RB25 No fuel after injector change

[the_dude]

Hello, I have an R32 Skyline GTST with an RB25DET. Yesterday I swapped out my stock injectors for new P2M 550cc injectors. I followed a tutorial online step by step, nothing went wrong. Went to start up the car and it cranks but won’t start. Popped off the fuel pressure line and no fuel seems to be going into the rail. I can hear the fuel pump kick on when I turn the key however. Any ideas? I’m not very mechanically apt when it comes to cars in all honesty, so any info would be greatly appreciated. Thanks

[Duncan]

Any possibility you put the pressure and return fuel lines the wrong way around? If the pressure line is connected to the fuel pressure regulator instead of the fuel rail you will get no fuel in the rail when the pump runs

[Chopstick Tuner]

Did you prime it after? 

Having all the fuel out of the rail and lines means it's not just going to fire up first flick of the key. Need to get the pump to prime 3 or 4 times before trying to start. 

Failing that, possibly lines mixed up as Duncan said

[Dose Pipe Sutututu]

I reckon @Duncan is on the money here!

[the_dude]

The lines appear to be in order. Before when I said I popped off the pressure line and no fuel came out- I touched the top line. I popped off the bottom line and fuel did spray out. So I believe fuel is getting to the rail. I primed the pump 10 times before starting and still no luck. I sprayed starter fluid into the throttle body and it started maybe half a second before giving up. I feel like I’m so close!

[Dose Pipe Sutututu]

swap the fuel lines around just for a sanity check

 

ideally this is the order

Fuel tank -> Fuel Pump -> Fuel Filter -> Rail -> Fuel reg -> Fuel dampener -> Fuel tank

[Chopstick Tuner]

On 02/06/2022 at 11:23 PM, the_dude said:

The lines appear to be in order. Before when I said I popped off the pressure line and no fuel came out- I touched the top line. I popped off the bottom line and fuel did spray out. So I believe fuel is getting to the rail. I primed the pump 10 times before starting and still no luck. I sprayed starter fluid into the throttle body and it started maybe half a second before giving up. I feel like I’m so close!

Do as said above just to rule it out. Then next step, if you're confident you have fuel in rail, is see if your injectors have power and if they're clicking at all. 

[the_dude]

On 6/2/2022 at 8:26 PM, Chopstick Tuner said:

Do as said above just to rule it out. Then next step, if you're confident you have fuel in rail, is see if your injectors have power and if they're clicking at all. 

I hear no clicking whatsoever from the injectors. They’re brand new, I double checked all the connections, fuses are good. What else could be causing them not to click?

(injector data if that helps)

[Chopstick Tuner]

On 03/06/2022 at 10:50 PM, the_dude said:

I hear no clicking whatsoever from the injectors. They’re brand new, I double checked all the connections, fuses are good. What else could be causing them not to click?

(injector data if that helps)

Should have a constant 12v supply to the injectors, ecu switches the earth. Not sure how many things could prevent ecu from telling injectors to fire but there's a few

[joshuaho96]

I recommend connecting a diagnostic cable to the ECU and figuring out why it won't fire the injectors.

[the_dude]

Ended up finding this fuse blown, thought that was my issue. Replaced it, tried to start her, still won’t. Switched back to my old injectors, won’t start. Double checked everything I’ve touched, and then some, and then checked again for good measure. Got an engine code reader and all it reads is ERROR. Local shop is too backed up so they can’t touch it. 

I’m completely out of ideas gents. Anything and everything at this point would be greatly appreciated.

[TurboTapin]

On 6/18/2022 at 10:06 AM, the_dude said:

Ended up finding this fuse blown, thought that was my issue. Replaced it, tried to start her, still won’t. Switched back to my old injectors, won’t start. Double checked everything I’ve touched, and then some, and then checked again for good measure. Got an engine code reader and all it reads is ERROR. Local shop is too backed up so they can’t touch it. 

I’m completely out of ideas gents. Anything and everything at this point would be greatly appreciated.

1 - What fuse was that exactly? Missing details here. Might not even be related...

2 - If you're changing injectors, what ecu are you running? 

My train of thought here is for whatever reason you decided to change to 550's and you're still running a stock ecu/tune. If so, 30$ says you're issue is not no fuel, it's too much fuel... and you're engine is flooded. Just pop your sparkplugs out and see if they're wet and check if you have fuel sitting in your cylinders after cranking. This would also explain why it wouldn't start when you went back to the stock 380cc's. 

Edited June 18, 2022 by TurboTapin

[Murray_Calavera]

I have a feeling that if the OP's mechanical skillset is at a point where he thinks its ok to install higher flowing injectors while running a stock ECU, while he stated that 'nothing went wrong', I have a feeling that something did in fact go wrong during the install however his mechanical knowledge didn't allow him to realise that something was not done correctly/was damaged/etc. 

If that is the case, it would probably make the most sense to take the car to a workshop for them to troubleshoot. 

[the_dude]

Not a stock ECU. Its an AEM Infinity 506. The car was tuned on the stock injectors. I installed the new injectors and before starting, had it tuned again to support the new injectors. He did everything correctly (I’m assuming).

[TurboTapin]

On 6/20/2022 at 10:39 AM, the_dude said:

Not a stock ECU. Its an AEM Infinity 506. The car was tuned on the stock injectors. I installed the new injectors and before starting, had it tuned again to support the new injectors. He did everything correctly (I’m assuming).

Pop your sparkplugs out and confirm you're not getting fuel while cranking please. 

Edited June 20, 2022 by TurboTapin

[Chopstick Tuner]

Mate you need to put all the info here so we're not going in circles. 

1) Have you removed plugs to see if there's too much fuel as one of the guys suggested?

2) Have you swapped fuel lines to be sure you're not mixed up as was suggested? No offence but you didn't sound remotely confident they're correct. 

3) Have you checked that you have power at the injectors at all? 

4) What was the fuse that was blown? 

5) Have you contacted the tuner for their input considering they just tuned it and possibly missed something? 

 

Diagnostics requires a lot of ruling things out until you narrow down possibilities, difficult to do with half the information available. 

[GTSBoy]

Are we going to take bets on some sort of blanking caps left on/in the new injectors?

[Dose Pipe Sutututu]

On 21/06/2022 at 9:16 AM, GTSBoy said:

Are we going to take bets on some sort of blanking caps left on/in the new injectors?

or fuel hoses backwards  

hence fuel pump fuse blowing (or I think it's the fuel pump fuse, OP was not specific on which fuse popped)