Hectic

iTrader: (20)

This is maybe the most frequently asked question in the 3rd gen section. A rough running engine in a 3rd gen is most often caused by a bad fuel injector. When your engine is running rough, you can have the problem diagnosed in a matter of a few minutes. Simply look at the source.

-Pop your hood and start the car

-Pull each spark plug wire or coil pack harness one at a time and note whether or not it has an impact on the idle. If the idle drops when you pull a plug wire or coil harness, the corresponding cylinder is firing, if it has no effect on the idle it means there is no detonation inside the cylinder. Do this with each of the six plug wires or coil pack harness', replacing the wire or harness when finished. You should now know which cylinders are firing and which are not.

-The next step is to check for a spark by using a spark plug tester or the old fashioned way which involves replacing the plug with a dummy plug, and touching the plug threads against a ground point with the plug or coil pack connected. You can easily get shocked by doing it this way and perhaps cause damage to your car's electrical system so a plug tester is reccomended.

-If the plugs are firing correctly you can just about rule out any component in the electronic ignition system unless your wire is shorting out somewhere or the coil pack is cracked. For wires, start the engine at night and look for sparks in the engine bay. For coil packs, just pull and inspect, the cracks will be obvious.

-If all above tests pass, then just for confirmation there isn't a more serious problem to be prepared for, you can run a compression test. It's unlikely the test will fail if your only problems are a rough running motor. But if you have a compression guage on hand, it can't hurt to test (unless you end up stripping your plug threads)

-If all above tests fail, it means the corresponding fuel injector for the misfiring cylinder is faulty and needs replaced.

MAXIMUS G EKSUS

Thanks dude, very informative !