Here is the deal.
After many years vinyl will start to break down on it's own.
Using the wrong cleaners or protectors will accelerate the process. Over time, the plasticizers in vinyl leach to the surface and I suspect that there was some interaction with a cleaner or polish.
The fix!
TAC Free, a SEM product, sold on Amazon.
You can buy one of there prep/cleaners or just use alcohol. Then spray TAC Free on it an no more tacky
Good tip, ordered some today to try on our seats. Thanks
Wonder if that would work on the ceiling?
Amazon.com: SEM 39643 Tac Free Aerosol - 12 oz. : Automotive (https://www.amazon.com/SEM-39643-Tac-Free-Aerosol/dp/B008QDEXYC/ref=sr_1_1?crid=3GMFMWI1TQOGE&keywords=tac+free&qid=1704040535&sprefix=TAC+Free%2C%2Caps%2C153&sr=8-1)
I used this on ours since acquisition. Does a great job of cleaning, removing that sticky feel, and making any Vinyl surface look like new. Seats, trim, ceiling....any surface that is vinyl/Naugahyde/pleather...use it straight out of the bottle, but do wear gloves, prolonged skin contact does dry out your skin. I put some in a bowl, keep a rag wet with it and just wipe away, then use a towel to wipe it dry. Overly sticky areas a bit of light rubbing helps.
Amazon.com: Malco Clean & Shine Interior Car Cleaner and Dressing – Restore... (https://www.amazon.com/gp/aw/d/B0742PGNYB/?_encoding=UTF8&pd_rd_plhdr=t&aaxitk=c1fa40cf802806abe00fe11cec832426&hsa_cr_id=7313810120101&qid=1704167899&sr=1-3-9e67e56a-6f64-441f-a281-df67fc737124&ref_=sbx_be_s_sparkle_mcd_asin_2_title&pd_rd_w=vaKZi&content-id=amzn1.sym.417820b0-80f2-4084-adb3-fb612550f30b%3Aamzn1.sym.417820b0-80f2-4084-adb3-fb612550f30b&pf_rd_p=417820b0-80f2-4084-adb3-fb612550f30b&pf_rd_r=06GE3YBWDCG14AMDGBAX&pd_rd_wg=ww8Zn&pd_rd_r=68d88c93-4607-4b61-ae71-49321cb332e2&th=1)
FYI, for those with newer coaches or who have had seats replaced or recovered, if the material is Ultraleather the recommended cleaner is soap and water, and alcohol-based cleaners 409 or Fantastic for heavier soil. You do not want to use vinyl cleaner or any form of conditioner or dressing on Ultraleather (in particular if it's the Brisa line, which has micro perforations to make it more breathable.
I have no idea what the entire inside of our 2001's version of plastic leather is called.....But I do know that the recommendations for Ultraleather made the stickiness worse, I tried that first based on recommendations here.
The entire inside of our coaches vinyl when we acquired it was as though children had smeared candy or jelly on every inch of it, and was only wiped off with water......spotless in appearance yes, but every inch of it very sticky, almost like touching weak duct tape.....as someone that has restored classic cars for over 40 years, I have only experienced similar with vinyl interiors that were neglected or abused. But our coach in no way appeared abused or neglected....I I have a cabinet full of auto detailing cleaners/solvents/waxes/etc....Trying the recommended first, then trialing all others I had....the only other that somewhat had positive results with the stickiness was Simple green, and though an ok smell, preferred not to use it for that reason.....I had an old bottle of Malco cleaner and gave it a try. The results were great and almost 3 years later, that feel has not returned.
Regardless what you use, trial it on a hidden spot first. Make sure it does not affect color fastness....Aside from solvents (which I dont recommend), I have never seen a cleaner that would remove color from Vinyl.
I have used SEM vinyl dyes for decades, great stuff and holds up under excessive southern heat. But the SEM TAC FREE is a TOP coating to be used over freshly dyed vinyls to keep that sticky from ever happening....If it just so happens to work over sticky worn out dashes that is great, but the plastic or vinyl should be properly cleaned first, which in the case of plasticizer migration ( plastic additive UV stabilizer failure) is not possible. Not to include is an aerosol. I am not sure I would want to spray my entire interior with something that is going to get all over everything.
for what it's worth, I worked for the chemical plastics industry for 36 years. 10 of those years in QA lab testing.
I used Krud Kutter on our ceiling took dirt and stickiness off.
Excellent work out for the shoulders.