Missfire Developing When Hot - Code 21 - Ignition Wiring

[Zz_32]

Hi,

I've been battling a problem for the last month with my r32,

I drive it for 20 mins or so and all of a sudden it sounds like it has dropped a cylinder.

I have been reading alot of similar problem stories online in hope of an answer as it seems to be a common problem.

However what is causing my problem does not. So i thought I would write up about it in case someone else

comes across the same problem and hopefully understand a bit more myself.

So far I have replaced the following:

Spark Plugs

Coil Packs

Fuel Filter

Fuel Pump

---

Took out ECU and ran a diagnostics test, Came up with Code 21 - Ignition Circuit Problem

Alright so wtf do I do now. Haha ended up checking earth points, nothing.

Played with the PTU (Power Transistor Unit) / Ignition Amplifier while the problem was occurring, pushing around the plug on the right side and

It acted up a bit more / would unsteady the idle briefly. HMM bingo

Or is it? I have a new Coil Pack harness on the way seeing as i might as well replace that too. But I'm unsure what to do about the PTU

I have no multimeter or the slightest clue how to test it, other then its f**ked get a new one. However I would like to know my options regarding it first and my ECU for that matter if anyone could shed light on the topic that would be exceptional. Cheeers

[DVS JEZ]

Best way to diagnose would be to borrow/try a known working ptu, coilpack harness and ecu, try 1 at a time to see which is the problem

[Zz_32]

Best way to diagnose would be to borrow/try a known working ptu, coilpack harness and ecu, try 1 at a time to see which is the problem

Yep well I put in a new harness today and reset the ecu and it still acts up so, I do know a mate with one so hopefully he lets me borrow his ptu, then I think i'll get it tuned. Thanks mate

[Moodles2]

Could try rapidly cooling the ignition amplifier with some ice cubes on top to test it, when they are worn out they tend to only do it when hot.

[SargeRX8]

Heat from the engine will heat up the electronics and when electronics heat up, they run inefficiently, especially if worn or failing. Try a new ignitor.