Need Some Help Diagnosing DTCs
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From: West Lafayette, IN
Need Some Help Diagnosing DTCs Hey Guys,
I know these codes have been discussed in the past, and I have done some research to learn as much about them as I can, but I'd still very much appreciate some specific input as I'm quite unfamiliar with the tuning scene and am preparing to have my car inspected (OBDII only).
Here are the error codes I'm getting:
P0121 - TP Sensor Circuit Insufficient Activity (OLD) (History) (Immature)
P0135 - HO2S Heater Performance Bank 1 Sensor 1 (OLD) (Immature)
P0138 - HO2S Circuit High Voltage Bank 1 Sensor 2 (OLD) (Immature)
P0158 - HO2S Circuit High Voltage Bank 2 Sensor 2 (OLD) (Immature)
P0300 - Engine Misfire Detected (SES) (OLD) (History) (Current) (Immature)
P0442 - Evaporative Emission (EVAP) System Small Leak Detected (SES) (OLD) (History) (Current) (Immature)
P1153 - HO2S Insufficient Switching Bank 2 Sensor 1 (OLD) (Immature)
The two that concern me most are the Sensor 1 codes. My car smells tremendously rich at idle, so much so it actually burns my nose to stand behind it while it's warming up. I'm also not sure what to make of the EVAP code. I'll have to double check my gas cap, but I usually make a point of making sure it clicks several times.
Any and all help is greatly appreciated.
Thanks much,
Josh
I know these codes have been discussed in the past, and I have done some research to learn as much about them as I can, but I'd still very much appreciate some specific input as I'm quite unfamiliar with the tuning scene and am preparing to have my car inspected (OBDII only).
Here are the error codes I'm getting:
P0121 - TP Sensor Circuit Insufficient Activity (OLD) (History) (Immature)
P0135 - HO2S Heater Performance Bank 1 Sensor 1 (OLD) (Immature)
P0138 - HO2S Circuit High Voltage Bank 1 Sensor 2 (OLD) (Immature)
P0158 - HO2S Circuit High Voltage Bank 2 Sensor 2 (OLD) (Immature)
P0300 - Engine Misfire Detected (SES) (OLD) (History) (Current) (Immature)
P0442 - Evaporative Emission (EVAP) System Small Leak Detected (SES) (OLD) (History) (Current) (Immature)
P1153 - HO2S Insufficient Switching Bank 2 Sensor 1 (OLD) (Immature)
The two that concern me most are the Sensor 1 codes. My car smells tremendously rich at idle, so much so it actually burns my nose to stand behind it while it's warming up. I'm also not sure what to make of the EVAP code. I'll have to double check my gas cap, but I usually make a point of making sure it clicks several times.
Any and all help is greatly appreciated.
Thanks much,
Josh
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From: West Lafayette, IN
Yes, the SES light is on. I figured the blinker fluid was to blame. 
The most recent modification was the addition of a Racetronix fuel kit. The Sensor 2, TPS and misfire codes have been on since my first cam install. The EVAP and insufficient switching codes are relatively new.
Would if be helpful if I post my complete mod list? It's available on the Website in my sig, but I can post it for simplicity's sake.
Josh
The most recent modification was the addition of a Racetronix fuel kit. The Sensor 2, TPS and misfire codes have been on since my first cam install. The EVAP and insufficient switching codes are relatively new.
Would if be helpful if I post my complete mod list? It's available on the Website in my sig, but I can post it for simplicity's sake.
Josh
what software do you have to work with or have access to?
I would start by replacing the front o2's, delete the rear o2 codes, and do a CASE/CKP relearn. This should take car of some of the basics and narrow down the trouble shooting.
I would start by replacing the front o2's, delete the rear o2 codes, and do a CASE/CKP relearn. This should take car of some of the basics and narrow down the trouble shooting.
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have you changed anything since then?
If not, you may need to adjust the missfire parameters so it doesn't report duing idle
Edit:
Just double checked... I have my tune set up to not report miss fires (enable temp set to 122*c)
If not, you may need to adjust the missfire parameters so it doesn't report duing idle
Edit:
Just double checked... I have my tune set up to not report miss fires (enable temp set to 122*c)
Last edited by TAQuickness; Aug 24, 2005 at 08:28 PM.
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Verdad Gallardo The rich condition you are smelling is likely due to the O2 sensor codes. When the primary o2 sensors fail, it forces the PCM into the OL table. The stock OL table is a "safe" rich tune to get you back to the dealer with out damaging your engine.
Do you have a WB?
Do you have a WB?
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From: West Lafayette, IN
The fuel pump is the only thing that has been changed since the CASE.
So, setting the Misfire Enable Temp to 122*C will eliminate misfires being reported at idle?
And no, unfortunately I don't have a wideband. Is it safe to assume both the 02s are shot? I have a few logs that are only a month or so old, and on all of them I was pretty rich according to the 02s (mid-to-high 900s, even eclipsing 1000mV a few times).
Josh
So, setting the Misfire Enable Temp to 122*C will eliminate misfires being reported at idle?
And no, unfortunately I don't have a wideband. Is it safe to assume both the 02s are shot? I have a few logs that are only a month or so old, and on all of them I was pretty rich according to the 02s (mid-to-high 900s, even eclipsing 1000mV a few times).
Josh
With a new pump (and maybe regulator, or just even
pushing the regulator harder with a high flow pump
needing blowoff headroom) what do you know about
fuel pressure before & after? I'd look into representing
that properly. Get a reading and adjust the IFR table
based on the flow calculation for the actual working
pressure if it's gone higher than what's in the table
from the new pump.
Headers kill O2s or at least expose their age. If you
want to lean out the open loop tune the Open Loop
Fuel Air table is a good place. But be sure thou art
not deceived, for the road of EFI is beset on all
sides with wickedness and the tyranny of evil
sensors.
Code-setting level of misfires -could- be nuisance
triggering or it could be a desperate cry for help.
Before you kill the codes read the misfire history
and look at current misfires to know whether you
have something worth knowing, going on.
pushing the regulator harder with a high flow pump
needing blowoff headroom) what do you know about
fuel pressure before & after? I'd look into representing
that properly. Get a reading and adjust the IFR table
based on the flow calculation for the actual working
pressure if it's gone higher than what's in the table
from the new pump.
Headers kill O2s or at least expose their age. If you
want to lean out the open loop tune the Open Loop
Fuel Air table is a good place. But be sure thou art
not deceived, for the road of EFI is beset on all
sides with wickedness and the tyranny of evil
sensors.
Code-setting level of misfires -could- be nuisance
triggering or it could be a desperate cry for help.
Before you kill the codes read the misfire history
and look at current misfires to know whether you
have something worth knowing, going on.
As always, Jimmy has offered some great advice/insight.
setting the mis-fire enable temp will eliminate misfire reporting all together. I need to revisit this portion of my tune and determine a better way of doing this. Shop tuners tend to muck up all kinds of things.
setting the mis-fire enable temp will eliminate misfire reporting all together. I need to revisit this portion of my tune and determine a better way of doing this. Shop tuners tend to muck up all kinds of things.
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From: West Lafayette, IN
Thanks so much for all of the assistance, guys.
I haven't changed the tune to compensate for the increased fuel pressure (I went from around 62 PSI at idle to over 70 PSI), so I'll start with that. Is there a formula floating around that will calculate the values I'll need?
What should I look for when examining the misfire log? How can one differentiate between nuisance and serious misfires?
Thanks Again,
Josh
I haven't changed the tune to compensate for the increased fuel pressure (I went from around 62 PSI at idle to over 70 PSI), so I'll start with that. Is there a formula floating around that will calculate the values I'll need?
What should I look for when examining the misfire log? How can one differentiate between nuisance and serious misfires?
Thanks Again,
Josh
