- My model of MX-5 is: 1997 1.8 iS
- I’m based near: _ Ipswich
- I’m looking for technical help or recommendations on: I have noticed that my car has been building up this black soot on the exhaust and every time I wash it off I comes back faster then the last time and in a greater quantity.
I have noticed when I let off the throttle suddenly, it mostly happens between 3-4k , the revs jump up maybe 100-200 or so all by itself and the car has a bit of overrun and makes a few popping noises this is also happening between up shifts as well, and seems to be becoming more frequent and louder the more miles I do in the car.
While I do rather enjoy the sounds that are coming out the back I just thought I would ask as it is becoming more frequent and creating more and more black soot, so just wanted to see if anyone has had the same thing/know if this is an issue as it is becoming more prevalent the more miles I do.
Cheers 
