White stain mystery

Technical Area Cleaning & Detailing
1
  1. My model of MX-5 is: ‘07 NC, 1.8L
  2. I’m based near: Oxford
  3. I’m looking for technical help or recommendations on: White marks on paint

So I’ve had a couple of separate incidents getting white stains specifically on the front bumper of my MX5.

Today was by far the worst, as the citrus pre-wash I used (Yum Cars) left behind some major stains despite covering with snow foam and rinsing off pretty quickly - I guess not quick enough….

The bizarre thing is the issue is ONLY present on the front bumper - I applied the same chemical and process to the rest of the car without issue.

Some fairly intense polishing has helped mostly remove the stains - can only see them up very close now - but it’s not an especially fun and rather frightening process! To top it off my polish pad is showing some red, so presumably I’m starting to eat away at the paint now…

Considering this is the second time with two different problem products, I’m assuming there’s something up with the bumper paint job - presumably it’s been resprayed at some point, maybe with single stage (hence the red on the polish pad)?

Would love to know if anyone’s seen anything like this, or has some thoughts / advice?

Here are some pics of the issue before polishing:

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image4032×3024 2.2 MB

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image3024×4032 1.68 MB

2

These Citrus Pre-Wash products can cause a problem on plastic painted parts, which is why I have not used them.
Did you dilute it correctly or was it ready mixed?
Was your rear bumper stained at all?

3

Have a look here.

It may be the same problem.

David

4

So it was pre-concentrated - and there are no marks on the rear bumper at all, despite laying it on there too.

So I’m thinking this front bumper has a different, maybe single stage, paint job…

5

I’d say the front bumper had a respray at some time. As it’s base red with no lacquer i’d bin the Citrus pre wash. . As for snow foam never used it.

6

Agreed that the bumper has more than likely been resprayed and in all honesty, I think you’ll have to consider another, better respray at some stage.

7

I would suggest it’s had a poor-quality re-spray at sometime and the cure for the problem will ultimately be a better quality respray.