Are you bothered by that ticking sound coming from the area under the hood? That could be the so-called lifter tick noise, which usually comes from the valve lifters. These components are the ones responsible for passing on the movement of the camshaft lobes to the pushrods. Such ticking sound can have various causes.
Causes of valve lifter tick
- Faulty lifter
- Dirty oil deposits
- Bent or deformed push rod
A lifter that has gone bad can generate ticking sound as it operates. When this happens, the solution would be to pull the lifter out and have it rebored. The task may be complex enough to be dealt with by an average DIYer, so it's best that you take your vehicle to a professional mechanic who can connect a diagnostic tool into the engine to pinpoint the bad lifter.
Among the causes of valve lifter tick that originates from the top half part of the engine, this is the easiest and cheapest to resolve as you simply need to change the engine oil to flush the oil deposits.
If you have the bad habit of pushing your vehicle hard and way beyond its limits or if you always treat the accelerator like that of the one in race cars, depressing it too much, it's more likely that the lifter tick is caused by a bent pushrod. The best solution for this trouble is push rod replacement.
Simple steps to solve valve lifter noise
Step 1: Check and adjust engine oil level, if necessary.
The engine shouldn't be too low on oil as it can cause the oil pump to ingest air at high RPM, therefore depriving the valve lifters of their much-needed pressure. If the level of oil is too high, on the other hand, the spinning crankshaft and rods will dash into it, creating air bubbles and driving them into the air. This can lead to the occurrence of meringue-like foam that isn't capable of delivering the right pressure.
If you notice that the engine oil is too high, you will need to drain the excess oil into the drain pan. If it's too low, you just have to refill it until you reach the appropriate amount of oil.
Step 2: Check for sufficient oil pressure and listen for valve lifter ticking or tapping.
You can do this by, first, adding an oil-flushing solvent into the engine and turning it on. Then, turn the throttle body's idle-adjustment screw clockwise to set the engine to idle at around 1,000 rpm for fifteen minutes.
Step 3: Pressurize and de-pressurize the lifters.
Position yourself on the driver's seat, slowly raise the throttle up to 2,500 rpm, and release it. Doing this again and again for around five minutes will pressurize and de-pressurize the lifters continuously, therefore delivering the solvent through and breaking the lifter plungers loose.
Step 4: Add lightweight engine-flushing oil.
Drain oil without removing the old oil filter and put in lightweight engine-flushing oil, which is usually 0W-20 weight, just a little bit thicker than water.
Step 5: Drain the lightweight oil, replace the oil filter, and add the recommended oil.
Let the engine idle for 20 minutes, repeating step three once in every three minutes. Drain the lightweight oil to the drain pan, take off the old filter from its place and replace it with a new one, and then add the manufacturer recommended oil. Start the engine again and listen for valve lifter ticking. If you still hear such noise, proceed to the next step.
Step 6: Check for bad lifters and/or bent pushrods.
Take the engine's valve covers off and inspect the pushrods for bent portion and the lifters for wear. Also check for worn-out or damaged rocker arms or valve springs. If there's a damaged component, have it replaced as soon as possible.