Ceramic coating failures almost always come down to one of two things: application errors, or surface prep that wasn't thorough enough. In my experience, surface prep accounts for the majority of early failures — coatings that don't bond properly, peel in sections, or lose their hydrophobic properties within a few months instead of lasting years.
The good news is that proper decontamination isn't complicated. You just have to do the steps in the right order and not skip any of them.
Step 1: Wash thoroughly
Start with a foam pre-soak if you have a foam cannon, then a full two-bucket hand wash. The goal is to remove all loose dirt, road grime, and surface contamination before anything else. Don't use a car shampoo with wax or shine additives at this stage — you want a pure cleaning shampoo that leaves nothing behind. Rinse completely and dry the car before moving on.
Step 2: Iron decontamination
This is the step most home detailers skip, and it's a critical one. Iron contamination — brake dust particles and industrial fallout that have embedded themselves into the clear coat — cannot be washed off. It has to be chemically dissolved. An iron remover spray causes a color-change reaction (turning purple) where iron deposits are present, giving you a visual indicator of how contaminated the paint actually is.
Apply the iron remover to a cool, wet panel, let it dwell for 3–5 minutes, and rinse thoroughly. A heavily contaminated car may benefit from two applications. Don't let it dry on the paint. We carry iron decontamination products including GTECHNIQ W6 FALLOUT & IRON REMOVER, which has a gel formula that clings to vertical panels better than standard spray formulas.
Step 3: Tar and adhesive removal
After iron decontamination, check the lower panels and rocker areas for tar spots — small black dots that didn't come off in the wash. These need a dedicated tar remover (not iron remover — they're different chemicals for different contaminants). Apply to a microfiber, work in small sections, and wipe away. Tar spots are common on cars that drive highway miles regularly and are especially prevalent in summer when road asphalt softens.
Step 4: Clay bar or decontamination pad
Even after thorough chemical decontamination, there will be physical contamination bonded to the surface — silica particles, industrial fallout, paint overspray — that chemicals alone won't remove. Running your fingertips across a freshly washed panel and feeling any roughness is contamination that needs clay or a synthetic decontamination pad.
Use clay bar lubricant generously and work in small sections with light pressure. The clay will pick up the contamination and the panel should feel glass-smooth afterward. After claying, do a final rinse and dry.
Step 5: Paint correction (if needed)
If the paint has swirl marks, scratches, or water spots you want to remove before coating, this is when to do it — after decontamination and before coating application. A ceramic coating locks in whatever the paint looks like at application time. Correcting after the coating means stripping it and starting over. If you want clean paint under the coating, correct it now with a machine polisher and appropriate compound and polish. If the paint is already in good shape, skip to the next step.
Step 6: IPA wipe-down
The final step before coating application is an isopropyl alcohol (IPA) wipe-down, typically a 50/50 mix of IPA and distilled water. This removes any residual polish oils, clay lubricant residue, or silicone contamination from the clay process. It leaves the surface completely bare — no protection whatsoever — which is exactly what you want right before coating application. Work panel by panel and coat immediately after wiping, ideally in a garage out of direct sunlight.
Why the order matters
Each step builds on the previous one. You can't clay a contaminated panel effectively — the clay will load up with loose dirt before it gets to the bonded contamination. You can't IPA wipe before claying — the lube residue will interfere. You can't correct paint that still has iron contamination embedded in it without accelerating compound and pad wear. The sequence is the system.
Skip a step and you're essentially coating over a problem. Do all six steps in the right order and the coating has the clean, bare surface it needs to bond properly and perform as advertised. If you want to prep your full kit, check out our ceramic coating products and decontamination supplies — everything you need for a proper prep is in those two collections.