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Misfire on boost under load


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Misfire on boost under load

Hi

Just fired up my car after 2 years (new fluids and battery and starts and idles fine). After warming it up reved it a bit in neutral and its all sweet.

Now took it for a spin up the road and whenever im about to hit boost the car misfires (well maybe not misfire but splutters)

Car has spitfire coil packs and from what i believe its not ignition related (boost would still kick in and it would misfire in neutral but i could be wrong with the skyline)

Also fuel filter and fuel pump was replaced around 2 months prior to garaging the car. Feels smooth when revved in neutral.

 

Any ideas what it could be and also what i should check

 

thanks

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My car did something very similar to this. It turned out to be the igniter. If it gets worse and worse as it gets hotter keep the igniter in mind. Good luck!

 

Edit; I'd probably leave this to last to check. Start with plugs, then the usual suspects, then maybe igniter.

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It's all the possible things.

Could definitely be coils.  Splitfires aren't magical - they age like anything else.  Coils will usually run the engine fine and misfire on boost.

Could be a dirty or otherwise wrong injector.  Lean misfire when the fuel rates rise.

Could be the igniter if you have one.

Could be the fuel pump is soft.  Or the FPR might be stuck open and it's going lean from that.

Etc.

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Why would you hesitate to get Splitfires?  That's nonsense talk.  They are the best option other than OEM, likely to be 99% as good.  Even OEM from Nissan is not as good as the original coils that were put in back in the 90s.

All I was saying when I said " Splitfires aren't magical - they age like anything else" is exactly what I wrote.  They aren't immune from the same issues as any other coil, meaning they can have the odd faulty one from new, and they WILL age.  I have a high load miss in my car right now - have to try to diagnose it soon.  It could be my Splitfires.....they've been in the engine for years, one or more of them might be going off.  Doesn't mean that they are not a good coil.

And, for those willing to do a little more work, there are plenty of other coils you could put in your car.  LS2 coils, Yaris coils, and dozens of others.

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Why would you hesitate to get Splitfires?  That's nonsense talk.  They are the best option other than OEM, likely to be 99% as good.  Even OEM from Nissan is not as good as the original coils that were put in back in the 90s.
All I was saying when I said " Splitfires aren't magical - they age like anything else" is exactly what I wrote.  They aren't immune from the same issues as any other coil, meaning they can have the odd faulty one from new, and they WILL age.  I have a high load miss in my car right now - have to try to diagnose it soon.  It could be my Splitfires.....they've been in the engine for years, one or more of them might be going off.  Doesn't mean that they are not a good coil.
And, for those willing to do a little more work, there are plenty of other coils you could put in your car.  LS2 coils, Yaris coils, and dozens of others.


Well yes you're right. There are arguably one of the best to restore power/issues based on price & quality compared to oem ones. The oem ones lasted about a decade or more. .. just wished the splitfires were built to last longer than oem that's all lol ;) but then again it's already priced cheaper than oem ... meh. ..

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Noob question but would all these things mentioned go wrong while the car is garage? Car was not even turned over 12 months prior to this issue.

Was thinking of draining the fuel and maybe replace the filter first then maybe fpr and then move onto plugs - coils - ignitor

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