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Missfire Developing When Hot - Code 21 - Ignition Wiring


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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

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 :yucky:

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