

I could have sworn the part that I have pictured was metal when I felt it, but then again I was quickly looking at it before it went on the tow truck.

 

[kryptto]

Let us know what the shop tells ya

 

[Saberranger]

Let us know what the shop tells ya

Will do, I’m hoping to hear from them today.

 

[BradM]

I could have sworn the part that I have pictured was metal when I felt it, but then again I was quickly looking at it before it went on the tow truck.

It's metal. It's designed to be removable with no tools (twist connectors). They can come loose or not be fully seated when attached.

 

[BlindAssassin111]

It's metal. It's designed to be removable with no tools (twist connectors). They can come loose or not be fully seated when attached.

The one on my car is 100% plastic, and that should be true for all SHO's and from what I can tell the PI's have a metal skid plate which is why yours is metal.

 

[Texas Marauder]

The PI skid plate is much smaller and bolted on. It mainly protects the catalytic converter.

 

[Saberranger]

Finally got a call from my Ford dealer today.

A rodent chewed part of the wiring harness. Luckily they are able to fix it without having to replace the harness.

Going to cost about $800.

It’s odd that a rodent could gotten in. My wife drives the car every day and uses it for deliveries.

 

[kryptto]

Finally got a call from my Ford dealer today.

A rodent chewed part of the wiring harness. Luckily they are able to fix it without having to replace the harness.

Going to cost about $800.

It’s odd that a rodent could gotten in. My wife drives the car every day and uses it for deliveries.

We have heard of many of these rodent wiring harness issuea

 

[SHOrod]

I'm not sure how much truth there is to it, but I've heard that Ford, as well as a few other manufacturers, use a soy-based insulation on the wiring harnesses in an attempt to be more environmentally friendly, but it's apparently quite tasty for rodents. Seems like maybe they could impregnate it with a bittering agent or something that would repel rodents....

 

[Junkyard_Mad-Scientist]

I'm not sure how much truth there is to it, but I've heard that Ford, as well as a few other manufacturers, use a soy-based insulation on the wiring harnesses in an attempt to be more environmentally friendly, but it's apparently quite tasty for rodents. Seems like maybe they could impregnate it with a bittering agent or something that would repel rodents....

I've heard this same thing for a few reputable mechanics

 

[kryptto]

I've heard this same thing for a few reputable mechanics

I am gonna order used wiring harnesses from eBay, boil them in water for ten minutes and start my diet.

 

[Junkyard_Mad-Scientist]

I am gonna order used wiring harnesses from eBay, boil them in water for ten minutes and start my diet.

Even cars are going gluten-free these days

 

[kryptto]

Even cars are going gluten-free these days

Eating wiring harnesses is the new ramen