2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

fuel cut question

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Old May 21, 2010 | 07:46 PM
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fuel cut question

I'm hitting fuel cut and am wondering what is causing it. I am completely stock but I have removed all my emmissions stuff. I have an 87 TII
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Old May 21, 2010 | 10:15 PM
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intake? gutted cats? exhaust?
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Old May 22, 2010 | 12:40 AM
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everything in 100% stock except emissions removal and I am hitting fuel cut at 5500 rpm. would emissions removal cause this? or could it be old plugs and wires not igniting all the fuel and the o2 sensor is reading rich and causing fuel cut ? these are the only two possible things I can think of.

I unplugged the boost sensor and it stopped it from happening

I also want to know how safe it is to run a FCD since my wastegate isn't ported and I don't want to boostcreep and blow my engine
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Old May 22, 2010 | 03:34 AM
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FCD's are safe to run. You should get one.

It almost sounds like you botched something in your emissions removal + hooked the line up wrong to your boost sensor.
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Old May 22, 2010 | 10:00 AM
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Yeah, you can definitely run an FCD if you're staying stock. As soon as you get a free flowing exhaust, invest in making your wastegate bigger as you will get some bad boost creep if you don't. You most likely won't see any boost creep without any mods though.
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Old May 22, 2010 | 12:49 PM
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brap-brap-brap
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^ +1

and get a decent boost gauge.
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Old Jun 3, 2010 | 10:53 PM
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bump any other options like would not havin a restrictor pill cause this?
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Old Jun 3, 2010 | 10:57 PM
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No, a restrictor pill just smooths out pressure changes. The S4 wastegate is TINY, so it doesn't surprise me that a stock car could potentially hit fuel cut.
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Old Jun 3, 2010 | 11:34 PM
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Originally Posted by barnett87rx7
everything in 100% stock except emissions removal
so what EXACTLY did you remove from the emissions? also, your car is no longer stock.
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Old Jun 4, 2010 | 12:04 AM
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When I got my 87 TII I couldn't rev past 6500RPM due to a faulty TPS (throttle position sensor), you might check that out. If not by replacing it with a known working or new one you'll need to test it with an analog meter so you can accurately check the sweep of the resistance (I never could get that to work right, but it might be because I had a super cheap meter).
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Old Jun 4, 2010 | 12:29 AM
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if you did anything that frees up how the turbo breathes, intake or exhaust (ex. removed or gutted catalytic converters), you will start to develop boost creep because the stock internal wastegates cannot accommodate the additional flow. Fuel cut kicks in ~8.6psi boost.

Just throw on a FCD and aftermarket boost gauge.
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Old Jun 4, 2010 | 01:51 AM
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Originally Posted by barnett87rx7
I unplugged the boost sensor and it stopped it from happening
Sorry I missed this part. Could be fuel cut due to boost creep. Is it cutting out at low throttle but still right at 5500RPM? If so I'm still thinking TPS.
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Old Jun 5, 2010 | 10:08 PM
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I found a hole in the exhaust were the downpipe connects with the rest of the exhaust because there is no gasket could this cause it??
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