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Over Fueling Stock S1 25

skitzone80b

By skitzone80b,
in Engines & Forced Induction

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skitzone80b Explorer

skitzone80b

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Hey guys hope you don't mind first post being a question been asking on 31 club but haven't had a lot of replies. I've recently installed a series 1 25 into my 31.

109,000 kms on engine

Redtop J pipe (no bov)

2.5 fmic way to big.

standard dump, de-cat and 3" blast pipes.

GFB boost controller set at 8 psi

Bosch 040 pump

As you can see it's stock. I have checked all the vacuum lines and swapped the j pipe because I thought the spring in the bov was gone and leaking. I've checked all silicone joiners. I have a boost gauge hooked up in the engine bay to help with diagnostics, no boost spiking or drop so I'd have to say it doesn't have a vacuum leak. I've changed the afm out with a couple others took a lot of the missing away but not completely. I've tried screwing the icv all the way in as well as unplugging it to see if that was the issue. I've tried adjusting the tps and put it back to where it originally was.

Now when you start it it'll idle for a few seconds at 500 then raise and settle to a thousand rpm. Between 1000 and 2000 rpm it has a slight hesitation, car will drop revs below idle when you back off the throttle. Anything over 2000rpm when you back off throttle if you don't blip it the car will completely stall. Even if you're doing 5 grand in 4th... I'm really stuck here and getting a little bit over everything if I'm honest I'd just look to put some km's on it.

If anyone has any ideas please let me know anything else to add to the list to check, and a few tips on how to check it would be amazing.

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https://www.sau.com.au/forums/topic/411518-over-fueling-stock-s1-25/
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skitzone80b Explorer

skitzone80b

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Where are u located? Take it to a tuner and get it checked. Can be many possibilities

In perth 40km's from the closest tuner don't wanna drive it don't really want it to be trailered and left at a shop with an open bill. Rb25 only went in it after a 20 had spent 4 months at a professional shop that couldn't get it running. And I was left with the bill. I'm running out of money, I'm running out of patience and a shop is a last resort but I was just wanting a bit of a checklist to try from home.

skitzone80b Explorer

skitzone80b

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The rb20 stopped fueling all of a sudden had pressure at the rail had signal going to the injectors but the injectors would pulse random amounts at different injectors and not in sequence.

Tried 3 differents AFMs

Tried 2 different ECU's

All sensors are RB25.

How do I do an ecu diagnostic?

DVS JEZ Grand Master

DVS JEZ

Posted
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I use my consult. But there is a way to test via engine light afaik. Cant help u on how to tho as i dont use it that way.

So u have rb25 with ALL sensors including tps, knock and afm? With rb25 loom and ecu?

Are u running stock fuel pressure reg?

Have u tried disconnecting 02 sensor and driving?

Are u running stock intake pipe to afm?

skitzone80b Explorer

skitzone80b

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Thanks WMDC I'll have a look bud.

RB25 series 1 stock ecu and loom has knock sensors installed I'm assuming they're 25 to match the ecu? I have sexy fingers when it comes to electrics so the boys sorted it out for me. Running stock fuel pressure reg at the moment waiting til pay day to buy a nismo non rising rate set n forget incase the 040's pushing past the stock regulator. All my diagnostic stuff is for carby so can't check the fuel pressure yet. disconnected the 02 sensor and just had it stationary and it was doing all the same things, will it be different under load?

skitzone80b Explorer

skitzone80b

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Errr cheers for the link saved it. Homeboy who wired it will bell me after work I'll ask him if he kept the consult in the wiring assuming he did and whether it would work with the check engine light on the dash of the 31. I thought they had an led on the side of the ecu that flashed.

And to the reg fair enough, I saw that it was about $100 to buy an inline efi gauge or $199 for a regulator with a gauge so I was going to buy the reg with gauge. I'll see if I can get the diagnostics checked out n see what it says. If it doesn't work on the dash can I plug an ODBII reader into it anywhere? I know my friend owns one.

KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

No early Nissans are not OBDI or II. You need something like the ecutalk cable (or buy the display if you haven't got a laptop):

http://www.ecutalk.com/

In my Stagea the consult plug is behind the coin tray next to the fusebox.

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