Will faulty dsc light cut power to engine

If you have already checked the spark plugs, plug wires, fuel injectors, and distributor and are still experiencing a misfire in cylinder 1 and 2, here are a few more things you can check:

1. Compression: Check the compression in cylinder 1 and 2 using a compression tester. Low compression could cause a misfire in one or both cylinders.
2. Vacuum Leak: Check for a vacuum leak by inspecting all hoses and fittings for cracks, damage, or looseness. You can also use a smoke machine or propane torch to locate any leaks.
3. Ignition Coil: Check the ignition coil to ensure it is functioning properly. You can do this by swapping the coils from cylinder 1 and 2 with the coils from another cylinder and see if the misfire follows the swapped coil.
4. Fuel Pressure: Check the fuel pressure to ensure it is within the manufacturer's specifications. Low fuel pressure can cause misfires.
5. EGR Valve: Check the EGR valve to ensure it is functioning properly. A malfunctioning EGR valve can cause misfires.
6. PCM/ECU: If all other components have been checked and are functioning properly, it is possible that the PCM/ECU (Powertrain Control Module/Engine Control Unit) may be faulty and may need to be replaced.

It is recommended to perform these checks in a methodical manner to narrow down the cause of the misfire. If you are not comfortable performing these checks yourself, it is recommended that you seek the assistance of a professional technician.

I deleted the new boys answer. He is answering questions that don't make sense for points.

When the engine light comes on and is flashing, it is sensing something that may be an issue, when it is on solid, you do have an issue. Only a pro grade scan tool can read all codes including historical code entries. Of course when you disconnect the battery, you lose them all.

What I would suggest you do is move/swap the coils from Cylinder 1 and put it in Cylinder 2. Also check the wiring connectors on both 1 and 2 and give them a spray of electrical contact cleaner. Then run the car and see if the Misfire Code moves to Cylinder 1. If it does, then it is the coil that is faulty.

Also when you replaced the spark plugs, did you check the spark plug gap with feeler gauges, or were they pre-gapped plugs?

Check Engine Light/Misfire Due to Intake Valve Locks ...

repairpal.com > Problems > Jeep > Liberty

Jeep Liberty Check Engine Light/Misfire Due to Intake Valve Locks/Valves. ...Misfire cyc 4 and random cyc misfires, changed coil packs and plugs... sounds as if rod ... Light came on again (misfire on cylinder 4) - switched coil from 4 to 2. Light ...

Jeep Liberty Questions - Cylinder Misfire code - CarGurus

www.cargurus.com > Questions > Jeep > Liberty

CarGurusMay 27, 2009 - #4 misfire new plugs and coil pack on #4 light came back on after 300 miles if ... How come it stopped misfiring for 2-3 months, and now is back? ... I have a 2005 Jeep Liberty 6 cylinder, engine light came on scaned the codes ...

Liberty Cylinder Misfire / Computer issue? - JeepForum.com

P0304 is engine misfire #4 cylinder Several things can cause a misfire #1 electrical which you have covered #2 Mechanical Test engine compression is should be around 150 cranking and 120 running . internal valve train components can cause bad compression and the valves then self. #3 fuel injector can be the cause suggest swapping with a know good cylinder and see if misfire follows injector.

Not sure, but may be the timing is off. Autozone should be able to check it with a timing light. The timing setting determines the firing of the spark plugs. It it is off, it doesn't matter how new the spark plugs are.

cylinder 4 misfire ,now if this is a GM product then i think you may need a reconditioned ECU init as if this is the 4 cyl engine and its same as the opel astra and zafiro and the vectra then its a common fault with a 2000 to 2004/5 model the computer is bolted to the engine inlet manifold and very weak and susceptable

www.engine-light-help.com/generic-engine-check-light-codes.html

It sounds like a misfire. Check spark plugs 5 and 6. It could be bad fuel, bad plug wire, or weak coil. Check the fuel injectors as well. Other possible causes could be an egr valve stuck open, vacuum leaks, low fuel pressure.

I assume you know the problem is a misfire in #2 cylinder from checking the diagnostics code. Although these codes can be helpful in narrowing down a problem they lack specific details. In the case there are several possible items that could trigger the engine fault code P0302

These include:

• Faulty spark plug or wire
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector
• Burned exhaust valve
• Faulty catalytic converter(s)
• Running out of fuel
• Poor compression
• Defective computer

Before you spend any money to resolve this you need to narrow this list down even more. Start by pulling the plug. Do a image web search on "spark plug diagnosis". This will give you pictures of plugs with a variety of problems to compare with yours and give you an indication whether or not the plugs need replacing. Next if possible switch #2 plug wire with another. Make sure you switch both ends (coil end and spark plug end) of the spark plug wire.
These are the no or low cost options. Beyond these you will need to start replacing items like the Ignition Coil and O2 sensor.
If you are still having the problem after checking and/or replacing the items listed above, your next step is a compression test on #2 cylinder.
If you get to this point please repost here with the results with the wires and plugs and I will give you the steps to follow with compression testing.
Hope this helps.