Damn P 170

[werx]

I'm trying to pass emissions but the car keeps throwing a P170 code: fuel trim Malfunction. I'm not sure which way to go to fix the problem. I'm running stock injectors but I've installed a walbro 255 fuel pump and have 6AN line running from the fuel filter to the fuel rail. I'm also running a Fuel Lab AFPR adjusted to 42.5. I have a 2G Eagle Talon AWD with 6bolt swap and JDM Cyclone intake.

 

[gofast63]

O2 housing leak or a faulty o2

 

[werx]

i replaced the upstream o2 sensor and it thru the code even faster!

 

[curt-s]

Assuming you set the pressure correctly, faulty gauge on the AFPR? Have you watched your O2 cycles?

 

[shakeandbake]

Im just gonna state it so its out there. But boost leaks cause this. Has this been a constant code?

 

[werx]

If it's a boost leak it's not in the usual places (silicone couplers, intercooler, MAF etc..). I think it's coming from the throttle body but I'm not sure how to test for it. Then again it maybe the gauge. I conveniently have a spare so I try that.

 

[Diamond Star Werks]

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[DOUBLEPOST=1415161908][/DOUBLEPOST]Try the diag chart. Did you check you o2 operation before replacing it? What exactly are you fuel trims? 0 never changing? way positive? way Negative?

 

[Calan]

If it's a boost leak it's not in the usual places (silicone couplers, intercooler, MAF etc..). I think it's coming from the throttle body but I'm not sure how to test for it. Then again it maybe the gauge. I conveniently have a spare so I try that.

The throttle body is a usual place for a boost leak. If you are testing it properly, it will show up there (usually around the shaft seals) as easily as it will anywhere else.

 

[mercaholik]

Wait you have a 2g with 6 bolt swap so do you have your barometric sensor hired up? The 2g ecu will be looking for it and in mjcanada's post it shows failed baro as a possible cause for the code. And the throttle body has a couple of places to leak, shaft seals, isc gasket, biss screw and o-ring, fiav gasket. Do you have a stock 2g ecu and a way to log and tune?

 

[werx]

Sorry it took so long to reply. So let's start at the top. Yes I have a stock 96 ECU, I fixed the code by reworking the EGR valve... Code went away but it's now throwing up a P1105. Found out that's a fuel pressure solenoid malfunction. Needless to say, I bought a new solenoid. Between the new solenoid and tightening all hose connected to the fuel pressure solenoid, I hope to finally be done with all these B&%%$@!t emission codes

 

[werx]

Well it fixed the P1105 problem but I come to find out that my 96 Mitsubishi ECU will never pass emissions because of a programing flaw in the ECU. My city's emission czar won't exempt me from emissions because there was a recall almost 15 yrs ago. So I'm in the process of getting a flashable ecu from another year.