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Subject:Re: Failed Emissions - High HC at Idle
From:OlRivrRat
Date:Fri, 9 Aug 2013 09:06:34 -0600

Scott

        Since your previous Eng was an oil burner your O2Snsrs or Cat may be  
Dirty/Fouled ~ it's my understanding that an overnight soak in  
Gasoline can clean an O2Snsr ~ I'm not sure if a Cat is Cleanable or  
not but it might be worth a try. Also be sure you have GoodConnections  
on the O2Snsr Circuits ~ are you running both Up&DownStream O2Snsrs ~

                                                                                        ORR ~ DeanB

On 9 Aug , 2013, at 1:09 AM, OlRivrRat wrote:

>       According to a 2002 Impreza ServiceManual that I have ~
>
> Idle speed at Park/Neutral position (A/C OFF)                    
> 650(MT)         700(AT)
>
> 650 is where mine idles most of the time with brief dips to 637 &  
> bumps to 662 ~ on very rare occasions
>
> it will do a brief dip 625 ~ Idle is very smooth @ any of those RPMs.
>
>       If you want it to run @ 700 you can alter the ECU to think it  
> is in an A/T ~ My ECU was originally set
>
> for A/T & I switched it to M/T ~ It's a real GasSipper @ 650RPM,  
> only .17GPH on SummerGas.
>
>                                                       ORR ~ DeanB
>
>
> On 7 Aug , 2013, at 9:13 PM, Dennis Haynes wrote:
>
>> Being this is a Subaru engine isn�t the idle electronically  
>> controlled? 650 rpm seems low and that could be part of the  
>> problem. The CO of .15% may indicate a "lean miss fire" condition.  
>> The HC reading 0f 87 at 2,500 rpm is also a problem. I'll bet a new  
>> catalytic converter will take care of both problems. I would do a  
>> compression and leak down test to make sure all is in order, then  
>> look for vacuum leaks or bad injectors. The should be able to check  
>> emissions pre and post the Cat to see if it is working.
>>
>> Dennis
>>
>>
>> -----Original Message-----
>> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On  
>> Behalf Of Gmail
>> Sent: Wednesday, August 7, 2013 12:17 PM
>> To: vanagon@GERRY.VANAGON.COM
>> Subject: Failed Emissions - High HC at Idle
>>
>> Just failed UT emissions with high HC at idle. Strange thing is  
>> this is the exact set up I had before installing a different zero  
>> time rebuild due to the first using too much oil. The only  
>> difference with this new rebuild is the idle is now around 650 rpm  
>> where as the original rebuild idled at 800-900 rpm.
>>
>> I�m wondering if I adjusted the idle back up to the higher numbers  
>> it might pass.
>>
>> Idle       CO2 12.96 �  O2 3.14 �  HC 287 � CO .15
>> 2500     CO2 14.75 �  O2 .47 �    HC 87 �   CO .21
>>
>> Thanks
>>
>> Scott