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Hi All,

New to SAU. Excuse my limited knowledge for future reference.

I recently purchased a N/A r33 S1.5 (s2 management) with intentions to go down the forced induction path.

I purchased a Rb25det s1 engine,loom and ecu. I installed the engine trouble free but had a few electrical bugs, using the s1 management I can not get injector or coil pulse. I've tried multiple CAS with no luck and have narrowed it down to no power to the Ecu.

I then tried using the N/A s2 ecu,loom and plenum with all n/a sensors.

(Of course changing coil packs,tps and afm)

The car started and idled fine but run like shit on boost.

I changed to a S2t ecu,fuel pump and adjustable FPR

The car run what I thought was perfect.

After a small drive I've found it runs VERY rich @ idle and VERY lean on boost >4000rpm roughly

It's like the Ecu is not recognising "boost"

So this is where I am at now:

S1.5 car

S2det Ecu (only 1 relay next to ecu)

S2 N/A loom

S2 N/A afm

S2 N/A plenum and sensors

Det injectiors

Adjustable FPR @ 30psi- I've noticed a lot of fluctuations in pressure- some days 10psi some days 35????

S2 coil packs

S2 Tps and TB

Walbro 225lph

Boost T @10psi

So to me I belive there are no ways the car can sense boost since I do not run a boost solenoid using n/a loom?

The car will get up and go ok but feels to have no torque. It's just all noise.

I come back off the track with a glowing turbo.

The car will idle insanely rich to the point where the plugs fowl after 2 mins of idle @800rpm

The car will run amazing and pull well sometimes but very moody on when.

Also wondering if it's my fuel pressure fluctuating?

Let me know any troubleshooting ideas anyway guys and girls!

Look forward to joining the SAU community.

Max.

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I came in here reading the word milkshake expecting you to have blown a headgasket or the oil cooler.

You are correct. There is no "boost sensor". The load sensor is the AFM. It helps to use the correct one for the ECU and engine type.

It sounds as lean as f**k too. That could be because you have the wrong AFM, or it could be because your fuel pump is not up to the task. You should not do this sort of crap without having some basic test gear hooked up. Fuel pressure gauge sounds like a good one.

  • Like 1

I meant milkshake as in a bunch of different parts in one car haha,

Ok so there is a difference between a DE and DET afm?

Yes it is lean above 4k, I have a narrowband as a rough reference, I know they are pretty basic but still gives an indication

Yes my fuel pressure gauge jumps over the shop a bit.

So are there any differences to engine operation between the N/A and DET loom?

Thanks for your reply mate :)

Okay you will need the Afm from the same car the ecu came from.

You also need to set base fuel pressure to 45 psi with the FPR unplugged from the vac/boost source

Ignore the narrowband gauge they're worse than useless

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