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Need Help! Fuel Cut In My S15

boosted_32

By boosted_32,
in Engines & Forced Induction

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boosted_32 Proficient

boosted_32

Posted
Posted

OK this post is directed at s15 owners, I have just put a few mods on my s15 including a boost controller and when I wind the boost up and give the car a squirt it sounds like the engine cuts in and out, I have been told this is the fuel cut defence system in the standard ecu which momentarily shuts the fuel system down when you try run more then standard boost that the ecu is set to. If this has happened to you in your s15 plz tell me how you solved this problem thanks

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https://www.sau.com.au/forums/topic/125930-need-help-fuel-cut-in-my-s15/
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sinistaGTR Grand Master

sinistaGTR

Posted
Posted

yeh its that, do a search......

also if you look at nissansilvia.com they will be a lot more specific to your car. i mean were all a friendly bunch here lol, jus if you get a problem thats really specific to the sr20 or s15 they will be able to help you out bucket loads.

nfi Community Regular

nfi

Posted
Posted

I have an s15. Fuel cut from boost is not an issue on s15 with the boost levels you should be running.

On the dyno mine saw 18psi with stock ecu very briefly and there was no boost cut.

With standard ecu I would not run any more than 11psi as the ecu in s15 makes the midrange REALLY lean. Do you have a boost guage to determine what boost you have set? Once you have power fc I wouldn't run more than 17psi. I only run 16.

If you can, don't do any boost tuning yourself if your new to this its a really bad idea. Do it on the dyno. A rebuild will cost you more than $4k to do it properly.

The problem you currently have will either be massive boost ie. >20psi or more than likely the spark blowing out. Gap the plugs correctly. If you don't know what to set them to take the car to a workshop.

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

He is right though.

Whilst its a Nissan, i couldnt tell you the first thing about an SR, what problems are common to them or anything.

Obviously the basic things like AFM/plugs/coils... but apart from that i couldnt even tell you if the coils are a usual suspect on the SR like they are on the RB...

mad082 Grand Master

mad082

Posted
Posted

i think it may be a coil issue. i degreased my motor last night, and despite my best efforts 1 of my coils got rather wet (the rag i had covering it got caught on the hose and pulled it out of the road a little bit). anyway after i finished i took the car for a drive. once it had warmed up i got into it a bit and at about 3500rpm (once boost had come on fully) it was dropping a cylinder due to it shorting out. it just sounded like the speed limiter, but it would keep reving. i kept driving normally for a while and it went away once the coil fully dried out, and wasn't there when i drove today.

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