Loosing compression on #3 cylinder what do I do to repair?

Determine what cylinder is misfiring and do a compression test on that cylinder. Compare it with a cylinder that is not misfiring. You should have no more than 20% difference between the good cylinder and the bad cylinder. If it is low on compression, suspect a burn valve or bad valve seat... and it will require cylinder head repair. If it is good on compression, then look for a faulty injector or some other reason for the misfire on the dead cylinder.

Hi the very first thing which comes to my mind is why are the adjacent cylinders loosing compression, could it be a bad head gasket? let me know how you make out?

What probably happened is that the timing chain jumped time (common problem) and bent a valve in the #3 cylinder. This will cause the no-start, no-compression issue you state. You will need to repair the timing chain/gears/tensioner and have the head removed and repaired in order to get the car back to operating order.

a cylinder compression check is needed. You can do it yourself with the proper compression gauge available at auto parts stores. This check will tell you if the cylinder head gasket is leaking. Another good test is the Lisle 75500 combustion gas leak tester. This is less expensive but will show if combustion gases are leaking into the engine coolant--a sign of head gasket failure or a cracked cylinder head.

what plug look like on this cylinder ? do a compression check on all cylinders ? plug wire on this cylinder? cap & rotor look like ? is it smoking white ? loosing coolant? maybe head gasket? just have to start w/ plug & go thru these diagnoses to find the problem,,,,

The signs for a blown head gasket are:
1 - The car oveheats above 195F.
2 - The cooling system is loosing coolant, low coolant level.
3 - The coolant start boiling and owerfloing from the coolant bootle.
4 - Mixture of coolant in oil, or oil in coolant.
5 - White smoke from the tail pipe.
The diagnoses to reveal a blown gasket are.
1 - Radiator compression test. Can be done at any car reapair shop for $30.
2 - Static cylinder compression test. Can reveal at which cylinder is the blown gasket (pression low, or zero). This is very important at V6 or V8 engines.

Bad valve's will not burn oil, bad valve will cause a cylinder miss fire, due to you will loose cylinder compression, I would replace the valve seal's, Also do a wet and dry compression test, do a dry test, and write down reading's, then add oil in cylinder, and do another compression test, if in any cylinder's compression jumps higher then dry test, that's where your loosing oil, weak piston ring's.

First thing you need to do is determine why the compression in that cylinder is low. Four possible causes are 1. blown head gasket 2.bad valve(s) in the head 3. broken compression ring, piston ring land or burned piston. 4. rounded camshaft lobes
One other possibility is a fuel washed cylinder (from leaking injector)
You are going to have to remove that cylinder head and do a thorough internal inspection, possibly involving oil pan and piston removal.
Once the cause has been found you can proceed to make an appropriate repair. Or if the damage is beyond your ability, replace the engine with a used or new one.
There is no quick easy fix to restore compression.

If you can't locate the leak places, almost surely the engine is internally mixing water and oil, or even coolant is filling some cylinder. This should be clear by the oil and coolant condition, also by the smoke from the exhaust, if the case is severe. There are some additives for for the coolant, fixing small holes w/o opening the engine, but:
1. imo these additives are not very reliable.
2. The engine is probably already damaged and will need less or more repair.
3. Running with this oil-coolant mixture will block the engine for a very short time.
If you like your car and can afford it, think about a repair, for which plenty of stuff should be done and checked, just for example - all the bearings, compression rings on the pistons, cylinders and piston's geometry for ovals, the cylinder head for twisting or leaks, valves, etc. Best is to have the head with a special device like roentgen, in one word, to do all this alone you will need skills and knowledge beyond the even advanced driver has. If you absolutely want to do it by yourself tho, ask again and we will help.  

Hi tsmediaconce:

The water can only go one of 2 places, the crankcase or the exhaust. A blown head gasket could definitely be the problem. If oyu can get hold of a compression gauge you need to check the compression on each cylinder. If the head gasket is blown around the area of a cylinder you will see a low reading on that cylinder when you check compression.. Also chek the radiator for the presence of air bubbles. this indicates the head gasket is blown next to a water port.

The main thing to look for on the compression test is one cylinder that is markedly lower than the rest.

Hope this helps Good Luck Loringh Ps Please leave a rating if appropriate Thanks