Jump to content
SAU Community

Recommended Posts

Hey guys, don't post on here much (if at all), but i hope u can still help. I searched, i didn't find.

Didnt know if this should go in forced induction or n/a forum, since its got aspects of both... There should be an electrical/ecu subforum.

Basically, my friend has gone and purchased pretty much everything he needs to turbocharge his n/a S1 R33 (1993) off these forums (bar dump pipe, which he is getting tomorrow). We swapped the injectors and ecu over and now his car wont start. Everything is connected the way it was before and it doesn't sound like the fuel pump is priming, so that would be my first guess.

All the turbo parts (bar intercooler piping, which isn't attached) are off the same car, which was running at the time the parts were removed but I'm not sure if the car was an S1 or an S2.

So, basically, is there any reason why a S1 RB25DE R33 running just the ecu and injectors from a RB25DET R33 wont start, remembering it may possibly be s2 ecu? Is there any wiring/control differences in the fuel pump/ecu circuits, or could the ecu just be a dud?

Only mods to his car are pod filter, exhaust, steering wheel, rims and springs, so none of these should be making the difference.

EDIT: He got the turbo bits off "R34GTFOUR" so if you could reply stating if S1 or S2, I was the one who said I would be putting it together :P

Edited by Mitchd03

The pump should still work, the only difference is a relay for upping the voltage to it under load, that doesn't come into effect at idle.

Where is the AFM hooked up? You need a closed system so the air goes through it and gives a reference voltage for the ECU.

Also has he got the turbo fuel pump fitted? He'll run into dramas with it leaning out if it's not already in.

Yep grab a GTSt pump and fuel regulator (or did you get the complete injectors and rail?) if you can...but saying that, your car isn't starting for another reason....as it will still idle on a GTS pump just fine

Well all we did last night was remove fuel rail and insert the new GTST injectors and then plug in the GTST Ecu, is it possible we need to reset the settings by unconnecting the battery? Could it also be something to do with a fuse?

Ok, it starts and idles now, but it blows light grey smoke, and misfires. Smells like there's no catalytic converter.

Could this be wrong fuel pressure for the turbo ecu? If so, what is the correct fuel pressure, as we are using an N/A fuel press reg.

Remember, its an RB25DE with T injectors and ecu.

EDIT: Just took it for a drive and its definitely running way too rich, the cat light came on when taking it to higher (4-5k) revs, huge exhaust pops when shifting gears, hunting for idle etc. but the misfiring got better (wasn't cured) at higher rpm (around 3)

Stuck injector? Wrong fuel pressure? Fuel pump? (remember, NO BOOST, its still an n/a, no more air than before, therefore no more fuel needed, so pump should be capable for now)

Edited by Kyro

why are you installing injectors before the turbo.... the ecu is tuned to run the injectors with the forced induction, all the problems you have are the sign of over fueling, if you's keep running it u'll burn out the cat (thats why the light is coming on, it's getting to hot), install all the components needed Turbo, intercooler, pump, FPR...

why are you installing injectors before the turbo.... the ecu is tuned to run the injectors with the forced induction, all the problems you have are the sign of over fueling, if you's keep running it u'll burn out the cat (thats why the light is coming on, it's getting to hot), install all the components needed Turbo, intercooler, pump, FPR...

The ecu adds fuel as the AFM reads more air, if the ecu just smashed more fuel in all the time, the car would be rich (like this) when not under boost, then stoich when boost hit

You can have a turbocharged car with ecu and injectors designed to run boost, remove the turbo and it will run fine.

I know this is true, i've done it twice. One time to my ford Telstar TX5 turbo. It uses an air flow meter, just like nissan use. The only difference is the tx5 has one massive injector instead of smaller ones on each cylinder (like a carbie). The turbo blew an oil seal, i pulled turbo out, reconnected the afm and it runs fine, its just really slow and loud.

The second time to my z31 300zx. It was a VG30E, naturally aspirated. I had turbo injectors and a turbo ecu lying around, waiting to get a turbo. I had to pull the intake manifold off, so i changed injectors and ecu at the same time. The car runs exactly the same as it did before (misfiring, a little rich, hunts at idle, backfiring on overrun, it's always done this, its an '84 model car). Old injectors were ~180cc, new ones are 269cc (they sound tiny i know, but higher fuel pressure than RB25DE) and the ecu is calibrated to those injectors. We did exactly what i did to the zed, yet i got a completely different result, and my assumption was the fuel pressure regulator, as with the RB swap we kept the n/a fuel pressure reg, but on my VG30E I swapped the regulator with the turbo one (as i got a complete rail).

And now that an N/A ecu is running bigger Turbo injectors, when the turbo ecu couldn't run them... it doesn't make sense. If you put big injectors in the car goes really rich, anyone who has tuned a car should know this. You then have to shorten the injector times to get it to run stoich again, which is what the turbo ecu does.

Bah!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • You very likely need to get it on a dyno and tune it. My assumption is, you've got an RB25DET tune in it, which has a different manifold, different injectors, and different cams as a minimum. What O2 sensor are you running?   When you say it runs extremely rich from idle all the way to redline, is this just free revving it you see that?
    • I seem to the be only person that is using a Haltech 2500 on an NA motor, I've installed a Bosch DBW throttle body to the OEM intake manifold and am having problems maintaining AFR even with the wideband o2.  It will run extremely rich at idle and up to redline, but under load it will go extremely lean in the 20s and i'm essentially having to rev it over 4k and feather the clutch to get it up to speed.  I've read a few other threads of about the butterfly, it seems removing the vacuum to it is supposed to have it remain open, i've noticed no difference under 4k with the vacuum line to it plugged.  I'm hoping someone here has had luck using the NA manifold with Haltech, and if they happen to have a tune for it.  
    • I don't know any details, but I really wouldn't be surprised if they do it as a LHD only version, at least initially.
    • Thanks for the replies everyone. Definitely a coolant push. Oil catch can is empty and always has been. As the engine is out now I'll be having a good look over things. I do have some detonation on the piston tops from a trigger issue back about 5 years ago. I felt it and shut off then bought a new ecu and changed the trigger. Never been an issue since. It never hurt the power, its made almost 80hp more since that incident but I will pull the bearing caps to take a look. If the bearings are damaged I will do a bottom end refresh. Head is being re conditioned at the moment and the block will be cleaned and checked to ensure it's flat. I'll go with a kameari gasket and see how it ends up. The other thing I'm not super keen on is the cylinder colours. I suspect this is from the inlet manifold. The plan will be to put it back together, retune and then stick a plazmaman billet inlet on it and retune. I'm happy with the power, if it makes a little more, then great, but I would rather just make everything more efficient at this stage.
    • Maybe they'll look to do a bunch of presales to help inject some cash fast for their financial issues...
×
×
  • Create New...