P3D+ Issue: Front Undercarriage cover came loose (while driving)

[satlus]

Hi all,

First post. I took delivery of a P3D+ on 9/27. I've been absolutely awestruck with how well this thing drives, and have been driving way more as a result. Decided to go for a 110 mile trip with the family on Sunday, and about 60 miles from home, I hear a fluttering noise that is clearly coming from the front of the car. This is happening on a two lane highway, so I immediately get the hazards going, slow down to 35mph and the noise subsides. I pull over at the nearest exit to assess the situation. On visual inspection it appears the composite under carriage cover (that covers the front suspension), is completely loose at the front, with missing bolts/washers. When I took a closer look it seemed most of the bolts were loose! I had done an under carriage visual "spot check" when taking delivery of the car, it definitely did not look like this. There was also zero evidence of damage/impact that could've caused it - the bottom of the car is smooth as glass. Some pictures:




I called Tesla roadside assistance, they offered a towing service and drop-off to the nearest service center. I realized this was going to be an all day affair and decided to limp to a gas station to see if anything could be done. I made it to the station without issue, and came up with the lackluster solution in the pic below:



Yes... that's duct tape. It was strategically placed so that it provided a lip over the dangling cover that could be further supported by airflow at speed. The solution worked well enough; it allowed us to drive at a safe minimum speed on the highway to get home.

Has anyone experienced anything even remotely similar to this? When I was on the phone the roadside rep seemed to indicate that this cover coming loose "dragging" had been something that other owners experienced. My limited forum and google searching hadn't turned anything similar up.

Last bit is the service center - they seem completely inundated post the Q3 delivery push. I want the car to get on a lift and be fully inspected as this does not instill confidence (although aside from this issue the car feels incredibly well built with zero rattles/shakes/ etc). The earliest they can take it in is two weeks from now. At the least I'd like to get some compatible bolts and washers to see if it this could be temporarily secured more robustly. I'm super disappointed in this quality control, especially considering this is the premium version of this car.

Any thoughts/comments/feedback/advice by those more knowledgeable than is greatly appreciated.

 

[Drax]

I’ve had this happen on several cars. I get the disappointment, but don’t sweat it too much.

The 2 week wait for a service appointment is certainly something else though.. TBH, if you’re relatively close to your SC, I’d just show up early in the morning and ask them to take a look at it. I’ve had good luck for relatively minor issues with my S and 3.

 

[satlus]

Appreciated - rolling up to the SC early sounds like the smartest option, I'll give it that shot.

 

[gringotuanis]

Appreciated - rolling up to the SC early sounds like the smartest option, I'll give it that shot.

Not sure where the bolts and washers are...I work on boats with varying levels of manufacturing and it's critical to use the blue loctite on screws and bolts on boats especially. The rattling and vibration of the motor, propeller and water tends to loosen them. I've seen pontoons where most of the fencing screws have to be retightened due to this or the type of road it was towed on(gravel, etc). I would ask the service center to put the blue loctite that you can unscrew by hand later onto the bolt threads. You don't want the permanent loctite stuff or they won't come out even if the cover needs to be unbolted. If this is just plastic protective cover this should work well and you probably won't see the issue again. Disclosure long tsla via stock and options.

 

[satlus]

Update - I unscrewed one of the loose bolts/washer and measured it with my digital calipers. Did some googling and found a match with this part:
Crown Bolt M6-1 x 25 mm Metric Body Bolt - GM with 24 mm Washer-75518 - The Home Depot

Picked up a half a dozen, and was able to secure the front of the shield where the previous bolts fell out (only needed 3). The front right of the shield is damaged from road rash (eyelet for the bolt was worn off), but that's minor. I test drove the car, was no problem up to 70mph - it's good enough to tide me over until the service center can replace it. I also tightened the existing bolts, and two nuts (all were loose).

Picking up the parts in my ICE vehicle, then going for the test drive after the fix reminded me why this is all worth it in the end

gringo, loctite is a must - I have ton of the stuff for my RC hobbies I'm annoyed the bolts were not properly torqued from the factory, even without loctite they should not be loose at ~150mi on the car.

 

[JeremyB84]

Wow, I took delivery of my P3D the same day as you and this just happened to me on my drive home from work today with 25 miles to go. Your photos look exactly the same and I even applied duct tape the same way you did to get home. Really frustrating and an extra inconvenience in my life I don't need.

 

[Zoglog]

Just got delivery of mine. Will look out for this. Thanks for the heads up

 

[AlanSubie4Life]

I took delivery of my P3D+ with one of the 4 bolts missing, this weekend. It went on the due bill. I’ve been meaning to tighten/check the remaining bolts. Seems like I should do that now!

It’s definitely something to be checked during delivery inspection. Also there are multiple bolts in the rear to check for. I saw a brand new car at the delivery center with both of the bolts missing in the rear (there are probably more bolts). I think this contributes to the rear bumper getting ripped off, eventually. In the rear there is a middle hole which doesn’t get a bolt, there is no hole.

 

[AlanSubie4Life]

I checked my front bolts with my torque wrench. The three remaining front bolts were tightened to less than 25 inch-lbs. That is the minimum setting on the torque wrench. This is not tight! I tightened them to 36 inch-lbs. This is also not tight. I don’t know whether they screw into aluminum or something silly like that so I don’t want to push it. I’ll ask them to tell me the torque spec on these bolts when I take in the car to get the missing one added. It seems to me a bolt tightened like this without being seated on anything is likely to walk itself loose. So a mild threadlock might be good. But I am not an expert on the physics of fasteners.

Front sheet: 8 total fasteners into the sheet edges. 10mm bolt heads. There are other 10mm bolts as well but they are going to other stuff. Everything seemed pretty loose and in danger of rattling free.

Rear sheet: 6 total fasteners into the sheet edges. 10mm socket. There are also two bolts into the plastic rear diffuser, and a hole with no bolt. All these seemed fairly loose as well.

Though I did modestly tighten, I wouldn’t recommend doing it without a torque wrench. Presumably they’re not supposed to be very tight. Since they are pinching plastic against metal you don’t want to damage the plastic. But you don’t want them to fall out either. All mine were similar tightness (very loose) and one was missing so I concluded they should be very slightly tighter.

 

[schrodarkian]

Same issue here on my Model 3 AWD. The bolt missing was under the driver's side. The other bolts were very loose and looked they hadn't even been completely tightened. Unfortunately I found out during the first snow of the year and my car scooped up a bunch of snow/slush/gravel and I only noticed when I saw a lot of water under the car in the garage. Once I looked underneath I saw the cover was loose and had been scraped up (though I never heard scraping while driving).

I tightened all the bolts and temporarily borrowed one of the bolts from the middle so at least the side wouldn't be hanging down and scraping more. Hopefully this didn't damage anything under the cover!

Full disclosure: love the Model 3 (and our S), am long TSLA, but sometimes it can be challenging being an early adopter. Kinda feels like when I bought the first iPhone back in, what, 2007?

 

[AlanSubie4Life]

Seems about right. Seems like Tesla should be tightening these bolts. It’s very odd.

In the meantime, unfortunately all owners should check them. Front and rear covers, and also the rear bumper bolts.

Also, modifying above info, there is another thread focused specifically on the rear cover:

Ripped Undercarriage Composite from the rain?

I say in my above post there are 6 bolts for the rear cover, but that is incorrect, further investigation showed there are actually 13 total bolts; one in the middle, and 6 on the front edge, 6 on the rear edge. And there are various other attachments.

 

[Zoglog]

Is this limited to P3D+ Models?

 

[AlanSubie4Life]

Is this limited to P3D+ Models?

Applies to all Model 3 vehicles as far as I know. Certainly all AWD vehicles.

Probably RWD front covers are the same.

The front and rear covers are thought to be mostly for aero, and possibly to help keep some filth and moisture out of the motor area as well

 

[Velizar]

I took delivery of my P3D on 9/28 and I love my car but I had absolutely the same issue.

On Friday, November 2nd I took my first trip outside of San Antonio with my new Tesla 3, I had a business trip to Houston. On the morning of November 3rd I drove about 30-40 miles to University of Houston where my business was held from the place I was staying. Around noon same day I was on my way to lunch and when I got in my car there was a warning on the screen (attached). I did not noticed any changes to my steering wheel so I continued with my trip as I had only an hour for my lunch. After lunch on my way back to University the warning was not on screen. However, when I started driving and on the Hwy I started to hear a flapping noise like something was attached or loose to my front or underneath the car. At first I thought it was coming from a vehicle next to me but there was no one next to me driving. I stopped within a couple of minutes as I had to exit the Hwy., looked around underneath car and did not see anything that could create that noise. The only thing I noticed by looking from the front of the car underneath, it looks like the cover plate was not flush. As I never looked underneath my car before and did not know any different I didn't see this as a problem. Got back in the car and continued driving as I had just couple of miles left. Parked the car and called Tesla, I explained what happened as well as the warning I got, the person helped and we did some resets and he told me that he don't see anything wrong but helped me to schedule an appointment for Monday 5th in the morning with San Antonio Tesla center so they can check everything and also look again some other issues I had like connectivity. That same evening I left around 8pm and on my way I start to hear same flapping noise for a little while and than it stopped. As I was getting closer to my location and slowing down to about 10-20 miles per hour I started to hear some dragging noise, I opened my window and was able to hear it better. I stopped immediately to see what was dragging underneath and that's where I saw underneath cover plate between front wheels it was torn and dragging on the road as well as saw some liquid dripping. Now, I know for sure I did not hit anything on the road and I did not even go through any speed bumps that day or even the day before. I called immediately Tesla for help and we decided that best it will be to tow the car to Tesla on Westchase Dr. I stayed an extra day in Houston so to go Monday morning and see what had happen and what they can do so I can go back to San Antonio that day. They told be that something damaged plate underneath and punched a hole to some type of filter where the oil started leaking. They quoted me that cost for repair will be around $380. I told them that I did not run over anything and more likely this was caused by plate got loose as it now explains all the rattling noise I had earlier that day and it should be covered by car warranty as well as the towing coast. They argued this and I told them this will be fine as I needed to get back to San Antonio asap and I will write to Tesla thereafter and explain situation as I believe there was some kind of defect or loose part to cause all this, I know I did not run over anything!!! I asked if I can take some photos of my car underneath as it was on the lift (attached). There was not any evidence of me hitting anything on the road to cause all that damage and you can see in the photos. They told me that car would more likely be ready by end of the day which was excellent for me, they also provided me with a loaner for that day and I was very thankful. Around 5pm I got a phone call and was told that my car should be ready little after 6pm and they will stay few minutes extra for me to make sure they finish the job so I can be on my way back to San Antonio. I got there, got the car, left my credit card info so they can charge next day as they couldn't do it after 6pm and I was OK with it, they told me I will get receipt with email. I got an email on Tuesday with invoice attached from Tesla and everything was with zeros but I also did not see in the service done for the damage happened in Houston so I don't know why but than after all they may have realized that this should be covered with car warranty. However, Tuesday evening at 5:40pm I got an alert from my credit card that I have been charged $836.32 from Tesla, now this was a big shock for me as I know the repair was quoted less than $400 as well as I believe it should be covered by car warranty!!!

Now please take a look on the photos and see if there are any damages around the damaged filter or anywhere else underneath. Filter is high and there are many other aluminum edges from what I believe is car front motor sitting lower than that filter. How can filter get damaged and nothing around that sits lower if I had run over something? This should tell what happened, cover got lose by some kind of defect or was not put correctly in first place when car was made. All rattling noise I had was that plate was flipping from turbulence while driving on Hwy and when finally got destroyed from dragging and that filter was exposed to all rocks and debris on Hwy.

I took car to San Antonio Tesla service center and was told there is no evidence of me running over anything and it should be covered by car warranty. I'm very desalinated from Houston Tesla service center as they were not honest. I'm trying to get the attention and get this resolved by Tesla Customer Service but so far they are not cooperating so I may seek help outside Tesla.

 

[AlanSubie4Life]

Looks like your undercover got loose. It’s stiff enough that if things went just right I think it could dent and puncture the oil filter on the front motor (looks like that is the issue).

Whether an object on the road hit the aero cover and simultaneously damaged the undercover and filter, or whether the undercover bending back under the car damaged the filter when it got pushed into it, we will never know.

Filters are extremely fragile; they are made of thin metal that can be crushed by a strong hand. So not surprising that it got damaged and nothing else did, but a bit of a fluke. A good reason to have the aero cover to deflect most road debris!

I think if San Antonio service center is amenable to not charging you I would work with them to modify the charges so that it is covered by warranty.

 

[wokuku]

So does anyone know the torque spec on the bolts? I think I am going to proactively put on some blue threadlock and torque them

 

[AlanSubie4Life]

So does anyone know the torque spec on the bolts? I think I am going to proactively put on some blue threadlock and torque them

I did 36 in-lbs, maybe a little more, but was basically guessing. It can be a little tighter. I have tightened enough bolts that I am comfortable guessing if a torque spec can’t be obtained. Especially for a non-critical item like this.

In any case I have checked once or twice and they don’t seem to be loosening on their own. I suspect the washer provides enough force on the head of the bolt that the threads have some friction with the threads on the bolt hole, and maybe stops them from working free. But I am not a fastener physics professional! In any case, based on my experience, I don’t think threadlocker is really needed. If you drive a lot of dirt roads maybe check them after a few runs just to see...

 

[TheLocNar]

This has happened on every car I’ve owned. It’s annoying. If anyone has a model 3 or knows of anyone with one near Dayton Ohio, I know a guy who would like to work on a solution to this. Just shoot me a PM. He’d need to check out the car in person.

 

[Vitold]

Sounds like Tesla needs to replace few humans with robots for better quality.

 

[Glamisduner]

Having to check this at delivery is crazy, the car is too low to the ground to check this kind of thing. Plus when I went to pick mine up, I thought about looking under it, but didn't want to ay down on the dirty asphalt in a nice shirt.