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2000 Honda Civic Si Question: Mil code P0172 and P0170, running too rich

 

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lude22r, 1.6L 4 Cylinder, Clovis, CA, July 21, 2012, 23:41
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 Technician

I have a b18c swap in a honda civic, this swap is ref'd and all i need is a smog check to register it yet the cel light wont go away.

I have replaced;
fuel filter
both oxygen sensor 1 and 2
cap and rotor

i borrowed a scanner and the manifold absolute pressure sensor reading averages between 7.4-8.9
the throttle position sensor is 9.4% at idle
engine coolant temperature sensor ranges up to 184F and then the fan kicks on
intake air temperature sensor ranges between 60F(idle)-110F
Also i had the valve clearances checked and they were fine
I inspected the injectors and resistance is 12.2-12.3 OHM's
Also this car has a fuel pressure gauge on the fuel filter, and it reads normal (51psi @ idle)

Thank you

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  • Answer #1

    ziptie12 July 25, 2012, 09:42
     Master

    What other mods do you have that would affect it's breathing(air-fuel ratio). Check fuel pressure REGULATOR . If the rad fan(s) kick on and the engine temp is truely only 184F ,, then your running cool , should be up around 210-215 that it kicks on. Do you have an infra-red thermometer to check various points on engine to see what it's doing? Have you tried a good old-fashioned vacuum guage at the manifold? remember 'old-school taught the new school'. Also want to make sure the cat's close enough to engine to heat up properly.

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    lude22r, July 25, 2012, 18:02
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     Technician

    You Ziptie12 are a genius I thank you very much for your input. I will look into the fuel regulator and the cooling fan switch. Two things I oversaw.

    Other modifications: Cold air intake, skunk2 manifold, dc head, high-flow catalytic converter, racing thermostat & radiator.

    Yet I believe you are on the right track, thanks again and I will let you know if this annoying problem gets resolved.

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    ziptie12, July 25, 2012, 22:57
     Master

    Please do , I'd be amazed if I was actually of any help. Thanks.///////////////////////////////////////////////////////////Stupid question this late (8/1) but if it hasn't passed the smog check yet ,I was wondering about the PCM itself .

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    lude22r, October 08, 2012, 19:14
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     Technician

    Turned out to be the injectors but the fan switch was bad aswell.

    Thanks again

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