Would like to have your help cause i would like to make compression test. Do i need something like piece of hardware ? my car is a base model Neon 96 manual trans. with a 2.0L SOHC engine.

 

go to any auto store and buy a compression tester they run about $25. then pull one spark plug out and screw the tester in the spark plug hole and crank the engine 3 times. do that with every cylinder.

 

Thats all you gotta do. Its easy. You might want to get a book on the car while you are there, it will give you the specs for compression.

 

What should be the compression for a new car ? what is a good compression ? considering engine parts in my car are good.

 

u should be around 175 or higher

 

Thats right

 

Cheap gages can be inacurrate at time so instead of actual numbers as a hard rule some things to take into consideration. Is the engine cold or warm. If cold you may see stuff more in the neiborhood of 130ish. Also make sure you take all the plugs out then check. You what the engine to turn freely so you can check that cylinder. Also the thing you want to worry about more is that the cylinders are actually close to each other about 75%. I would worry less about a cold engine that just spun 105 on all 4 cylinders than one that spun 150 on three and 112 on the last. After testing, test again with 1 teaspoon of oil in each hole to see if the rings are leaking if one or more goes up considerably then you probably have worn rings.

Now if you test warm then you should see the higher readins such as 170 etc. however not a real good practice to pull spark plugs out of a warm soft waluminum head. To many times you can pull threads. So Cold is fine just expect slightly lower readngs.

 

When i did mine i did it with the engine warm so i got higher numbers. also i only took one spark plug out at a time when i did it. i didn't take all 4 out. but you do have to take all the wires off. i also noticed that then end cylinders (1-4) come out with weaker compression then the middle cylinders (2-3). i was told that was normal so i didn't worry about it.

if you don't want to buy a set of guages you can rent a pair from autozone just make sure you get a good brand name (snap-on, mac tools) and a pair that they tested to make sure it works properly.

 

i get 60-70 so what does that tell me? i have a 2005 dodge neon 2.0 i pulled all the plugs out and done the test. am i not suppose to pull them all out then do the test or is it just one at a time? thanks

 

ok i got 88-92 on a cold compression test. is that normal?