How to Replace or Clean the LPG Injectors of the Fiat Grande Punto

To clean the LPG injectors (located behind the front axle) on the Fiat Grande Punto, you need to perform this operation underneath the car, so obtain ramps to safely lift the vehicle. Start by removing the rail that contains the injectors.

First, disconnect the connectors by pressing the tab and pulling it out (make sure to take a photo to reassemble them correctly). Remove the side connector by first lifting the yellow safety tab and then pressing the tab to extract it. Remove the two 13mm screws that hold the rail bracket.

Remove the side pipe by leveraging to remove the clamp and then using a screwdriver to detach the pipe (be careful as gas may escape). Remove the two 10mm bolts where the pipes are and finally disconnect the pipes by leveraging to remove the clamps and pulling the pipes.

Before cleaning the injectors, check for current with a multimeter set to 200 ohms, inserting the probes into the connectors. If the value fluctuates between 0.12 and 0.14, the injector is good; otherwise, it needs to be replaced.

To remove the injectors for cleaning, take off the plate by unscrewing the four 10mm bolts, slide out the injectors using a small flat screwdriver from the side (being careful not to break/scratch the plastic or seals). Once each injector is removed, take off the seals (being careful not to break them, starting with the larger seal and then the smaller one) and remove the filter with a small flat screwdriver.

To clean the injector, immerse it in cleaning petrol, fill it with solution, and when it is full, you will see dirt coming out into the container (this operation should be done until no more dirt comes out and the liquid is clear; if the liquid is too dirty, discard it and repeat with clean liquid).

When you see clear liquid coming out, the injector is clean, and you can move on to the next injector until all four are clean.

After cleaning the injectors, tidy up, spray some grease on the clean seals, reassemble the injectors, orient the injector tabs downwards, insert the plate and tighten the four 10mm bolts, insert the side sensor by tightening the 10mm bolt, and perform the assembly in reverse order to disassembly, connecting the plugs, referring to the photo taken before disassembly to connect them correctly.

Once everything is reassembled, you can test the car. For a simple replacement, remove the four injectors and insert the new injectors and new seals.