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An engine valve adjustment sets the small gap, called lash, between each valve and the part that pushes it open. Route 66 Auto Repair in Upland measures that gap on every valve with feeler gauges, records the readings, and resets any that drifted out of the factory range. Many engines with solid lifters or shim buckets need this on a mileage schedule. Our ASE-certified technicians write the as-found and as-left numbers on your repair order so you can see what changed.
What are the signs your valves need adjusting?
- A light, fast ticking from the top of the engine that follows engine speed
- Rough idle when cold that smooths out as the engine warms
- A misfire code on one cylinder with good plugs and coils
- Your maintenance schedule lists a lash check at the current mileage
Is a tight valve worse than a loose one?
Yes, usually. A loose valve makes noise, which is annoying but honest. A tight valve is quiet and does not fully close, so it cannot shed heat into the cylinder head. Over time the valve face and seat burn, and compression on that cylinder drops. That is why we measure every valve, not just the noisy ones.
If a reading is far out of range, we look for a reason before we reset it: a worn cam lobe, a collapsed lifter or a damaged seat. Those findings go to engine diagnostics first so you are not paying to adjust around a bigger problem.
Our valve adjustment process
Step 1: Cool-engine check
Lash specs are written for a cold engine, so we plan the job around a cool block.
Step 2: Remove the cover
We take off the valve cover and inspect the gasket, cam lobes and oil condition.
Step 3: Measure every valve
Each valve is rotated to its base circle and measured with feeler gauges.
Step 4: Reset and recheck
Out-of-range valves are set by screw or shim, then measured a second time.
Step 5: Seal and road test
A new cover gasket goes on, and we listen and road-test before release.
What's included in an engine valve adjustment
Included on the work order
- 01Lash measurement on every intake and exhaust valve
- 02As-found and as-left readings on the repair order
- 03Screw adjustment or shim change where the design calls for it
- 04Valve cover gasket and seals as listed on the estimate
- 05Visual check of cam lobes and rocker surfaces
- 06Idle quality check and road test
Is a valve adjustment a need-now or need-later repair?
Need now: call
- A misfire traced to a tight valve
- Loud ticking with power loss on the freeway
Need later: book
- A scheduled lash check with no symptoms
- Faint tick on a cold start that fades in a minute
How pricing and timing work
Price depends on how the engine is built. A screw-and-locknut design is quicker than one that needs shims swapped, and a V6 with a rear bank buried under the intake takes longer than an inline four. Your written estimate lists the gasket set and any shims before we start. AAA members get 10% off parts and labor, up to $75. Many adjustments are same-day when the board allows; call (909) 608-7699 before you drive over.
After your valve adjustment
Expect a quieter top end on the first drive. If ticking returns quickly, that points to wear, and a comeback goes to the front of the line.
Frequently asked questions
How often do valves need to be adjusted?
It depends on the engine. Many with hydraulic lifters never need it; others list a lash check at set mileage. Tell us the year and engine and we look up the schedule first.
Can a valve adjustment fix a misfire?
Sometimes. If one valve is too tight to seal, that cylinder loses compression and misfires. We confirm that with a compression or leak-down test before we promise that the adjustment alone will cure it.
Do you replace the valve cover gasket at the same time?
Usually, since old gaskets rarely reseal well. If yours is a reusable design in good shape, we skip the charge and the estimate says so.