jasone36

Hello,

I have a 2002 SC430 with 130K+ miles. I have noticed a metallic ticking type of noise from under the hood, seemingly on the right side of the engine around where the spark plugs are (if looking at the engine from the front, facing the car). I have noticed the sound seems to be worse when the cabin ventilation system is set to high (pushing a lot of air into the cabin).

The car only gets premium fuel, but I've only owned it for 4 months, so I'm not sure if this is "engine knocking".

Please let me know if you have any ideas as to the root cause of the issue.

mrblister

Take off the engine oil fill cap and see if the tick is louder . DONT race engine so you dont throw oil out . if its ticking could be a valve

Swishh

mrblister sounds right... probably just valves ticking. Have you ever had them adjusted? Sounds to be about that time with 130K miles. Make sure your oil level on the dipstick is full too.

bacardi

jasone
it sounds like a lifter tapping, if it has lifters and trying to adjust it i don't think will help. they tap when the lifter or lifters is going bad. if thats the case, you just can't put a lifter or lifters in. the cam and lifters need to be replaced. just replacing the lifters will cause the cam to go for sure.
gene

Poqman

I wouldn't rule out a fuel injector tapping. I would try a few tanks of fuel with an injector cleaner first. If it continues, then look to a lifter.

toxic

Too many things it could be. Don't forget a cracked manifold as well.

TOXIC

jasone36

I've been reading other ClubLexus forums and it seems this is a very common thing in the GS and IS of similar years (2002-era), the folks on the other forums are saying it's "normal".. I wonder if this applies to the SC430 also.

braheem

iTrader: (4)

There is no is430 you sure it was a gs430 in the gs forums?

jasone36

The GS430 forums report the same issue, and yes there is no IS430 but the IS folks seem to have similar sound with their 3.0 liter enginges. I figure many of the components are shared between the platforms,

braheem

iTrader: (4)

Cut a garden hose to about 4 feet and use it as a stethoscope, you'll pinpoint EXACTLY where it is.

Harold57

Or use a screwdriver long enough to place against parts of the engine and your ear to the other end. OTOH, you could just go buy a mechanics stethoscope from Harbor Freight or someplace like that. They are fairly cheap.

jasone36

For an update on this item, it appears my evap house was disonnected under the hood, which likely added to the metallic clicking sound I started hearing around the same time I started to smell gas in the cabin (when the air vents were set to pull in air from the outside).

Please see my related thread below. I feel the items are connected.

https://www.clublexus.com/forums/sc-...ml#post7028467

bacardi

nice, i know you don't need theses problems.

jasone36

bacardi, I could not agree with you more