Jump to content
SAU Community

Advice Please - Injectors and Tune Issue


Recommended Posts

Advice Please - Injectors and Tune Issue

Hey guys. 

I've been getting parts together for a couple months and finally installed them into my R33. I got the following installed:

 

-Hypergear G3 21U high flow

- z32 AFM and stainless intake pipe

- Walbro 255lph fuel pump

- 550cc Injectors (STI side feeds, part # 16600-AA170 with harnesses)

- Nistune ECU

- 3in turbo-back stainless exhaust and Blitz FMIC already installed  

 

Along with the parts I also did all the maintenance items, got new NGK coppers gapped to 8mm, new fuel filter etc etc. However, when I got Toshi to try and tune my car, he claimed that the AFRs were being whack and it was misfiring at 5k rpm. I immediately thought of coils and I also didn't do the earthing mod for the fuel pump, so this might have been my issue. 

I ended up buying Yellow Jacket coils packs and I also earthed the fuel pump and checked to ensure full voltage. The car started fine, test drive fine low revs, etc. However, again getting Toshi to try and tune and check AFRs etc and we still can't run boost into it as he claims the AFRs are still unstable. He now says it's the Injectors but I don't know if I believe that as when we're in the "base" tune he did, the car isles fine, revs fine etc albeit a bit rich. 

 

In short, 2 questions:

1. I know there are better options, but how likely is it these Injectors are actually the issue? They're not high flowed, but genuine STI Injectors. Anyone else run these? I can send back under warranty if needed.

2. How likely is it that the tune is the issue? I read another thread on here where someone had a problem with a Toshi tune that came down to injector latency being set wrong and another tuner fixed it. 

I really feel feel like after all the work done, and the fact that a rich tune revs fine but another tune doesn't makes me think it's the tune? Anyway, I currently am advised by Toshi not to boost the car as the AFRs are off and he wants me to replace Injectors and go back to him. I just want other opinions. 

 

Sorry for essay. Thanks in advance. 

Edited by inmaniac
Link to comment
Share on other sites

The very, very first step when diagnosing this shit is to put a fuel pressure gauge onto it and see what that is doing under load.  It is cheap (free) and it takes 90 seconds to do.  Speculating about the health of injectors is a waste of time before knowing this one fact.

Yellow Jackets are also famously variable in their quality.  Any set of 6 might be fine, but any one of them might be f**ked from the factory.  Ergo, they are a waste of time and money.

Link to comment
Share on other sites

Thanks for the replies guys.

The injectors are remanufactured but have been tested and all ok (got the paper at home).

I haven't checked fuel pressure so I may have to do this.

Johnny (above) is going to have a crack at tuning for me, cheers mate!

Link to comment
Share on other sites

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
 Share



  • Similar Content

  • Latest Posts

    • Much less twat-tastic. CF wheels are too garish for civilised use.
    • From there, as the manual says....assembly is the reverse of disassembly, no tricks worth mentioning Much better (for me)
    • In my case, the standard wheel I had was in good condition but the buttons had more wear, so I swapped them across from the original wheel from the car. The plastic rear cover is held on by 4 tabs, and once the wiring is removed you can get access to 2 screws on each side the hold the buttons in From there I just swapped the wiring over. What was interesting is the standard style wheel is 2.0kg but the carbon fibre one is 50% heavier at 2.9kg. It even has a weight inside the wheel at the top to make up for some sort of imbalance in the design. weird
    • Once the airbag is off, to remove the steering wheel.... Undo the 2 plugs into the clock spring, and the horn connector from it's clip. Hit the 19mm nut with a rattle gun (preferably) or if you don't' have one, you probably want an assistant to hold the wheel in place while you use a breaker bar to undo the nut Then, screw the nut back on 3 turns, and pull the wheel sharply towards you. If that doesn't work hit it medium force with a rubber mallet on either side, or possible behind if you can get there. If that all fails (it shouldn't!) you might need a steering wheel puller
    • So, to next task....the carbon fibre steering wheel was either an expensive factory option or a chinesium special. Either way, I don't like either the flat bottom or thick ring style, so it had to go So...to remove the steering wheel.... First, disconnect battery negative and stomp on the brake pedal for a few seconds. Then, remove the small circular covers on each side of the wheel's rear surround to uncover the airbag clips. You need to push something like a flat bladed screw driver through, to push the steel clip inwards and pull the side of the airbag forward. Once you've done the easy side, same on the centre console side. You can see the tab you are shooting for circled in red Then, disconnect the horn spade connector and for the yellow airbag plug you need to get something small under the black locking tab to pop it out, then the connector releases......airbag is off  
×
×
  • Create New...