Destroy eco grid with Jinx was a mission in Jak 3. Torn called Jak over the communicator saying they found four critical power junctions (the eco grid), which if destroyed, could drop some of the shields in the Industrial Section. He sent Jinx to take care of these, but in turn needed Jak to guard Jinx from the enemies.
Jinx is waiting outside the Southern Haven Forest in a two-seated zoomer (if destroyed, you can pick up a new one). Hop in and race out of there as cloakers will be shooting at you. When you get to the first target, park the car nearby Jinx so you can get away quickly. Grunts and stingers will come at you (from the Port direction actually), which are all easily defeated by the Beam Reflexor. Normally, the Wave Concussor would be a good choice too, but it has a tendency to blow away your vehicle. The Gyro Burster is good too, but the ammo cost is rather high. The next one is pretty much the same as the first
Once in the Industrial Section, you will be attacked by spydroids, sentinels, and the most dangerous, roboguards. Using the Arc Wielder (with robot shock) is a good choice here, but both the reflexor and the burster are useful to keep the roboguards down. As with the first two targets, the last two are also pretty equal in terms of what's coming at you.