Hey guys,

Recently started hearing a ticking noise coming from either the engine or the exhaust. Cant rly seem to find the source of the noise. I started using mobil 1 hile mileage full synthetic 5w-30. That was the last oil change, could this type of oil be bad for the engine? Today i changed the serpentine belts+ pulleys and replaced the spark plugs. I'm thinking about changing the oil+ filter, maybe a non high mileage oil? Do you guys have an ideas of what it could be? Video of the sound below.

 

I would definitely switch back to some kind of conventional oil if the sound started after using synth. Conventional oil is a larger molecule and typically runs at a higher oil pressure than synthetics on this engine, since your engine has some wear and tear associated with it I would give it the oil it was designed for to ensure proper oil retention around the bearings.

 

Hey.

Thx for the reply. I've been using synthetic oil. For the last oil change I switched to high mileage synthetic. Not sure if this new oil triggered the ticking. Gonna try switching back to just a regular synthetic. Maybe it will make a difference.

 

OP I'm really sorry to tell you this but oil won't help you at this point. What you are hearing is rod knock, it has a very distinctive sound. Your motor is getting closer to throwing a rod every time you run it and it's toast at this point. It might be cheaper to source a used engine but you're going to have to rebuild yours or replace it.

 

Ouch that sucks...do you know if its a rod knock or a lifter tick? Gonna have to get it fixed, replacing isn't an option right now.

 

That doesn't sound like lifter tick at all, I would get it up on a lift/jacks and probe around with a mechanics stethoscope. Best case scenario it's the timing chain guides are toast and the noise is actually coming from the timing chain cover (easily mistaken for rod knock on this motor), worse case the bearings are shot and the noise is coming from the oil pan region.

It does sound like rod knock unfortunately but get it properly diagnosed before sending that motor off to the graveyard.

Edit: Words are hard...

 

Cleric I've had 2 friends that lost a G motor to rod knock and it sounded exactly like his motor does.

OP good luck, I'll be keeping my fingers crossed it's not something serious but definitely keep us posted.

 

Yeah that was a Google Voice typo and I didn't proofread, should say...

It DOES sound like rod knock unfortunately...

 

thats a rod knock friend, my condolences

 

Agreed, sounds much more than just tensioners or chain. Something in the bottom end for sure.

 

That's a rod knock! There is no "Fix" just replacement! Start searching the right coast for a low mileage VQ motor to replace yours, time is "ticking away!" (sorry!)
Gary

 

I lost my 04 coupe 6MT to this very same issue a few years ago! At least I salvaged a little bit of it by selling it "as is" to a mechanic student for $3k.
Why is this such a problem on these overpriced cars?

 

lol overpriced really? We've got people buying 04's with 130K miles for $4000 so I'm not sure what your definition of expensive. Most rod knock issues come from improper maintenance of the engine such as regular oil changes.....

 

Pay $43k for it brand new, maintain it regularly, buy expensive tires, replace expensive clutch at 140k miles, etc, and it can't even make it to 200k miles...
A guy out there certainly did pay only $3k for a 04 with 160k on it - mine, but the engine was shot. That's a huge loss for me. These cars are biting the dust prematurely all the time. Just look at this thread and countless others. The guy that paid a few grand for a used one and got a few good years out of it - not a big deal. But a guy having less than 7% resale value after 10 years is not going to feel the same way.

 

.Pay over 100k for a Benz only for it to lose 95% of its value in 10 years.People eat much more depreciation with other brands, at least our parts prices are reasonable, factor in expensive parts like coil packs ($1k) and suspension components, suddenly the G35 looks rather reasonable. Furthermore, it helps to open to the hood every once in a while beyond regular maintenance . My 03 just did a 470 mile trip one one tank of gas with 132k miles on it. My cousin has 180k on his 06X sedan that he beats on relentlessly around Brooklyn NY and its been as solid as anything.