I have an exhaust leak that I can't seem to find. Its audible when driving, and I can smell an exhaust smell under the hood when I open it up. What are the different ways to find them?

 

You could always buy a cheap automotive stethoscope and see if you can audibally pinpoint the leak that way. The higher tech way of doing it is to use an exhaust gas analyzer machine. You could always run a wrench over the header and collector bolts as well to see if that cures the problem before going any furter with it, if a leak were to be present anywhere, I would put my money on either of those two places.

 

Get some Seafoam engine cleaner, and dump it into a vaccum line like the instructions on the can say...you'll get plenty of smelly white smoke out anyplace the exhaust is leaking! I discovered this working on a thirdgen several years ago, and it sure beats the conventional methods! No guesswork.

 

Transition fluid in the vacuum line works 10000x better than seafoam

 

I think you mean transmission fluid. Ya, run this through your engine if you want your cats and O2 sensors to possibly fail.

 

stupid spell check, I doubt the transmission fluid is any worse on the o2 sensor and cats than seafoam is, and the transmission fluid takes less to take effect than the seafoam

 

There are only so many places our cars can have an exhaust leak. Its either at one of the flanges, or at the manifold. If its audible then you can look at the manifolds and most likely you can see with your eyes if the gaskets are leaking. It could be at the manifold/Ypipe flanges, or it could be coming from around the cat and intermediate pipe. If you can get the car on a lift and I dont know what type of exhaust you have, but get a friend or 2 to block the tailpipes so that no exhaust gets out and go under the car and spray potential leak areas with water. With the exhaust tips blocked the water will bubble if there are leaks. Dont hold the exhaust in for more then a few seconds at a time, but it is an effective way to see a leak. I would not be putting any fluids in the engine that dont need to be there. If that does not show you anything then the leak is most likely the manifold gasket or at the ypipe and manifold.

 

Except the trasnmission fluid isn't solvent based like Seafoam. Seafoam is actaully safe for cats and O2s because it doesn't coat or leave a film. Tramssion fluid is like burning oil and will leave residue. Ya it could burn off, but is it really worth the risk?

If the car didn't have cats or O2's I'd say use the transmission fluid.

 

seafoam is petrol based just like transmission fluid. transmission fluid is an excellent solvent, I use a mixture of diesel and transmission fluid in my parts cleaner, works better than simple green or purple power.

 

Id stick to the water on the pipes method. If its as loud as you say it is, it should not be that hard to pinpoint. I have one on my camaro at the manifold and I can clearly see where the leak is. The manifold gasket has moved off the block and is leaking, it happens over time. I aint worried about it since I got headers goin on soon.

 

Check to see if either of the rear bolts for the exhaust manifold are broken. It is very common for these to break off in the head. Then you can get aftermarket headers like me and that bolt is not used, so problem solved. I used a paper towel roll and found a leak in the air pipe on the top of the exhaust.

 

But Seafoam contains much lighter/readily combustible solvents when compared to transmission fluid. Would you put diesel in your engine? If you did your O2's and cats would fail also. Why? It'll leave residue that coats the O2 and stops the catalyst process. They make Deisel specific cats for a reason.

 

Why wouldn't you want to put jet fuel in your car?

 

Did I say in your engine? No I said in my parts cleaner, I don't run my parts cleaner fluid through my engine. My point was that transmission fluid is combustible solvents, it burns no problem. Do you know what they do with used transmission fluid? They burn it.

 

put the running car up on a lift, get a buddy w/ a fistfull of rags, have him put his ragged hands over the exh tips. Then take a listen under every section of the exh. You'll find it.