What is the cylinder compression psi fpr the 2.0 liter engine

Radiator coolant in the engine oil is normally an indication of a failed cylinder head gasket or a crack in the cylinder head or both.

Running the engine in an overheated condition will cause head gasket failure and often a crack in the cylinder head.

The problem you have is coolant is escaping into the engine's lubrication passages via the failed head gasket or head crack and contaminating the engine oil. If not fixed you will cause further damage to the engine as oil contaminated with radiator coolant cannot adequately lubricate the engine.

Running a leak down test on each cylinder will confirm the leak. In this case you are going to need to have the cylinder head removed and thoroughly checked for cracks and any warpage as well as a new cylinder head gasket fitted. The condition the engine block surface will also need to be checked.

It can vary between make and model of car. However, a general rule of thumb is that 135+ average is okay. Less than 85psi is pointing at something seriously amiss in the engine.

It can vary - some cars may have 125psi as 'average' compression.

Don't expect each cylinder to give the same compression reading as there will be a fluctuation. Another general rule of thumb is that there shouldn't be more than 10% variation between the readings. That is, if cylinder No1 is 135 psi, cylinder No2 shouldn't be less than '125 ish'.

If you suspect you may have compression issues, it's quite easy to do a bit of fault finding. Warm the engine first so that the pistons are expanded in the cylinders. Then do a dry compression (normal) test.

Here's some examples of compression tests on a 4 cylinder engine:
130 127 129 127

All compression readings are within 10% of each other. Fine.

Example 2:
95 95 129 127
Here, a low compression reading on cylinder 1 and 2 suggests a problem. It may be due to a faulty head gasket/cylinder head allowing compressed gases to be transferred via the defective head gasket from one cylinder to another.

Example 3:
130 80 129 127
Cylinder No2 has a problem. It's compression is way down. The other three cylinders are fine. So .. what is the cause of the low compression on cylinder 2? It could be a broken ring/cracked piston or a burnt exhaust valve.

This is where you do a second compression test - called the 'wet' test.

Squirt some light engine oil into each cylinder. Aim for the cylinder walls so that the oil can find its way down the walls and around the piston rings. Place a rag over each spark plug hole and spin the engine to expel excess oil.

The oil that you have sprayed into each cylinder will form a 'seal' around the piston ring. Do another compression test and note down the readings. Here's example 3 again:
Example 3:
130 80 129 127
.. with the low compression on cylinder 2.

If after carrying out the 'wet' compression test you have a reading along the lines of
130 100 129 127
suggests that the bore/piston rings in cylinder 2 are at fault. The compression has increased on No2 cylinder because of the oil forming a seal around the rings.

If there is no increase in psi on the wet test i.e
130 80 129 127
This suggests a burnt exhaust valve.

How hot did the car get before you had to change the head gasket? If the car had extreme heat then it could have damaged the rings. The rings will collapse and allow oil to squeeze past and burn out of the exhaust causing the smoke. Also since the rings are collapsed the vehicle will have no compression hence the no start. First thing is do a compression check.

Are you sure it's actually a plug?
Are you getting oil on the plug?
The plug may be firing but you may be losing compression which gives the symptoms of a misfire. As you've changed the plug, lead and coil this points to to a problem elsewhere.

Your first course of action should be to get a mobile mechanic carry out a diagnostic check for you.

To put your mind at rest, do a 2nd compression test using a light oil squirted into the bores:

Doing a Compression Test
Warm the engine. Remove all the spark plugs.
Get a pencil and piece of paper to note down the readings.
Put the compression tester into the No1 cylinder and crank the engine for 10 seconds.
Note down the compression reading.
Repeat process for all cylinders.

Here's an illustration of what you may expect on a 4 cylinder engine:
Cylinder 1 2 3 4
psi 125 122 120 124

125 is the uppermost figure for that engine. Here, this engine is fine. There's a slight variation in psi figures, but that's perfectly normal.

Here's the same engine:
Cylinder 1 2 3 4
psi 110 112 114 112

The psi reading is down. However, as all the figures are pretty much equal it doesn't indicate head /gasket problems. It may point towards worn pistons or burnt valves.

Now consider these psi readings:
Cylinder 1 2 3 4
psi 125 84 86 124

There's more than a 10% drop - a difference - between cylinder 1 and 2, and cylinders 3 and 4.
The compression readings for cylinders 2 and 3 is down; low. There's something clearly wrong.

It suggests that there is a defective head gasket between cylinders 2 and 3 or a crack in the cylinder head. The rising piston compresses the gases which escape into the adjoining cylinder via the defective gasket or cracked head.

However, it could also mean that there is a problem with the valves (burnt/not seating properly) or perhaps piston / ring problems.

A burnt valve - it's usually the exhaust valve as they bear the brunt of the combustion - can cause a reduction in engine power simply because the combustion process isn't occurring properly. Compressed air/fuel gets squeezed out of that cylinder because of the damaged valve . There even may be a misfire - a surge as the car runs.

Worn or broken piston rings allow compressed gases to leak past into the crankcase. A compressed crankcase can force oil out of the dipstick tube. The pressure in the crankcase will leak to atmosphere anywhere it can find an outlet.

The 2nd Compression Test
The second compression test is known as a 'wet test'. The first compression test was the dry test because no oil was added to the bores. The second 'wet' test can give an indication of whether it is the rings or valves at fault (though bear in mind rings and valves do not cause overheating or water in the coolant symptoms).

Spray a liberal amount of light penetrating oil into each cylinder - aim for the cylinder walls, not the centre of the piston. You want the oil to run down the cylinder wall and around the piston to form a seal.

Place a rag over each spark plug hole and spin the engine to eject the surplus oil.

Then carry out a full compression test noting down the results.

Here's the previous results with the 2nd compression readings added:
Cylinder 1 2 3 4
psi 125 84 86 124
Wet 128 112 110 126

The readings have increased. This because the oil sprayed into the bores has formed a temporary seal around the piston, thereby enabling the compression to be raised. It also indicates that the bores/rings are worn on cylinder 2 and 3 - the 'oil seal' has increased the readings but is still low in comparison with cylinders 1 and 2.

This could also indicate that in addition to worn rings there is also burnt valves. Oil cannot form a seal around a valve. A worn or split valve will cause a low compression reading and misfiring symptoms.
Compressions readings should be taken in conjunction with other symptoms. It will help you identify the problem:

Low compression readings between two adjoining cylinders point towards a head gasket/head fault if your vehicle has shown signs of coolant loss, coolant in the oil system - mayonnaise, overheating, rough running and lack of power.

If those symptoms are not present it points towards burnt valves/piston rings. A worn engine may be difficult to start and pressurise the crankcase, but it doesn't cause overheating problems.

Pretty much same answer as I gave for 87 Reliant see below. Shops have equipment to do cylinder leakage test. Do basic stuff below before doing last test ...cylinder leakage...which costs $$$.

Main point you are losing antifreeze/water. Check to see if you have water on the dipstick mixed in with oil. If so...probably a head gasket. If oil looks normal..... Before you do any test, tighten every hose connection. Check for loose connection into antifreeze reservoir. Sometimes there are small cracks on top which lets out pressure from cooling system. Look for leaks on water pump and radiator. Look at spot where you park the car...any liquid on floor? Not sure?..Put piece of cardboard under car to see if liquid is dripping from car. No leaks?...Start with a pressure test of the system. The pressure test is simply equipment that replace the radiator cap, a hand pump connected to it then air is pumped into cooling system. You watch the gauge to see if pressure is dropping. If pressure does not drop ..problem is most like a worn radiator pressure cap or stuck thermostat.. Do not buy the kind with button on cap to push down and release pressure. get original type and correct pressure. If overheating still, thermostat could be stuck, replace. Overheating of engine causes vapor lock, bubbles in fuel, which causes car to stall and kill. When cools off, fuel cools down and fuel will flow through fuel system again. Large amount of oil disappearing with overheating also sounds like head gasket or cracked head....Tighten up all bolts to gaskets, look for oil leaks on garage floor or driveway. If engine has developed a miss when running, pull plugs out and look for wet fouled plug. If antifreeze leaking into cylinder...plug tip will be whitish, if oil leaking into cylinder, grimey oil fouled. Do compression test on cylinder that is fouled and that will pinpoint if bad head gasket or cracked head. When doing compression test, radiator cap is removed and you listen to hear bubbles in radiator from the cylinder leaking into cooling system. 87 Reliant not worth pulling engine apart if head gasket or cracked head. Best oil treatment to reduce oil consumption is "Engine Restore" Used on my 58 Impala 348 tri power for 28 years. If I did not add it after oil changes it used oil and smoked....I swear by it for ANY engine after 100,000 miles.

about 120 so this engine is well past its best or the head gasket has failed between the compression rings on the gasket

contact the parts store for specs they should have it on the computer system under overhaul specs..ask for a printout of rebuild proceedures..

see this causes and remedies, you can have overheating by internal leak or external leak:
1) transmission oil cooler is leaking , 2) loose cylinder head gasket 3) engine block cracke 4) cracked cylinder head or engine block bore 50 oirl cooler is (inside radiator) is cracker.

2) external: a) leak at the hose connection b) water pump c) core plugsd) thermostat housing e) cilynder head.f) gasket cylinder head.

God bless you

White oil means water or coolant is leaking in via Head Gasket Failure or a crack in the head. Along with repair - be sure to have each cylinder compression tested to see if there is a crack that has developed. Thanks for using FixYa - a FixYa rating is appreciated for answering your FREE question.

The ONLY way coolant can get into the crankcase is through a crack in the cylinder head, block, or head gasket. THE ONLY WAY!.

Checking compression was a good idea, and you've confirmed that is not where the leak is. It could be somewhere else within a head, the block, or head gasket.

Any gasoline engine will blow steam from the exhaust pipe on start-up and a few minutes running. May even stink, depending on how sensitive your nose is to smell.

I think your going to have to dig deeper into this, if you truly had coolant in the oil. But to tell you exactly where to look is not going to be easy.