About every 2k miles my check oil level light comes on. There are no visible leaks and my oil pan is dry to the touch on the outside. Does anyone know where my oil might be going? I had sombody tell me that it may begoing out my tail pipe.

 

You are experience a fairly common oil useage matter with the Northstar. Cadillac has a Service Bulletin for cleaning the piston rings and many members suggest a routine of WOT, wide open throttle runs to help cure this consumption. There are a few posts here on this. We will find them and point you to them.

 

From a previous post by Katzmans Caddy :

Low Oil, unfortunately oil usage in Northstars is common, but so common not to be a big concern. One of the best things about a Cadillac is it tells you about problems. Imagine driving around with low oil and not knowing it. Is it time for an oil change? Might be a good time to do a piston ring cleaning.

Here is what I know about this. You need to get the rings cleaned. This is a job for a mechanic and probably best left to the dealer. Cadillac says to use cleaner kit PN 12378545 and you need a Kent-Moore J-45076 induction/evacuation tool. Cleaner is added to the cylinders through the spark plug holes and allowed to soak for 2 hours. Next vac*** out the crude and excess cleaner then do an oil change. Also clean the throttle body and EGR valve at the same time.

After that make sure you check underhood every month or whatever interval you like but not more than one month, when you stop forgas fill up. This way you will be on top of all fluid levels that are critical for good performance.

 

I appreciate it man. About the EGR Valve. I did some research on what that part actually does and that explains alot to me.From myunderstanding... ifthat part needs cleaning it will make my car harder to start at times, sluggish at the start,and alsogiveknocking sounds while driving right? If that's the case then that opens up a bunch of problems I can fix.

Do you know of any websites I can order that cleaner and the induction/evactuation tool from? Sounds like I can do the job myself.

 

That cleaner is a GM part so you have to get it from the dealer. I am not sure they will sell it you because it is nasty stuff, chemicals you know. Ask them anyway. As far as the tool goes I'd just try the big auto supply chains. We have Princess Auto, Napa etc...try them. The EGR system is a bit trick but you can clean it too. The system on your 98 Deville has the valve which is on the drivers side of the engine on the intake. It has a series of pipes and passages that carry the exhaust gases from the exhaust manifold to the intake manifold and back into the combustion process. These pipes and passages can get clogged up with carbon and when the valve is carboned up and the passages are too your car will run like S**T. This sound crazy but to clean the pipes and pasages you need to make a tool to ream them out....a coat hanger would work on the pipes. The valve itself is probably easier to just change. For passages and the valve a Carb/Throttle body cleaner would work. Blocked EGR passages will also make the car run hot and could affect indivudal spark plugs by overheating them and lead to early failure or degrading. The Italian Tune Up helps clear carbon build up. Devilles get babied and the Northstar is a high performance engine, meant to be flogged. I just came home from a 500 km high speed highway run and I'm going to make a post about it.Oh ya!

 

Can't wait to hear the story, I'm sure you didn't baby her.

 

I'm pretty sure I can get the cleaner because my dad is a salesman at the local Chevy dealership in Pensacola. Thanks for the info man... I appreciate it.