[s-cars] Misfire Diagnostic Help?

Jim s4 at gates-home.com
Tue Dec 13 13:43:45 PST 2011


Is this only at idle or does it happen at other RPM?  What about under load?  Under boost?

If it's just at idle I'd look at vacuum leaks.

Under load, I'd look at the POS's, ignition wiring, plugs, coil connectors and lastly, the ignition coils.  Any of these things can also cause a stumble at idle but they typically cause increasing problems under load as they degrade.

It's not a bad idea to just replace the POS's at this mileage.  I had one go bad then after another 5,000 miles, the other went bad.  Swapping one cylinder to the spare channel will get you by until you buy a replacement.  I wouldn't leave it like that.  Another channel will fail before long if your luck is like mine.

If it's under boost, look at boost hoses and the wastegate although failure of these results in more than a stumble under boost.  Coils, POS and even fuel pumps can also be a problem under boost.

The frustrating thing is that it can be a combination of things too.  And any one of the typical problems might not end up with the suggested failure point.

If it were me and you haven't already replaced the POS's I'd do that anyway because it's not a big expense, it's easy to do and it will save you going through this again soon.

The suggestion to visit Scott's site and run through his troubleshooting points is good advice.

good luck - BTDT

Jim Gates

On Dec 13, 2011, at 14:00, s-car-list-request at audifans.com wrote:

> Send S-CAR-List mailing list submissions to
>    s-car-list at audifans.com
> 
> To subscribe or unsubscribe via the World Wide Web, visit
>    http://audifans.com/mailman/listinfo/s-car-list
> or, via email, send a message with subject or body 'help' to
>    s-car-list-request at audifans.com
> 
> You can reach the person managing the list at
>    s-car-list-owner at audifans.com
> 
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of S-CAR-List digest..."
> 
> 
> Today's Topics:
> 
>   1. Re:  Misfire Diagnostic Help? (Chris Hemberger)
>   2. Re:  Misfire Diagnostic Help? (Chris Hemberger)
>   3. Re:  Misfire Diagnostic Help (Tom Green)
>   4.  Chapter III from the PBOGF (Pizzo Book of Go Fast) (bill mahoney)
>   5.  Anyone want a set of OEM '92 springs? (docwyte at comcast.net)
> 
> 
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Mon, 12 Dec 2011 15:16:36 -0800 (PST)
> From: Chris Hemberger <cehemberger at sbcglobal.net>
> To: Audionly <audionly at gmail.com>
> Cc: "s-car-list at audifans.com" <s-car-list at audifans.com>
> Subject: Re: [s-cars] Misfire Diagnostic Help?
> Message-ID:
>    <1323731796.11219.YahooMailRC at web180010.mail.gq1.yahoo.com>
> Content-Type: text/plain; charset=iso-8859-1
> 
> Thanks for the suggestion ...??I'll swap-in the OEM ECU as a test.
> 
> 
> 
> 
> ________________________________
> From: Audionly <audionly at gmail.com>
> To: Chris Hemberger <cehemberger at sbcglobal.net>
> Cc: "s-car-list at audifans.com" <s-car-list at audifans.com>
> Sent: Sun, December 11, 2011 11:17:59 PM
> Subject: Re: [s-cars] Misfire Diagnostic Help?
> 
> I have seen that and it was eventually tracked to a bad driver in the ecu,
> 
> Sent from my iPhone
> 
> On Dec 11, 2011, at 7:42 PM, Chris Hemberger <cehemberger at sbcglobal.net> wrote:
> 
>> Hi Folks - have owned my S6 Avant for ~7 yrs & ck the site from time to
>> time; have never posted but the time has come..? My car w/ ~160k has developed 
>> a
>> misfire/rough running condition that I'm looking for some assistance in
>> troubleshooting. Car is stock other than a Stage 1 modded-ECU (MTM as I 
> recall)
>> & has had the Apikol coil-conversion for 3yrs; I'm getting a '4411' code
>> indicating a problem w/ the #1 injector. Swapped coils around (and even tried 
> a
>> new one..), pulled the injector connector and the condition worsens which 
> would
>> indicate the injector is functional to some degree - which leads me to my
>> question: do the injectors experience 'partial' failure which might explain my
>> situation? Selectively disabling each injector on each of the remaining
>> cylinders results in degraded operation. Have run out of diagnostic ideas &
>> thought I'd come to the experts - any suggestions/questions welcomed!
>> Thanks,
>> Chris Hemberger
>> Amston, CT
>> '91 200q Avant
>> '95.5 S6 Avant
>> _______________________________________________
>> S-CAR-List mailing list
>> http://audifans.com/mailman/listinfo/s-car-list
>> http://www.audifans.com/kb/List_information
> 
> 
> ------------------------------
> 
> Message: 2
> Date: Mon, 12 Dec 2011 15:18:51 -0800 (PST)
> From: Chris Hemberger <cehemberger at sbcglobal.net>
> To: theringmeister at triad.rr.com, s-car-list-bounces at audifans.com,
>    S-CAR list <s-car-list at audifans.com>
> Subject: Re: [s-cars] Misfire Diagnostic Help?
> Message-ID: <1323731931.9435.YahooMailRC at web180016.mail.gq1.yahoo.com>
> Content-Type: text/plain; charset=iso-8859-1
> 
> Thanks Wylie - I've already tried the MAF (failed to note that in my post..) 
> with no luck; I'll go do some further trolling & try the ECU.
> 
> Regards,
> Chris
> 
> 
> 
> ________________________________
> From: Wylie Bean <theringmeister at triad.rr.com>
> To: Chris Hemberger <cehemberger at sbcglobal.net>; 
> s-car-list-bounces at audifans.com; S-CAR list <s-car-list at audifans.com>
> Sent: Sun, December 11, 2011 11:33:42 PM
> Subject: Re: [s-cars] Misfire Diagnostic Help?
> 
> Could be lots of things..some of which, such as a dirty connection @ the MAF 
> sensor plug can cause a 4411 code.? I'd check that first as much as anything, 
> and possibly remove and clean the MAF sensor itself if you haven't done that in 
> a while.? It could be the injector but if it's running worse when you unplug it 
> I'd rule out false positives... Check the FAQ on the QW UR-S car forums, and 
> search 4411. There are tons of threads on misfires and the usual suspects come 
> up repeatedly as culprits. The ECU related issues usually manifest themselves as 
> "hiccups" (I had one myself) as opposed to rough running.
> Keep us posted.
> Wylie Bean
> 90 cq
> 91 90q20v
> 92 UrS4
> 08 Q7
> 
> -----Original Message-----
> From: Chris Hemberger <cehemberger at sbcglobal.net>
> Sender: s-car-list-bounces at audifans.com
> Date: Sun, 11 Dec 2011 18:42:15 
> To: <s-car-list at audifans.com>
> Subject: [s-cars] Misfire Diagnostic Help?
> 
> Hi Folks - have owned my S6 Avant for ~7 yrs & ck the site from time to 
> time;?have never posted but the time has come..? My car?w/ ~160k has developed a 
> 
> misfire/rough running condition that I'm looking for some assistance in 
> troubleshooting. Car is stock other than a Stage 1 modded-ECU (MTM as I recall) 
> & has had the Apikol coil-conversion for 3yrs; I'm getting a '4411' code 
> indicating a problem w/ the #1 injector. Swapped coils around (and even tried a 
> new one..), pulled the injector connector and the condition worsens which would 
> indicate the injector is functional to some degree?- which leads me to my 
> question: do the injectors experience 'partial' failure which might explain my 
> situation??Selectively disabling each injector on each of?the remaining 
> cylinders?results in degraded operation. Have run out of diagnostic ideas & 
> thought I'd come to the experts - any suggestions/questions welcomed!
> Thanks,
> Chris Hemberger
> Amston, CT
> '91 200q Avant
> '95.5 S6 Avant
> _______________________________________________
> S-CAR-List mailing list
> http://audifans.com/mailman/listinfo/s-car-list 
> http://www.audifans.com/kb/List_information 
> 
> 
> ------------------------------
> 
> Message: 3
> Date: Mon, 12 Dec 2011 18:50:17 -0500
> From: Tom Green <trgreen at comcast.net>
> To: s-car list <s-car-list at audifans.com>, cehemberger at sbcglobal.net
> Subject: Re: [s-cars] Misfire Diagnostic Help
> Message-ID: <19680EF5-E1A1-4CF1-AB90-28787AC654D4 at comcast.net>
> Content-Type: text/plain;    charset=US-ASCII;    format=flowed;    delsp=yes
> 
> I don't know that I can point you directly at a solution, Chris, but  
> perhaps you will stumble on it.  You probably know about Scott  
> Mockery's business web site <http://www.sjmautotechnik.com/> since it  
> is the most common source for learning blink codes.  If not, shame on  
> you, go there now.  Anytime you read codes, clear them after recording  
> them.  You did not mention the CEL or MIL  as Audi names it.  You  
> should run the output tests to check that the injector functions  
> electrically.  Your post reads like you are doing most of your own  
> maintenance.  As Wyley suggested, clean the MAF connector plug and see  
> that the MAF and air intake are clean also.  Deoxit from Radio Shack  
> or online at Caig Labs is a good electrical cleaner/enhancer and  
> cheaper than Stabilant 22.  Swab the injector connectors also with  
> some of those electronic store swabs with the little ends.
> 
> It would probably not be a waste of money to have the injectors  
> cleaned/tested by one of the well-known shops.  <http://www.rceng.com/ 
>>    <http://www.mrinjector.us/> , or  <http://fuelinjectorconnection.com/shop/ 
>>   come to mind, but a local shop could work.    It would be nice  
> to know the fuel pressure, but maybe not essential  yet.
> 
> Since you are still blinking after 7 years or more with the 200/20v,  
> you must not need this information often.  You are missing out on some  
> information stored by the fault code that you simply cannot read with  
> the blink code.  The VAG-COM software is available free in the Lite  
> version that works very well with these cars.  All you need is a  
> windows laptop running windows XP maybe (you don't want to be too new,  
> I don't think, but the ross-tech.com web site has details on that, I  
> believe)  Then, you can buy one of those cheap cables on ebay and the  
> 2X2 adapter available there also.  These will run the lite version for  
> free or registered for $99.  Either is fine, but will make diagnosis  
> so much easier, and reset your service codes as well.
> 
> Wylie mentioned quattroworld.com UrS4/6 forums for help and a great  
> FAQ also.  There are several posters in CT on that forum also-some in- 
> person help beats this long distance stuff every time.  Someone local  
> might just have a few spare parts to help diagnosis along as well.
> 
> 
> Tom '95 S6
>          '95.5 S6 avant
> Knoxville, TN
> 
> 
> On Sunday December 11, 2011, at 6:42 PM,  Chris Hemberger <cehemberger at sbcglobal.net 
>> wrote:
> 
>> Hi Folks - have owned my S6 Avant for ~7 yrs & ck the site from time  
>> to
>> time;?have never posted but the time has come..? My car?w/ ~160k has  
>> developed a
>> misfire/rough running condition that I'm looking for some assistance  
>> in
>> troubleshooting. Car is stock other than a Stage 1 modded-ECU (MTM  
>> as I recall)
>> & has had the Apikol coil-conversion for 3yrs; I'm getting a '4411'  
>> code
>> indicating a problem w/ the #1 injector. Swapped coils around (and  
>> even tried a
>> new one..), pulled the injector connector and the condition worsens  
>> which would
>> indicate the injector is functional to some degree?- which leads me  
>> to my
>> question: do the injectors experience 'partial' failure which might  
>> explain my
>> situation??Selectively disabling each injector on each of?the  
>> remaining
>> cylinders?results in degraded operation. Have run out of diagnostic  
>> ideas &
>> thought I'd come to the experts - any suggestions/questions welcomed!
>> Thanks,
>> Chris Hemberger
>> Amston, CT
>> '91 200q Avant
>> '95.5 S6 Avant
> 
> 
> 
> 
> 
> 
> ------------------------------
> 
> Message: 4
> Date: Mon, 12 Dec 2011 23:26:18 -0600
> From: bill mahoney <airbil at gmail.com>
> To: s-car-list at audifans.com
> Subject: [s-cars] Chapter III from the PBOGF (Pizzo Book of Go Fast)
> Message-ID:
>    <CAO9xvqywbBSi-wmdr3Hs8Ft_C6PFBYVAs7wjO18XcAQnWOd=fQ at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
> 
> http://img.photobucket.com/albums/v101/Mikes72sb/Hershey%2007/DSC00096.jpg
> 
> Bill~BTDTx100~m
> 
> 
> ------------------------------
> 
> Message: 5
> Date: Tue, 13 Dec 2011 15:40:33 +0000 (UTC)
> From: docwyte at comcast.net
> To: Audi List <s-car-list at audifans.com>
> Subject: [s-cars] Anyone want a set of OEM '92 springs?
> Message-ID:
>    <1811122017.998253.1323790833028.JavaMail.root at sz0113a.emeryville.ca.mail.comcast.net>
>    
> Content-Type: text/plain; charset=utf-8
> 
> In great shape, approximately 85k miles on them. 
> 
> $250 plus shipping/paypal fees takes em. 
> 
> 
> ------------------------------
> 
> _______________________________________________
> S-CAR-List mailing list
> S-CAR-List at audifans.com
> http://audifans.com/mailman/listinfo/s-car-list
> 
> 
> End of S-CAR-List Digest, Vol 98, Issue 12
> ******************************************
> 


More information about the S-CAR-List mailing list