Not having fun with this rebuilt motor

[marni]

Hey fellas, hope you're all well

so here we go I need help

I rebuilt my R33 series 2 GTS-T from the ground up. 

The rebuilt motor is having trouble starting and idling. 

Rebuilt RB25DET series 2

Car kicks over then cuts out straight away, like its starved of fuel. Then when you try start it again it gets really compressiony doesn't want to start. Leave it for a min and it will, but with horrible misfire, eventually sorts itself out but not fully, hunts for a bit. Doesn't sound like it's running on 6 cylinders.

Head got rebuilt, had no issues with old one, piston rings were finished so I had to rebuild it

Compression ratings at 140 across all 6
Seems to be over-fueling but it's always run rich. 

I've checked the: 
 Coil pack loom, tested fine 
 Fuel pressure fine
 Oil pressures good
 Spark is fine 
 Timing is spot on 
 
 
New 
- Walbro fuel pump 
- Saads fuel reg
- Iridium spark plugs
- AFM
- K&N Oil Filter
- Gates timing belt 
- Nissan water pump
- Nissan thermostat

Old (off the motor before rebuild, but were working when dismantled)
- GCG high flowed turbo
- GCG FMIC
- Injectors and rail (standard series 2)
- ECU (standard series 2)
- Intake manifold (inc AAC)
- Exhaust manifold 
- Exhaust
- BOV
- Alloy Radiator
- Cam shafts
- After market boost controller 
- CAS
- Pod filter
- Splitfire coilpacks (haven't travelled more than 3000km)
   

Any suggestions for me to test?

I'm trying to organise a new CAS to test. 

We were test driving the car all week in our workshop carpark after we installed the new reg and it was running really well, but was doing this same thing over a week ago. Kinda reverted to doing the same thing again unfortunately. 

Id appreciate any help with it, it's so close but so far omg

Thanks for reading 

Marni

[AngryRB]

Id suggest testing for vacuum leaks and use a stock regulator.. 

[Birds]

Air and fuel, air and fuel

Check leaks as above

And possibly injectors not seated/connected properly or leaking/fked

AFM plug all good?

Stock ECU may not be happy with that regulator if it's upped the fuel pressure

[Birds]

Also not impossible to have a splitfire shit itself

You say it sounds like it's not running on all 6 - pull coilpacks and see if you can isolate which cylinder isn't happy, as that will narrow things down to a specific injector/coil/plug rather than overall engine air/fuel delivery issue

[KiwiRS4T]

Try the stock regulator. How much boost are you running? High flowed turbo with stock ecu does not sound like a good combination.

[marni]

It ran fine for like 9 years with that turbo and just an electronic boost controller 

haven't really had it on boost just yet cos it's not running right 

 

[marni]

When I had the stock reg on it test driving it was over fuelling and stalling as soon as you'd come of the throttle and the RPM would drop 

[marni]

3 hours ago, Birds said:

Also not impossible to have a splitfire shit itself

You say it sounds like it's not running on all 6 - pull coilpacks and see if you can isolate which cylinder isn't happy, as that will narrow things down to a specific injector/coil/plug rather than overall engine air/fuel delivery issue

They all seem to be working fine, it's like as soon as it cranks and starts, gets oil pressure then dies straight away, sounds promising for like 1 second and then cuts straight out

im wondering if it's a lazy lifter or something

although when i installed the last head and had a stuck lifter I had no comp in that cylinder whatsoever