I wouldn't recommend using it on a high mileage car that hasn't been treated before. It can dislodge buildup which can then accumulate in the cat and cause premature failure.
Otherwise it's a great product when used correctly. It's a petroleum based solvent so try not to use more than every 10K or so.
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09 CWP MS3
01 Echo 5MT
00 EBP Si - Sold -
Pics89 Camaro - Sold
CSI. What's your diversion?