PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Throwing P0135 and P0300 codes

Old Mar 14, 2005 | 10:30 PM
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Default Throwing P0135 and P0300 codes

H P0135 HO2S Heater Performance Bank 1 Sensor 1
H P0300 Engine Misfire Detected

Okay so I have a Procharger, full exhaust(FLPs), 6.0L heads, mild blower cam, stock descreened MAF, in-car wideband, etc. So I thought I was throwing codes just for an EVAP leak which i was aware of. Well when I checked today I had the evap leak along with 135 and 300. So my wideband is telling me that i'm running extremely rich at WOT. But it seems to bounce around 14.7:1 when just cruisin around. So could I have fouled out the plugs in just 6 months(keeping in mind i don't drive it but a few times in the winter)? Could this cause a problem with the O2s? Are these two codes completely seperate? Is the misfire being cause by something else?

Thanks for any help you guys can give.

Mike
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Old Mar 15, 2005 | 01:41 PM
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What are you misfire setting at? Have you raised them to allow for the additional valve train noise from the cam? Have you logged to see if there is any pattern or particular cylinders that are at fault. I got a P0300 when I did my cam, springs, and pushrods. I just raised the misfire tables to 32000 and swapped plug wires to be safe.
Im not sure about the other code. Im sure others here will be able to give you a quick fix for that.
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Old Mar 15, 2005 | 02:02 PM
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Originally Posted by greentahoe
What are you misfire setting at? Have you raised them to allow for the additional valve train noise from the cam? Have you logged to see if there is any pattern or particular cylinders that are at fault. I got a P0300 when I did my cam, springs, and pushrods. I just raised the misfire tables to 32000 and swapped plug wires to be safe.
Im not sure about the other code. Im sure others here will be able to give you a quick fix for that.
I made no adjustments for the cam, tuning wise. I will have to monitor the misfire levels. Thanks for the advice. I was thinking running rich was fouling out my plugs. This is a different angle I will have to check out.

Mike
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Old Mar 15, 2005 | 03:20 PM
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Originally Posted by buschman
I made no adjustments for the cam, tuning wise. I will have to monitor the misfire levels. Thanks for the advice. I was thinking running rich was fouling out my plugs. This is a different angle I will have to check out.

Mike
What software are you using?
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Old Mar 15, 2005 | 04:31 PM
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Originally Posted by greentahoe
What software are you using?
Edit for now. A friend is trying to talk me into tuner. I might upgrade when 2.0 USB comes out.

Mike
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