My 2004 Z20NET GTS

[LastOne]

If I have interpreted this control function incorrect then so be it.

Eh? If you've misunderstood what you're talking about and therefore sent someone on the wrong path as to how they should maintain their engine "then so be it"?

[LastOne]

I thought the trionic version detects this via the ionisation rate from the from combustion detection module that is sseparate to the ECU. I note that the CDM has four inductive ignition coils, one for each cylinder, with a power stage and with this ionization current measurement I thought that this that performs the initial signal processing via in inbuilt algorithm of the ionization signal detecting to obtain knock detection. Although this ignition system receives four ignition trigger signals from the ECU but gives two combustion signals to the ignition system ie the wasted spark plus one knock signal to the ECU. I don't interpret this as igniting all........

Nick, you need to stop copying and pasting paragraphs wholesale from the internet (this time from pelicanparts.com) without understanding what the text says or verifying that it's actually accurate.

[NickT]

I still don't interpret that the system fires all of the spark plus at the same time.

Obviously I don't know the topic at all and you have shown better knowledge and understanding on all matters in their entirety. I clearly stand corrected and apologies to the Op.

[LastOne]

I still don't interpret that the system fires all of the spark plus at the same time.

Obviously I don't know the topic at all and you have shown better knowledge and understanding on all matters in their entirety. I clearly stand corrected and apologies to the Op.

Well then let me be frank then nick. Does it make a material difference how you interprete the firing system, given that you don't drive a Z20NET engined car, you're not likely to be buying spark plugs for one anytime soon, you've never changed the plugs on a 'NET (we know that because you were assuming it has a coil "pack"), you've never held a dirty plug from a 'NET in your hand and had reason to ponder why it's in that state so soon and you wouldn't know that the Z20NET must only be fitted with one particular model of NGK plug (PFR6T-10G) unless you read it on the specification sheet I wrote on this forum years ago. My point is that this is a hypothetical discussion to you, not a real one, yet you've chosen to try and influence it anyway, despite not taking the time to avail yourself of the necessary facts. In return for your sarcasm about me having better knowledge of everything in their entirety I will point out that your contribution to this discussion was to paste some unverified information you found via Google and preface each paragraph with "I believe..." expecting us to think you wrote that paragraph. You drive a 3.0 diesel I believe, and I'm sure you wouldn't think highly of me if I insisted that the SCV problem some of them suffer from can be sorted by cleaning the affected part with crunchy peanut butter...

[NickT]

Than you for your etiquette reply. Much appreciated. I think highly of people based on who they are.

[LastOne]

Than you for your etiquette reply. Much appreciated. I think highly of people based on who they are.

[Entharion]

I'm just going to ignore the part where the conversation went off the rails, but I'm glad to see it's resolved

Thanks for your explanation LastOne, I guess I'll have to change the plugs more often, the Colt plugs were €80 for a set so doing this in half the km's doesn't really make a difference in cost in the end.

Still lacking deeper understanding I did some looking around and found an article describing how the Trionic knock detection works, it's a short but informative read: https://www.eeuroparts.com/blog/5436...ation-sensing/
Our cars with the Z20NET should be a Trionic 8 right? I guess I should dig into it some more... If you have any good articles, forum pages or papers you feel I should read I'd love to get those.

About my remark on the oil, I've not done a single oil service on this car myself as I've only had it for 6000Km and the timing belt was done 5000Km ago by a shop. I guess I just prefer to do my oil changes a bit early for peace of mind.

[08estate]

I'm just going to ignore the part where the conversation went off the rails, but I'm glad to see it's resolved

Thanks for your explanation LastOne, I guess I'll have to change the plugs more often, the Colt plugs were €80 for a set so doing this in half the km's doesn't really make a difference in cost in the end.

Still lacking deeper understanding I did some looking around and found an article describing how the Trionic knock detection works, it's a short but informative read: https://www.eeuroparts.com/blog/5436...ation-sensing/
Our cars with the Z20NET should be a Trionic 8 right? I guess I should dig into it some more... If you have any good articles, forum pages or papers you feel I should read I'd love to get those.

About my remark on the oil, I've not done a single oil service on this car myself as I've only had it for 6000Km and the timing belt was done 5000Km ago by a shop. I guess I just prefer to do my oil changes a bit early for peace of mind.

Interesting link.

This extract suggests the 'wasted spark' situation where all 4 spark plugs are firing at the same time only happens for a short period on initial startup:

"The only time that this active timing doesn’t take place is when you just start the engine. Upon initial startup on a Trionic engine, all Saab engine parts, including the spark plugs are firing at the same time, using a much older process called “wasted spark“. That just means on cylinders that aren’t combusting (exhaust stroke), the spark is ‘wasted’. During this phase, Saab Trionic is getting its bearings."

It sounds like once this period is over that normal sequential ignition (one spark plug firing at a time) takes over.

[Dog_Book]

Whatever the reasons I would ignore most vx service intervals and follow old rules. For eg I think the cdti oil change was yearly or every 10k miles which is to high at that miles the oil is like sludge. Yeah if your doing a few thousand miles a year ok but not that. I forget what the interval is for the 2.8t plugs it might be something stupid like 4 years. I had it in my head to do them every 2 years and my last plugs failed about 18 months after being replaced and the previous owners garage had fitted all 6 and were genuine gm and the correct gap so there you go for mine if they haven’t died at 2 years they are ready to fail.

[Entharion]

It sounds like once this period is over that normal sequential ignition (one spark plug firing at a time) takes over.

It does appear that way, not sure if the Z20NET uses exactly the same system though.

Whatever the reasons I would ignore most vx service intervals and follow old rules. For eg I think the cdti oil change was yearly or every 10k miles which is to high at that miles the oil is like sludge. Yeah if your doing a few thousand miles a year ok but not that. I forget what the interval is for the 2.8t plugs it might be something stupid like 4 years. I had it in my head to do them every 2 years and my last plugs failed about 18 months after being replaced and the previous owners garage had fitted all 6 and were genuine gm and the correct gap so there you go for mine if they haven’t died at 2 years they are ready to fail.

I drive about 15K a year, every 10K I do the oil and I'm going to do the spark plugs at 20K, should work out just fine IMO.
The wear also depends on your driving style I guess, I rarely push it hard and the plugs were slightly fouled by rich mixture.