2005 G35 AT Sedan with 105k. I bought it a few months ago from Infiniti. A week into owning it, I started getting a misfire/engine hesitation. I brought it back to the dealer and they said my oil was just low. I owned an 03 G before so I know G's have oil consumption issues so I didn't think it was a big deal.

They changed it and used a synthetic oil blend and OEM filter. Car ran fine with no problems so I decided to keep it instead of trying to return it.

Car drove fine for 4 months but about 2 weeks ago, I noticed my car was running a little rough. Definitely not as bad as before when misfiring, just a little shaky at idle and shaky when I left off the gas to slow down at a light (kind of like a slightly warped rotor). I only put 1,800 miles on it since the last oil change.

I checked the oil and it was more than full still. I decided to change it hoping that would fix things. I put regular 5W-30 Pennzoil and a Fram tough guard filter. The car stopped idling rough BUT now, I'm getting this knocking/ticking sound.

It's not super loud as you can hear and only heard when outside the car. It only starts knocking after the engine has been warmed up and driven for at least 15 minutes. The knocking only happens in park or when above 1,000 RPMs, it's silent when I'm in gear and stopped. When I rev, the knocking gets faster but not louder. Since revving makes the engine louder, I can't tell if the knocking sound stops after going above 2k RPMs or I just can't hear it anymore. I also can't really tell where the sound is coming from. It seems like it's from the engine bay though and not near the cat or pipes.

I use 91 or higher gas at all times. It only had one prior owner and it was well maintained. The oil has remained full and I check it regularly since I changed it. No loss of power.

I searched the forum and YouTube and couldn't find someone with the same exact symptoms, something was always different. Most of the stuff on the forums point to leaking valve covers, lifters, bearings, or oil in spark plug issues. A lot of people had the knocking on startup issue but that's not the case here. I really hope it's nothing internal or the cam shafts. I still have the old oil so maybe I can check for some metal.

Also as you can see at 0:16, I zoomed in on the left side of the engine and I see some oil grime. Not sure if that was there when I bought it or if something is leaking. What does that look like to you guys?

Where do you guys think I should start first? I go to work/school full time so I don't have much time to work on it. I may just bring it to a mechanic to have it checked out but I'd like to give him some ideas on what it could be also. Any advice to save me some time is appreciated. Thanks.

Video:
Help with Infiniti G35 VQ35 Engine Knock Ticking

http://m.youtube.com/?reload=2&rdm=13zbj09n#/watch?v=eiaUtEtNwH0

 

they sell stethoscopes like doctors used for mechanics. That is usually how a mechanic will pinpoint a noise if they don't know right off hand.

Your front timing cover is leaking pretty bad. Provided that noise in noting major, to fix that oil leak, you have to remove all the accessories off the front of the engine and removed the front timing cover. While you are in there, considering your mileage, you should replaced the chain, tensioner, guides, water pump, and thermostat. That's if you want the job done right.

I think most shops would charge 6-7 hours for that job so you could be looking close to 1k by the time your out of their.

For another $500, you can pick up a low mileage motor from the junkyard and about 1-2k to have it installed. My point is, maybe you should just run the engine as is and save up for a new engine. Your engine would probably go for a long time as is.

My only concern is that the dealer didn't pull a fast one on you. I would remove the top engine cover and see if any protruding gasket between the timing cover looks relatively new. Maybe they took a bad car in on trader and fixed it up real quick. I'm not sure how likely that is though.

 

sounds like rod knock...typical for engines that use Fram filters which are made with cardboard valves that allow empyting of filter after shut off allowing DRY START causing rod inserts to wear causing to much clearance. the damage is done...you could try heavier oil such as 20w40 for the thicker viscosity. for starters get that FRAM OUTTA THERE

 

Your timing chain cover is leaking ( the oil grime youre referring to in your post is the valve cover though).
Next time dont change your oil at 1,800miles as thats not the right solution in your case.

If I were you I would have taken it to the place you bought it and talk to them.
Your engine does seem quieter than mine.
Try this combo out next time you change your oil :
German castrol 0w-30 and Mobil 1, Bosch, K and N, Purolator oil filter it might help quieten down the ticking youre hearing.
If its lifters then you might want to use Seafoam in the crankcase/vacuum line before the next oil change.

 

Thanks for the advice guys.

As for the Fram filter issue- I previously had an 03 G and always used Fram & Mobil 1 and never had an issue. I always thought Fram was a solid brand but after this, I'll probably go with something else in the future.

After considering the fact that engine work was going to be needed regardless, I just decided to get rid of it. I paid $8000 for it when I bought it and dealer gave me $6500 on trade in so it wasn't a total loss since I would've probably had to pay that much in repairs. I ended up getting a 2012 Accord Coupe WITH a lifetime powertrain warranty so I'll never have to worry about engine problems again! Haha

I also did consider bringing it back to the dealer but in the end, it just wasn't worth it. A few months into owning it my drivers seat and CD player also stopped working. The car also had some paint fade that I planned on fixing (that's why I bought it so cheap). I would've just been wasting my money with a car that I wouldn't have been happy with in the end.

Ah well, I think I'm done with Infiniti at this point. My old G also had the driver seat and CD player issues. I love my Japanese cars but Infiniti has lost my trust. Goodbye forever.

 

You cannot blame the brand for the problems. You have no idea how the previous owner drove the car or if the car was as well takrn care of as you think. My car has 188k on it and I drive it hard. No problems here, but I have owned it since new. I dont buy used because sometimes you are buying someone elses problems. Your money so do as you like, but dont condemn the brand for bad experiences with used high mileage cars.