Here is the problem, yesterday is my 2nd time replacing my coil plugs for my gd1. 1st time replace done in early 2012. my car just suddenly jerking at the 2 rpm during 60kmh. How do I know the faulty one among the 8 coil plugs?

 

I just changed mine at 227 for the first time.

Are you getting a check engine light? Get the code checked.

How many miles between coils?

Were the replacements of original equipment quality or greater? I've read about people having quality issues with cheaper options.

 

I didn't know that our car has 8 ignition coils xD

But back to the topic, start up the car first and then unplug one by one each ignition coil and if you notice a loss in power then that ignition coil is the one at fault.

 

Update:

Jerking happened again just now even after replaced with used set of coil plugs. Or, does the spark plug created the problem because it has been used about 80,000km. i am using NGK Iridium IK6 and IK7.

Skeletorspimpcane: I replaced with the used set. No check engine light on meter.

derykisonder: start with the front then rear ones?

 

Doesn't matter actually, just see which one will cause the result that you would want to have to diagnose it. I did this and found out my 3rd cylinder ignition coil was dead. Also if you haven't done it yet, maybe you want to do a valve adjustment as well.

 

Will try it tomorrow. Just borrowed 8 spark plugs from my friend for testing. Will it cause anything if i unplug the coil while the engine is running?