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1999 Nissan Stagea

(rb25det non neo)

is an RS so is factory RWD. has been manual swapped using an R34 GTT box

Need help before I take to mechanic as could be a simple fix. When driving normally there isn't a noticeable misfire. But when on boost, especially as soon as boost starts to just past half max psi the car stutters coz the misfire but continues up the rev range. Usually it's once or twice when I floor it but sometimes it will misfire alot when on boost. Cold or warm it happens with both. The more I drive it the worse it's getting and have no clue what it may be apart from maybe sparkplugs but it's fine til it hits boost. Also on idle it runs a little rough. Anyone know any possible solutions or possibly what may cause this and what to check. Cheers 

-Any help is appreciated 

mods include:

gt2860rs turbo

Bosch 750cc injectors

Z32 afm

Sard Fuel Pressure regulator

3 port boost solenoid

HKS Bov

Walbro 255 fuel pump

Front mount intercooler

ali rad

pod filter

nistune ecu. 

Recently had new intercooler piping, new coil packs, new fuel pump and new turbo core

Tuned at hyperdrive making 277rwhp at 14psi

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Turn up the boost!

Would have thought you replaced the plugs when you did the coils. What sort of coils are they? Many dodgy ones out there.

Plugs NGK BCPR7ES (copper) or better PFR7G-11S

Try a smaller gap 0.8mm

19 minutes ago, Nick666646 said:

I'll do that tonight and I'll let you know the results. But may I ask what does the gap difference do to help? I'm far from being a mechanic aha 

Much like it is easier to throw a ball across a smaller lake, it is easier for spark to jump a smaller gap.  

Or it’s easier to shoot a ball of lightning from your finger  a smaller distance than a larger distance. 

  • 1 month later...

Sorry guys had a lot of work and never got around to doing so. Took out and clean sparkplugs. Gapped to 0.6 but problem still consists. (Car idles a bit better but still original problem is there) But found something weird. When driving if I give it hurts and bang off limiter a little bit the misfire seems to go away for 5-10 mins and then it's back? Really confused

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