What would cause a1984 nissan4x4 to loose compression in 3 cylinders

If you're still experiencing a cylinder 2 misfire in your 2013 Dodge Avenger 3.6L V6 after replacing the coils, spark plugs, and wires, there are a few potential causes to consider: 1. Fuel Injector Issue: A malfunctioning or clogged fuel injector can cause a misfire in a specific cylinder. Check the fuel injector for cylinder 2 and ensure it is functioning properly. It may require cleaning or replacement. 2. Compression Problem: Low compression in cylinder 2 can lead to a misfire. Perform a compression test to check the compression levels in all cylinders. If cylinder 2 shows significantly lower compression, it may indicate issues with the valves, piston rings, or cylinder head gasket. 3. Ignition Timing: Incorrect ignition timing can cause misfires. Ensure the ignition timing is set correctly according to the manufacturer's specifications. 4. Vacuum Leak: A vacuum leak near cylinder 2 can disrupt the air-fuel mixture and lead to a misfire. Inspect the vacuum lines and intake manifold for any leaks or loose connections. 5.Engine Control Module (ECM) Issue: A faulty ECM can incorrectly trigger a misfire code. Consider having the ECM scanned for any error codes or anomalies related to cylinder 2.

If your Mercedes C200 W202 is not firing on two cylinders, and you've already changed the coil packs, plugs, fuel pump, and filter, here are a few other things you can check:

1. Check the fuel injectors: It's possible that the fuel injectors on cylinders 2 and 3 are clogged or not functioning properly. You can check this by swapping the injectors with ones from another cylinder and seeing if the problem moves with the injectors.
2. Check the wiring harness: The wiring harness that connects the fuel injectors to the engine control unit (ECU) may be damaged or have a loose connection. Check the wiring harness for any signs of damage or corrosion, and ensure that all connections are tight.
3. Check the ECU: The engine control unit (ECU) may be malfunctioning and causing the issue. A diagnostic scan tool can be used to check for any error codes related to the ECU.
4. Check the compression: Low compression in cylinders 2 and 3 can cause issues with firing. A compression test can be performed to check the compression levels in all cylinders.

If you're still experiencing issues after checking these items, it's best to have a professional mechanic diagnose and fix the issue. They will have the knowledge and equipment necessary to properly diagnose and repair the problem.

Low compression on cylinder number 1 and cylinder number 2 on a 2000 Toyota Solara 2.2L engine could be caused by a few different issues. Here are a few possibilities:

1. Worn or damaged piston rings: The piston rings seal the combustion chamber and maintain compression. If the rings are worn or damaged, they may not be able to seal the combustion chamber properly, resulting in low compression.
2. Damaged or worn valves: The valves allow air and fuel to enter the combustion chamber, and allow exhaust gases to exit. If the valves are damaged or worn, they may not be able to seal the combustion chamber properly, resulting in low compression.
3. Damaged or worn cylinder walls: The cylinder walls are what the pistons move against. If the walls are damaged or worn, they may not be able to maintain proper compression.
4. Head gasket failure: The head gasket seals the combustion chamber and prevents compression from escaping. If the head gasket is damaged or blown, compression can escape, resulting in low compression.
5. Leak in the intake or exhaust system: a leak in the intake or exhaust system can cause low compression.

The dry compression test you did on cylinder 1 and 2, 80 PSI and 60 PSI respectively, are not within the normal range and indicate low compression. The wet compression test results are also not within the normal range, 95 PSI and 85

If the misfire is on one a particular cylinder or perhaps 2, these issues need to be addressed and checked...
1. Power to the spark plug.
2. Coils and spark plug condition.
3. Fuel supply to the cylinder
4. Air supply to the cylinder
5. Correct fuel/ air mixture to the cylinder
6. Cylinder compression. Low compression or a cylinder compression level below spec will result in a misfire. If the compression tester shows low compression in a cylinder the causes of the poor compression reading then need to be addressed.

The fault codes generated by the computer and read by an appropriate scanner will tell you which cylinder or cylinders are misfiring.

Compression is what happens when the piston comes up and compresses the fuel/air mixture. Then the spark plug ignites it and the explosion drives the piston down in turn, turning the Crankshaft in turn making the car go. A compression leak is when this compressed fuel/air mixture is escaping from the combustion chamber.. This can happen 3 ways. 1. Bad piston rings, 2. Blown head gasket or cracked head or block, (usually caused by overheating), Or the least costly.. loose spark plugs.

Broken or worn compression rings and faulty valves are normally the cause of low compression. I would suggest you take the vehicle to a larger reputable company for a second opinion to start with.

Carbon build up, burned valves and seats, piston ring wear, a general mechanic can tell you if the engine is having compression issues but you should have a cylinder leak test done to see where the problem is exactly.

You have a bad intake or exhaust valve

Major Repair

Check Lights are just an indication of a system
fault code set in vehicles computer

You use the codes to help diagnose the issues
if they are of any help

Codes & Sensors that produce check lights- just indicate
that something is not to programmed Emission Specs
& only component testing will find the problems

when you do your compression test squirt some oil in the cylinder through the spark plug hole first then check compression if you have compression then its rings. If still no compress you might have worn off cam lobes.

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.