misfire under light load

[200q 20v]

Chris,

Looks like misfire starts with higher boost regardless of RPM and only
near or at normal operating temperature. Absolutely absent when engine
is cold.

I believe denser mixture requires higher spark voltage. If there is a
leak the spark will fire elsewhere. My mechanic suggested spraying water
on all spark wires to facilitate and locate the leak. However the
weather is not cooperating right now.

Eugene.

-----Original Message-----
From: chris gregg <loxxrider at yahoo.com>
Reply-to: chris gregg <loxxrider at yahoo.com>
To: 200q20v at audifans.com <200q20v at audifans.com>
Subject: Re: 200q20v Digest, Vol 98, Issue 7
Date: Sat, 21 Jan 2012 12:20:04 -0800 (PST)

Eugene, 


Is it missing under heavy load as well? If not, then I wouldn't think of wires as the culprit. Is it RPM dependent at all?

-Chris


Message: 1
Date: Fri, 20 Jan 2012 15:03:17 -0500
From: 200q 20v <a200q20v at gmail.com>
To: 200q20v at audifans.com
Subject: Re: misfire under light load
Message-ID: <1327089797.28533.11.camel at ybk.oraclecorp.com>
Content-Type: text/plain; charset="UTF-8"

Got some more information on the subject. Driving with radio on clearly
heard electrical discharge noise matching misfire.

Wires are over 6 or more years old, made by BREMI. Called several
supplies none have BREMI available, many offer BOSCH BS09268 but this
set will fit only 7A since wires are too short for 3B.

Has anyone purchased a wire set recently?

Regards,
Eugene.

On Sat, 2011-11-12 at 23:58 -0500, 200q 20v wrote:
> I would say here is a partial problem under full throttle and hight rpm
> and an impression of 3 or 4 cylinders misfire under WOT and 2000 rpm.
> 
> 
> -----Original Message-----
> From: Bernie Benz
> Subject: Re: misfire under light load
> Date: Sat, 12 Nov 2011 16:34:02 -0800
> 
> If no obvious leakage tracks on cap or rotor I would not expect a  
> problem there. And no problem under heavy throttle. I?d start by  
> looking at injectors, maybe one is sluggish to open.
> 
> Bernie
> 
> On Nov 12, 2011, at 3:01 PM, 200q 20v wrote:
> 
> > Fellow experts,
> >
> > Driving in 4th gear, 2000 rpm, increasing throttle feels like a
> > misfire in several cylinders. E.g. virtually no power.
> > It is not very pronounced when engine is cold.
> > It appeared to start after last track event. Leaving the track I
> > noticed slightly rough idle and above mentioned misfire while driving
> > home.
> > Changed several years old spark plugs (found the cheapest F5DPOR on  
> > Amazon).
> > Virtually no changes. There are no vacuum leaks (cold engine pulls
> > full boost with no problems) no codes in ECU.
> > Strangely enough during recent heavy rain misfires were much less  
> > pronounced.
> >
> > If left on idle a few misfires a minute can be heard.
> >
> > Wires and distributor cap are about 5 years old, much less then
> > average miles per year.
> >
> > I wonder if anyone has any ideas. I plan to look at replacing cap /  
> > rotor next.
> >
> > Eugene.
> > _______________________________________________
> > 200q20v mailing list    http://www.audifans.com/mailman/listinfo/200q20v
> 
> 
> 
> _______________________________________________
> 200q20v mailing list    http://www.audifans.com/mailman/listinfo/200q20v




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