Recently acquired an 03 g35. Went on a test drive before trade was done. Had slight knock, tapping noise, from what seemed to be passenger side head area. Car ran fine noise climbed with Rpms but got quiet around 2k rpms. on the way home with the car pushed the car slightly from 75 to 120 mph only boosted 8-10 psi and short burst. Slowed down to take a turn and car died betting fouled the plugs with oil that was now pouring out of exhaust. pulled turbo cold side pipes and checked for oil. passenger side was coated driver side dry added oil. Started but no oil coming out of turbo area. Any ideas to check before I pull the whole engine and find something simple

 

I hope you got this car for a steal...engine rebuild and turbo rebuild in your future...I wouldnt even worry about an absence of oil after your startup - just start dismantling the car.

 

That's what I'm planning on anyways was just curious if there may be something external leaking that I haven't seen knock I'm thinking is possibly head gasket or broken valve spring. Going to do compression test before I pull it out anyways

 

Have you talked to the seller? Got some pictures, videos of that sound? the tapping could be the fuel regulator sometimes taps.

 

A boost leak test is a neat trick for more than just IC piping and the intercooler. I have used this test and found bent valves and even a blown head gasket on occasion. Try it out but do so away from the compressor or any loud shop equipment so you can actually look, listen, and feel for escaping air.

 

if oil was coming out your exhaust, your turbo took a ****.

 

I got it in the garage and other than an air compressor it's the only noisy thing in there. But curious how was you able to check for a blown head gasket? I've never checked them that way before usually only with a compression gauge.

 

That's what I was thinking but hoping not lol wanting it to be head gasket or valve seal failure. When it went it started missing real bad but I haven't figured out how to pull codes from the unichip... See if that would give me an idea

 

I wouldn't have thought of that. But it shouldn't be a constant sound should it? I thought they were usually not loud enough to be heard sitting in the car

 

I'll take a video of it tomorrow before I start dismantling cthe whole thing

 

Well very easily actually. Install the boost leak tester on the throttle body/ intake manifold. Apply shop air and if there is a blown head gasket (providing it is leaking externally) you will hear/ feel the air escaping as you rotate the motor by hand. If the leak is internal than check for positive pressure in the coolant system (while cold). I've done this a few times with Diesel engines and been able to locate exact failure location. Obviously air will bypass the piston rings but not before escaping the weakest point. Bent valves can be heard quite easily especially if you rotate by hand nice and slow. Monitor the valves visually with the rocker covers off. For example, with air on intake, if you have a ton of air escaping to the exhaust ports than you know either the valve is bent which would sound like crap regardless while running or the valve is not seating/ sealing. This can be the trickiest part to diagnose due to valve over-lap. Does this click for ya?

 

yep makes since to me was gonna go do the compression test anyways but was freezing so decided to wait for a warmer day.

 

Did the compression test and 4 of the 6 was over 100 was cranking somewhat slow though. Anyway the 2 that were 0 was the last cylinder on the drivers side and the front on the passenger side so started tearing down the engine to pull anyways.

 

0 PSI in two of them and 100 PSI on the others, is that correct?

Must be mad looking engine inside

To the upside... whats the plan?! Replace engine with some none VQ or full forged?

 

Yep that's correct I even checked them multiple times to make sure. bottom end is forged already got the receipt and build specs from cosworth so more hoping that the stock springs collapsed or somehow bent a valve in the process of getting the engine pulled now. But while it's out everything is getting Refreshed.

 

Didn't look too damaged just looking through the plug holes Although can't see much

 

take some pictures of your findings, would be interesting to see what is it.

Lucky that you are able to check it out yourself rather then handing it into a shop!

Did you speak to the seller yet?

 

Yea I had talked to seller right after it happened and he basically said whatever happened was my fault... He said he drove the car for several years and DDed it for one of those. However he did say he wasn't smart enough to do his own work And it was his first turbo vehicle. So oil seals I can see him damaging pretty easily by not letting it cool down for a few minutes but compression and stuff not sure. I prolly did that one playing around too hard and too long

 

So you took it for one boosted pull aside from the test drive?

I doubt it's your fault, unless he sold it to you "un-tuned"

He probably beat the crap out of that car then dumped it off to the first person who would pay for it. This happens all the time with modified cars.

If you bent a valve, you're gonna have a damaged piston and more so...

 

Yea true but it's my problem now so I may as well have broke it lol. Good thing is however motor is out tomorrow provided I can stay awake and motivated. Got moved to third shift and still trying to adjust.