[s-cars] Mystery Miss

[Bob Rossato]

Presuming that Mr. Myers and I have the same problem, and that is a big presumption, if it is a POS issue why would mine only manifest itself after several days of sitting.  Stone cold after one day should be the same as stone cold after 4 days.  This seems to lend some plausibility to a fuel pressure issue maybe?

Bob R.

-------------- Original message from Robert Myers : -------------- 

> 
> Hmmmm... Swapping the PSO leads did move the miss. I let the engine run 
> just barely long enough to pull the injector connectors and then shut it 
> off immediately while the miss was still present (before giving the engine 
> enough time to warm up). I restored the PSO wires to their original 
> positions. Fired it up again and the miss was gone. 
> 
> I wonder if one of the crimp 
> connections I did last week might be just a bit loose and not making 
> perfect contact and by handling the harness I may have reestablished 
> contact (for now). No, that shouldn't be the problem because the miss 
> would then have remained in the same place regardless of the PSO connection 
> positions. Perhaps this is a strange PSO failure but, if it is, it is not 
> a failure mode I've seen before. Usually, IME, when a PSO goes it is 
> binary. It either works or it doesn't. 
> 
> Does anybody have a spare known good PSO they can loan for a brief test? 
> 
> At 09:42 PM 9/29/2004 -0400, Bruce Mendel wrote: 
> 
> >don't rule out the POS until you swap both connectors while it's cold and 
> >stumbling to see if the problem moves to a different cylinder...they have 
> >strange behavior, and change their behavior based on heat. 
> >----- Original Message ----- 
> >From: "Robert Myers" 
> >To: 
> >Sent: Wednesday, September 29, 2004 9:34 PM 
> >Subject: [s-cars] Mystery Miss 
> > 
> > 
> > > 
> > > Hi Y'all, 
> > > 
> > > Thanks to all who responded about my son's dealings with his Mercyless 
> >Benz 
> > > stealer. Apparently contacting the corporate offices helped. He finally 
> > > has his car back from the stealer. Now on to the topic of this post. 
> > > 
> > > My '95 urS6 (RS2ed) has developed a mystery miss. 
> > > 
> > > It happens only when the engine is stone cold. It disappears after the 
> > > engine has run for less than two minutes and does not come back until the 
> > > next time the engine is stone cold. 
> > > 
> > > FWIW, I have localized the miss to cylinder #4. 
> > > 
> > > I have pretty much ruled out a fault with the PSO since the miss 
> >disappears 
> > > after the engine has warmed up a bit. 
> > > 
> > > I don't think it is a problem with a weak coil because there is absolutely 
> > > no miss at high boost which is when a weak coil would show up. 
> > > 
> > > I put new plugs in about a week ago so that shouldn't be the 
> > > problem. Performance is superb after the engine warms up. 
> > > 
> > > Plug boots are reasonably fresh. 
> > > 
> > > The wires to/from the coils have been freshly reinsulated with shrink 
> > > wrap. I am pretty confident that I did this job correctly. 
> > > 
> > > What in the name of the Audi gods remains? Any ideas? 
> > > 
> > > 
> > > Bob 
> > > Random Bushism: "A tax cut is really one of the anecdotes to coming out of 
> > > an economic illness." George W. Bush, on The Edge With Paula Zahn, Sept. 
> > > 18, 2000 
> > > _____ 
> > > Robert Myers 304-574-2372 
> > > Fayetteville, WV 
> > > '95 urS6 Cashmere Grey 
> > > _____ 
> > > 
> > 
> > 
> >---------------------------------------------------------------------------- 
> >---- 
> > 
> > 
> > > _______________________________________________ 
> > > S-CAR-List mailing list 
> > > S-CAR-List at audifans.com 
> > > http://www.audifans.com/mailman/listinfo/s-car-list 
> > > 
> 
> Bob 
> Random Bushism: "If the East Timorians decide to revolt, I'm sure I'll have 
> a statement." George W Bush, Quoted by Maureen Dowd in the New York Times, 
> June 16, 1999 
> _____ 
> Robert Myers 304-574-2372 
> Fayetteville, WV 
> urS6 - Cashmere Grey 
> _____ 
>