Jump to content
SAU Community

Recommended Posts

When driving, my car will drop a cylinder making it sound like a wrx which I'm sure is to do with my YJ coils I bought a year ago (just changed spark plugs and it's still doing it). The problem is that it only happens randomly as it can happen within 5 minutes of driving or 30 minutes of driving which makes it inconvenient. Is there any way you can tell if the coilpack is faulty by just looking at them? Perhaps driving around at night with the coilpack cover off and seeing if it shows spark? Any ideas?

Edit: If I pull over when it drops and start the car back up, it will return to normal

Edited by Dani Boi

Visual inspection of the coilpack will show up and cracks or carbon tracking across the outside, but given that they're only a year old, they probably haven't suffered the sort of age related failures that you can see.

Best bet is probably just to find a set of known good other coils and either swap them all out and see if the problem goes away, or keep swapping them out one at a time until the problem goes away. Whichever way you go about that you will end up swapping one coil at a time if you're trying to find which one is at fault.

My old RB20 used to drop a cylinder every so often and restarting it did fix it most of the time. And it was caused by a faulty coilpack. Swapped them out with a known good set and it never happened again.

take the cover off coil loom, drive the car until it starts missing, then disconnect each cyl one by one.

one of them you will notice that the engine sound will not change, that is the cyl that you are having issues with. remove the coil pack at a later date and check the loom, also check the injector connector for that cyl too.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Latest Posts

    • Just an FYI.. I installed a ECU Masters det3 piggback. For the next few years car will remain N/A but it has inbuillt 4Bar map sensor , boost control etc if we wanted to use it for turbo conversion when the time comes. Though the plan is to do a manual conversion and go to a link ecu when that time comes.
    • Do a degree in mechanical engineering specializing in combustion systems and materials. Learn how to actually wrench on things that don't require 70k+ USD buy-in while you're at it. You also want to learn to weld and machine. If you still want to do this then you'll nominally have the knowledge to actually do what you're thinking of doing. Whether you still want to do any of that once you've actually gone through that process is anybody's guess. Personally I cannot imagine anything more frustrating than trying to package a supercharger under the hood of any of these cars when the turbos are already fighting for every last inch.
    • That's a function of the fuel pressure reg, not the pump. The pump can do more, needs to be able to do more. The reg keeps the pressure in the rail constant above whatever the manifold pressure is.
    • You need enough post count to have PMs enabled. It will come. They are not the same. The NA box is the skinny little box and the turbo box is the big heavy one, and the yokes are not interchangeable.
    • So, you're not talking about rebuilding the dampers, just putting new tops on them? You just need new tops and a spanner.
×
×
  • Create New...