Sticky, grimy coating under/near strut bar
 

Yesterday I detailed the engine compartment, but there was/is a very tenacious sticky, grimy brownish coating on the painted body surface beneath where the strut bar is secured to the body, which is pointed out by the blue arrows in the photos below. This coating is confined to only that area on the body. There is none of this on the engine or anywhere else.

The coating was so tenacious that I thought that it might have been intentionally sprayed on there by Nissan, but I plowed on and attempted to remove it.

It covered the entire area, but I managed to remove a good portion of it with some WD-40 on a soft cloth. The areas pointed out by the arrows are difficult to get at using that method and I wondered if a mild engine degreaser or something else might be appropriate.

Has anyone else had this coating on their vehicle and, if so, what did you use to remove it?

Thanks.

Does Canada require undercoating for corrosion protection? I know vehicles built for export to certain markets (Russia for example) have a very heavy wax applied to the underbody after they are built to help protect from heavy salt use and corrosive environments. If this is waxy, it could be over-spray of the protective wax.

The stuff around the electrical terminals of pic one look like something was blown on there. If BuckeyeZ' undercoating theory is wrong, I'd guess it's getting blown in there while you're running down the road (tryin' to loosen your load :) ).

Thanks, guys.

I take it from your responses that in the US this coating is not present on new vehicles. That is, all there is is just paint with no visible coating, right?

Now that you mention that it could be a wax, the consistency and feel do indeed resemble that of a wax. But this has got darker brown speckles in it which I suppose might be just dust that has attached itself to the wax. Maybe simply heating it with a hair dryer would cause it to melt and run right off.

You know, if I had it all to do over again, even though it was pretty ugly to my eye, I probably wouldn't attempt to remove it...... at least before investigating further what the heck it might be. So before going any further with cleaning, I'll take the vehicle to the dealership and see what they've got to say about the coating. I'll also take the opportunity to look under a new Z's hood to see if the same coating is present. If there is, not only will I not go any further on cleaning, I might actually be putting some more back on there! I like clean and pretty, but I also appreciate an ugly but protective coating.

Thanks again.

I do believe that may be some sort of aftermarket anti-rust coating/rust inhibitor, like the kind that the dealer sprays on your new vehicle in 5 minutes and charges you $599.99 for. I do not have any of it on my Canadian '16 Z.

Thanks for the info about your '16. This almost certainly means that the coating is not Nissan standard practice for Canadian Zs.

The interesting thing is that none of the cable-conduits that run over these areas appeared to have any coating on them when I started cleaning; which means to me that if anything was either deliberately sprayed on there, or accidentally got put on there for any other reason, it probably would have been done, or happened, before the cable conduit, strut or anything else close to the coated areas was installed.

In other words, if the stuff had been applied, or accidentally flown onto, those areas after complete assembly, those cable-conduits, etc. should/would also have been coated at the same time........ unless they were somehow, some way masked prior to application of the coating, which I suppose is possible. Maybe the tedious masking is the reason for the $599.99.

It could mean that the car has been repainted from a accident or something. The paint installer puts the coating on to seal the paint :stirthepot:

I have the same stuff in my engine bay. It's been there since day one. I have a 2011 Nismo, bought brand spanking new. I spoke with a mechanic a few years ago and he said the stuff served a purpose. I can't really remember but I think it was there to prevent corrosion. He advised that I leave it on there.

I think the greasy spots were more localized to the bolts on my engine bay. They may have used it a bit more liberally on yours.

Thanks!