Help- Stagea Missfire

[Nick666646]

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

[KiwiRS4T]

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

[Nick666646]

I'm not sure what sparkplugs are in the car. Or coilpacks. Bought the car with them in. Also I would turn up boost but it has stock bottom end? Wouldn't it blow 

[GTSBoy]

Should take >20 psi without damaging anything.  Just needs to not have whatever problem is causing the misfire and a check of the tune to make sure it was actually tuned to take the boost.

[Ris4rocket]

there're too many reasons. starting from bad fuel to fuel pump, injectors, coil packs, sparks.
I think you should better visit your mechanic

[Nick666646]

Fuel is 98, fuel pump is new and so are coils so I'm guessing sparkplugs

[Ben C34]

On 4/3/2019 at 6:51 AM, KiwiRS4T said:

What sort of coils are they? Many dodgy ones out there. 

 

[Nick666646]

Idk the brand but this is them

[niZmO_Man]

Yellowjacket? It should be okay, but lots of people had problems with them on non-standard engines. Gap the spark plugs to 0.8mm and see if that makes a difference.

[Nick666646]

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 

[Ben C34]

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. 

[GTSBoy]

Need more volts to bridge a bigger gap.  Only so many volts available.  Yellowjacket volts are also a mixture of randomly selected small and medium sized volts instead of a consistent selection of standard metric volts.

[Dose Pipe Sutututu]

3 hours ago, Nick666646 said:

Idk the brand but this is them

There's your problem.

[Nick666646]

3 hours ago, Dose Pipe Sutututu said:

There's your problem.

??

[Ben C34]

8 minutes ago, Nick666646 said:

??

 

8 minutes ago, Nick666646 said:

??

Yellow jacket coils are not good and are likely your problem

[Nick666646]

47 minutes ago, Ben C34 said:

 

Yellow jacket coils are not good and are likely your problem

Which do you recommend for my setup?

[KiwiRS4T]

OEM or Splitfire. There are other acceptable options but they require a little more work. Try gapping your plugs (if they look new - otherwise replace them as per above) to 0.8mm first.

[Nick666646]

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

[Ben C34]

Do more rev limiter to show it who is boss. And hope for some magical improvement.

Or get proper coil packs and fix likely cause of issue.

[Nick666646]

Gonna try some splitfires to see if that fixes. Do the rb25det and rb25det neos coilpacks work with eachother or do I need to get the neo ones coz my engine is neo (which I was told)