Ok, so i recently bought a 2002 Z06 with an LG G5x3 cam, LG Longtubes, and B&B exhaust. The car had a slight smoking issue prior to buying it and I was told it was b/c of the tune it was running rich (the person I bought it from is my friend). So after I drove it for the first day it had said "Low oil level" so i filled it up and went on driving. Well it has come on a total of three times since I have bought the car. I took it to get tuned and was told the a/f was at 18:1... .....the tuner then adjusted the a/f to 13.8:1. Even after adjusting the was still smoke. The tuner thinks that there may be bad rings or bad valve guides. I called my buddy and he said he never had an oil issue and said that he was told it is a gas issue. The tuner then pulled the plugs and they were white showing that the car was running lean.

So my question is, what is the issue? Where is the oil going?

 

Step #1: is the smoke black or bluish?

 

Valve stem seals? Possibly they were incorrectly installed when they did the cam swap.

 

that is what we were trying to determine....we used paper at first in front of the exhaust and got no spatter on it so then we put some cloth infront of the exhaust and smelt that and it kinda smelt like oil more then fuel......

 

You can do a compression test to see if its the rings. You can just replace the valve guide seals (not very difficult at all) and you can look into the intake and see if the floor of the intake is flooded with excess oil, (which would indicate a PCV or crank case blow by issue.)

Burning excessive oil shoulld be also seen on the plugs as crusty brown deposits. How do they look??

BC

 

The plugs are white and the PCV is clean.

 

Our LSx motors are famous for blow by issues at high rpm....is the PCV venting to atmosphere, catch can, or to the intake? I highly doubt your PCV is clean if its properly routed. Unless you have a catch can, all LSx intakes will have oil in them due to crankcase pressures and windage issues. The pcv can also throw off your AFR, causing a "false rich" condition when it burns oil...which would cause a tuner to lean the car out....hence the 18:1 condition you found at WOT.

Fill the oil to an exact level and drive around for X amount of time without revving over 4000rpm and see how your oil consumption is. If you're still burning oil at less than 4000rpm, it sounds like valve guide seals or rings.

I know my car consumes some serious oil above 6000 rpm due to "ring flutter" but it won't use a drop if I only rev to 5000.

 

EXACTLY!

BC

 

Well the tuner i used also builds cars and he ran through everything he could think of....he pulled the PCV and used a q-tip in it and the q-tip was clean. There is no catch can and the smoking is primarly at idle. And if the rings were bad or the valve guides were bad wouldn't that show on the plugs?

 

Then it can't be hooked up right! There would have to be some oil vapor in there. I have a LS6 pcv conversion AND I run a catch can, AND 3 breathers on the valve covers, and I still get a little mist in the filter that is right before my PCV valve.

 

Im not trying to argue with anyone....I just thought that a guy that builds 9 sec cars and tunes for a living would have realized if something was connected wrong.


I also just put a call in to the guy who did the cam install, which is a friend too. He works at a performance shop as a head tech....i want to see what his take is on this. Im going to be very pissed if this car has bad rings considering I got rid of a newer car with a warranty and was promised that this is a fuel issue.

 

Even professionals make mistakes. We're not calling him an idiot, just saying what the problem seems to be. We're trying to help you.

No oil in your PCV not only says that something is wrong in the PCV, but also that you "probably" don't have a ring issue, since the crankcase pressure that would be developed with a clogged or malfunctioning PCV would manifest itself in huge leaks from all the seals, and/or oil consumption problems that would be seen on your plugs. Since plugs are white, it is very likely NOT a ring problem.

I'm voting on your valve covers/pcv being vented to atmosphere and thus you're dumping huge amounts of oil at high rpm rather than reclaiming it and controlling further consumption by keeping your crankcase negative (vacuum). Some members talk of catch cans filling up with several pints of oil at the race track until they put in a PCV restrictor orifice.

 

ok, so ill double check to make sure that everything is connected right.

 

So i just spoke to the tuner again and he said there was a very slight amount of oil in the pcv but nothing that would cause that problem. He said he thinks it is valve guides......

 

Ok, now im lost...the installer said he thinks it is rings.....im just going to have the car looked at....this is dumb

 

Does it still apply like with the "oldschool" cars; if you had bad valve steem seals there would be a puff of blue smoke coming out of the tail pipe on take off from say a stop light or after idling for a while?

My C5 never used oil until I went to a H/C change. I installed a catch can and the new truck type PCV. This has slowed down but not stopped my oil usage. My $.02

Sleeper

 

The 02 got the newer Napier ring design so I would be less suspicious of the rings unless the car has been abused. I would concentrate on the seals and guides and the PCV, with the PCV being the first thing to thoroughly go through. Can you follow the hose routing and post what you find just to ensure it is correctly installed? You would be surprised some of the ways they have been incorrectly re-installed after extensive work. Pull the intake coupler, take a flashlight and open the throttle body blade and look into the intake. I found a puddle in mine (from the PCV system). Mine is also an 02.

How many miles on the car since the cam installation? What valve springs are you running? The stock rockers have a very poor wipe pattern that is wide and on some cars off center (to the side of the stem). Installing more stout aftermarket valve springs will hasten valve guide wear.

What is the heat range on the plugs you are running? The white could be the result of too hot a plug as well as the mixture.

Aftermarket dual springs require installation of the older style umbrellas seals. Incorrect installation can result in them coming off of the valve guide and letting oil in.

 

does anyone know if thicker oil (or some other trick) will help the ring flutter problem on the earlier "Non-napier" rings? My cylinders on my 1997 are still perfect (the cross hatch was still there after 120,000 mi) but I have significant oil consumption at high rpm due to ring flutter.

I really don't want to yank the motor just to do rings....since I'll end up doing a forged stroker while I'm in there......

 

As SleeperC5 said about the valve stem seals, I had the same thing on mine. When I would take off from a light, got a puff of oil smoke from it. The cause was improperly installed valve stem seals as a leftover from my having replaced the lifters. While I had the top end off, I had the heads worked on at an engine shop where I provided new seals and springs. They messed up the seals by supposedly using the wrong tool to install them. Replaced them again, oil problem solved.