Sxnjeet

I know this is a super old topic, but what ended up being the problem?

Okay so, please read this. car started and ran fine. got my tuned ecu by RSenthalpy, did a bunch of pulls to test it out and finally drive the car after half a year of it just sitting and idling at most. Everything was good, thing ran flawlessly and had so much power, didn't feel slower than a Prius anymore. Parked it back and turned it off. Next day, I install an AFR and start the car. Didn't wire anything to the ecu. Just gauge. Car started, but died out in about a minute. I figured it was cause my car was on a lift and the fuel was really low and old. I add 5 gallons of fuel, still cranks but no start. I remove all AFR wiring (tapped into double din acc and power wires but there was a nest of wiring there so I was worried I messed something up. tried to put it back to how it was prior to afr install.) Still cranks no start. Changed spark plugs with brand new ones Changed fuel pump with a new one (verified working) Did compression test , compression came back all at 150ish. All fuses are good, Relay seemed good but ill double check by switching similar relays around. Verified MAF is working - Ended up getting curious as to why fuel pump is not priming when ignition is on, so I cut the fuel pump ground and power and connected them directly to a portable jumper. I also disconnected fuel line to fuel rail to verify fuel is being sent. So with direct jumper power, the fuel pump turns on and shot gas everywhere through the fuel pipe that I had disconnected, so ny doing that, I verified no clogs in fuel lines or filter. - Tried starting the car with that jumper directly wired to power and ground, but car still did not start. I'm guessing its a CAS issue but im a little scared to check it without messing up timing or anything else since I actually dont understand how to check CAS lol. If anyone has any other suggestions or recommendations , please let me know.

Oh damn, I have not switched around any wiring on the harness at all yet. I had my ecu sent off to a tuner to tune for my setup and disable the turbo pressure sensor so there's no more fuel cut. Should I switch the pin around for the ring gear crankshaft position sensor? What types of symptoms would show if something is about to go wrong related to that? thank you

pretty much just finished my rb20neo + t and manual swap...let me tell you, it is a pain in the ass the first time. took me almost a year at this point trying to chase down minor issues. But, I think if I was to do it again, I could probably do it with almost 0 problems with how much troubleshooting experience ive gained lmao. So either +T and upgrade the transmission, or just LS swap it and throw in a CD09 lmao. there ya go

yeaaa that's why I haven't done any wiring to the stock ecu harness because I have the haltech, but then that leads me to the other question of "is the pnp harness really plug and play?" or would I have to still switch some pins/wires over because the pnp is for the rb25det neo harness, and not for the rb20de neo harness. was really hoping to find something to spoon feed me since so many people have done rb20neo + t conversions, but man this is rough.

so once I wire in a boost sensor, it'll stop the engine cut off? I found out which pin in the ecu/harness it is, I just have no idea how to actually connect it. if you have any advice on how to actually do that, please link me a video or something with pictures at least lol.

Hello, I'm trying to make this thread basically the thread with all the answers to common questions regarding specifically the RB20 DE NEO + T engine, that comes in the R34. Answers will and only should be provided by those who have done this conversion or actually have some relevant real life experience please. Please feel free to ask questions in the comments if you have any so other members can answer. I feel like this thread is really needed, especially with more Americans buying (unknowingly going to regret it too) rb20 neo r34s. My first question being - What do you guys use for tuning? I have purchased a haltech elite 2500 Plug and play kit for the rb25det NEO because the ecu plug is the same, but I am unsure if any of the pins would need to be repined to match. Second question that I see asked very often - After this conversion, did you install the boost solenoid/ actuator? I see many people doing a + T setup on their rb20 NEOs while running stock RB25DET NEO ECUs with no tune. I am wondering how they are going about doing that and consistently abusing the car because many of these people have had these untuned setups running for a very long time. That was my original plan, but my engine cuts out at 5 psi of boost using the stock ecu with no tune and no boost solenoid/actuator.

interesting. ive read and heard otherwise over the past year. ive been doing this +t conversion on a rb20 neo using all oem rb25det neo parts including the ECU, and im having engine cut out issues when I hit around 5 psi of boost. Everywhere/everyone ive asked has told me its because I never wired in a boost solenoid/actuator to the ecu, so the ecu isn't getting the right signal once it hits 5 psi of boost, causing the engine to get shut off.