Honda Fit L15A7 Valve Clearance Check and Adjustment (2nd-Gen GE8)

Work only on a fully cold engine: leave the car unrun for six to eight hours so everything sits at ambient temperature, because warm components read out of spec. Park on level ground and make sure a second vehicle is available, since the Fit will be undrivable through the whole job. Before removing anything, steer the front wheels fully to the right by hand with the engine off. This lines up an access opening in the wheel well on the passenger side, giving you later access to the crank pulley bolt so the engine can be turned over without pulling the road wheel.

Open the hood. Release the retaining clips and the MAF sensor connector, then lift out the air filter housing and its element. With a 10mm socket, disconnect the battery terminals and the hold-down bracket - the bracket's hooks slide out from beneath the battery base, so it need not be fully unbolted. Lift out the battery, then remove the battery tray and bracket to open up working room above the engine.

Loosen - but do not fully unscrew - the clamp holding the remaining intake tube to the throttle body; a molded stop prevents the tube from sliding rearward. Remove the two 10mm bolts that secure the airbox bracket to the block and gearbox, then release the green wire clip. Ease the assembly off the throttle body. Use pliers to work the metal vacuum tube off its rubber grommet, relieving pressure rather than yanking it, then set the airbox aside.

Undo the four 12mm bolts securing the throttle body, taking care to keep the metal brackets on its front and rear faces. Disconnect the two electrical connectors. Swing the throttle body clear of the intake path; you can leave its lines attached and simply support it out of the way.

Take out the five 12mm bolts joining the plastic intake plenum to the metal manifold and remove the metal bracket behind it. Remove the two 10mm bolts located behind the plenum, then the final 12mm bolt on its side. Detach the vacuum line at the valve cover and unclip the hose running to the back of the plenum from its bracket - that hose can stay attached to the plenum while you lay the assembly aside.

On the second-generation Fit the valve cover tucks under the windshield cowl, and clearance is too tight to measure and adjust accurately with the cowl in place. Remove the wiper arms, the wiper motor and linkage, and the plastic cowl panel - it is a designed service-removable part and comes off in a few minutes once the wipers are clear. Keep spare cowl clips on hand, as the originals can break. Working with the cowl still fitted is possible but makes the rear valves considerably harder to reach.

Unplug each ignition coil connector, release the wiring bracket on the left side, and move the harness out of the way. Remove the eight 10mm bolts around the perimeter of the valve cover and lift it off. Go gently - more than one owner has snapped a valve cover bolt here, so if one feels seized, stop and free it rather than forcing it. Set the cover and its gasket somewhere clean for inspection and resealing later.

Fit the 19mm socket on an extension through the wheel-well access hole and turn the crank clockwise only - never in reverse. Watch the cam gear: a cylinder is ready to measure when its number sits at the twelve-o'clock position and the scribe line on the cam gear hub is level and flush with the top edge of the cylinder head. Bring each cylinder to top dead center in the firing sequence 1-3-4-2, rotating the crank between cylinders. At TDC for a given cylinder, both its intake and exhaust valves are closed and can be measured.

With the cylinder at TDC, slide the correct feeler gauge between each cam lobe and its follower. A correct clearance gives light drag and a faint vibration as you draw the blade back and forth - neither free-sliding nor pinched. Do not flex the blade, which falsifies the reading; bent-tip (offset) gauges make the tight spaces far easier. Cold specification is Intake 0.15-0.19 mm (0.006-0.007 in) and Exhaust 0.26-0.30 mm (0.010-0.012 in). In practice the exhaust valves are the ones most often found tight. Record every valve before touching an adjuster.

For any valve outside spec, loosen the locknut with a 10mm open-end wrench and turn the adjuster screw with a flathead screwdriver. Set the gap with the target feeler blade in place: snug the screw down until the blade can just barely no longer be pulled free under light force, keeping the blade moving so it does not bind. This part is critical - tightening the locknut lifts the adjuster and opens the gap slightly, so hold the screw dead still with the screwdriver while you torque the locknut, then re-measure. A jam-nut valve adjustment tool (for example the Alltrade 648827 10mm) makes holding the screw while locking the nut much easier. Many owners aim for the loose end of the exhaust range and use a go/no-go check - one thousandth over the target is no-go, one under is go.

Once every cylinder is verified, reassemble in reverse order. Scrape and clean the valve cover and head sealing surfaces so the gasket seats cleanly; reuse the gasket if it is intact, or fit a new one (Honda 12341-RB0-003). Apply a dab of Hondabond or equivalent sealant to the cam-cap seams at the front and rear of the head before lowering the cover. Reinstall the eight cover bolts snugly without over-tightening, then refit the coils, intake manifold, throttle body, airbox, battery, and cowl. If you pulled the spark plugs while in here, torque them to 20 lb-ft. A slightly louder tick afterward is normal for this solid-lifter engine, especially with the exhausts set toward the loose end of spec.