Exhaust system gaskets

Might have the head checked for warpage and cracks and change the head gasket. The exhaust manifold gasket has no coolant that comes into contact with it.

It leaks what... coolant or exhaust gas?
If it's exhaust gases it's more likely to be the exhaust manifold gasket at fault.

If it's coolant leaking out somewhere it could be a hose/radiator/coolant tank, though coolant can also leak from the head gasket area.

A classic sign of a leaking head gasket is a creamy white/grey sludge on your oil dipstick. This is caused by coolant finding its way via a blown head gasket into the oil system

A creamy sludge on the dipstick - caused by coolant finding its way into the oil system because of a leaking head gasket.

Other indications of a leaking head gasket/head is overheating and rough running.

You can also try removing the cap from the coolant bottle and letting the engine idle. If bubbles continually appear this may be due to the exhaust gases finding their way into the cooling system via a leaking head gasket.

In most cases replacing a head gasket requires the cylinder head to be skimmed as well. This is because the alloy of the head tends to warp slightly.

A workshop would be able to diagnose a faulty head gasket within minutes. Having a head gasket replaced and the head skimmed isn't a cheap job.

Nowadays there are 'guaranteed head repair' additives available. Just follow the instructions on the can if you decide to use one. I personally haven't used such an additive.

It is common to see white exhaust smoke when first starting a car, especially on cooler days. This is generally steam caused by condensation. As the engine warms up and the condensation dissipates the white exhaust smoke (steam) is no longer seen. If excessive white exhaust smoke is present well after the engine warms up, it is necessary to have the car inspected for possible internal coolant leaks. Indicators of an internal coolant leak include billowing white exhaust smoke accompanied by a sweet odor or a low coolant reservoir level. An internal coolant leak can also contaminate the engine oil giving it a frothy, milky appearance. Even small amounts of coolant entering the combustion chamber will produce white exhaust smoke. One of the main causes of white exhaust smoke and coolant loss is a cracked or warped cylinder head, a cracked engine block, or head gasket failure caused by overheating. A cracked head may allow coolant to leak into one or more cylinders or into the combustion chamber of the engine. Dirty coolant, a poorly maintained cooling system, a low coolant level, or a non-functioning cooling fan can cause engine overheating. In addition, engine wear can eventually cause the gaskets to lose their capacity to seal properly allowing internal coolant loss. Intake manifold gasket and head gasket failures are two of the most common sources of internal coolant loss caused by engine wear.
Never remove the radiator cap or coolant reservoir cap while the engine is hot or running as it can cause serious injury; always allow the car to cool down completely first. Checking for a low coolant level in the reservoir is the first step in determining if coolant loss is causing the white exhaust smoke. If the coolant reservoir is at the proper level but excessive white exhaust smoke is present, a cooling system pressure check is required to determine where, if any, coolant leaks are located. THESE LEAKS WILL CAUSE SEVERE ENGINE DAMAGE! Have the car inspected immediately.

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Internal coolant leaks can and will cause

bank one upstream oxygen sensor on exhaust manifold bank two oxygen sensor after catalytic converter.tell me what code you are getting.bank 1 sensor 1 fuel system is too rich fuel pressure too high fuel pressure regulator leaking or more than 1 fuel injector leaking. fuel contaminated.check spark plugs if black carbon color fuel system too rich. if you getting code bank 1 sensor 2 check for air leaks in the exhaust system, air leaks intake manifold.look for vacuum lines leaks,look for vacuum leaks pcv valve and hose and make egr valve not stuck open or gasket leak.

How about a crack in the cylinder head or a gasket leaking into either the inlet manifold and being sucked into the engine, or being blown into the exhaust system and being boiled away. Ask a radiator repair shop to carry out an O2 test on the coolant. They may detect presence of the gas in the water confirming a leak into the exhaust system.

There are several areas to check for possible exhaust leaks. i will list them below.

1. Exhaust manifold gaskets - This will be the most common area. There is a gasket that separates the block from the exhaust manifold. these gaskets can fail, thus, causing a exhaust leak at the manifold.

2. Lower manifold gasket(donut gasket) - This will be a possible leak spot as well. This small circular gasket is placed in between the upper exhaust pie and the lower side of the manifold. It basically separates the pipe from the exhaust manifold.

3. Exhaust pipe - The entire pipe can rust overtime, thus, creating small holes along the pipe structure. These holes will cause the exhaust to leak ,thus, filling the vehicle will moderate fumes and causing louder than normal engine sounds during revving.

4. Muffler - This component can also deteriorate to the point that it cannot filter out the noise. It will also cause leaks as well.

You will find the leak in one or all of the areas stated above in the list.

it means that if u have a catalytic converter then ur catalytic converter which reduce the emissions is not working in proper manner which it means that it is broken

sounds like you need to replace the exhaust gaskets if you replaced the exhaust or even took it off to check. these metal gaskets crush when installed.

Check carefully around the valve covers, this is the area that leaks most frequently occur, and being located next to the exhaust manifold can easily cause the burning smell. There is a very easy to replace gasket under the cover. Other possibilities, shop or you when changed or added oil spilled a bit and that has worked down to the exhaust manifold and is causing the burnt oil smell. Last possibility is that you do have a slow leak on the underside of the engine that is blowing back onto the exhaust system causing the smell.

Have you checked the flex pipe section under the engine, and the gasket between the manifold and cat/flex pipe section? Those are two places they usually start to leak from either a blown gasket, or the flex section rusts out under the protective covering.