[RedDevil]

Welcome.

You make me wonder what car(s) you're going to subject to your DIY emissions test, and what you will do to improve on them.
For my bikes I did simple things like just smell the exhaust gas, observe the caking on the spark plugs and the like. When in doubt it was dealership time. My cars always ran fine so I never felt the need to test, and with modern cars with ECU's and 3-way cat systems there remains little to test I fear.
On my car I'd expect no gain from this kind of testing, while raising the tire pressure somewhat and installing HIDs and LEDs are surefire ways to get better mpg.

But I agree, I ecomod as a hobby so I have to like what I do. I will make mods that won't pay for themselves if I feel like it, and leave those which would but I don't fancy.
Improving on emissions works for the environment too, not just the wallet. That's eco²modding

My daughter has not yet mastered her walk-bike, and my 5-year old son, who reads, writes, does basic math and studies Japanese tokens and the Greek alphabet (ancient, modern and archaic), is still in his diapers - a true-to-form Asperger... but one day he'll be a mean ecomodder