[16v] Newbie (of sorts), with questions.

[sciroccos at earthlink.net (Jim Ruffi)]

I suspect the Lamba system.  The mixture is constantly corrected as a result
of a signal from the oxygen sensor, as interpreted by the computer, etc.,
etc.  In situations where the O2 sensor or any of the connections or
components are messed up, you're gonna loose a lot of power and have
stumbling.

Before you start changing parts, keep in mind the fact that it could be
something small.  I was checking a whole bunch of stuff on my 8V a month
ago, and found the frequency valve response to be erratic.  Wiggled the
connector and found it affected the valve's response.  Turned out that the
terminal had pulled most of the way out of the plastic connector and was
barely making contact.

The main reason for my focus on this area is that it is partially bypassed
when the engine is cold/first started.

The Bentley will guide you.....
Now, if it would only guide me to fixing the last problem with my 85.....

Jim

>-----Original Message-----
>From: scirocco-l-bounces+sciroccos=earthlink.net@scirocco.org
>[mailto:scirocco-l-bounces+sciroccos=earthlink.net@scirocco.org]On
>Behalf Of Nate Mellom
>Sent: Wednesday, November 02, 2005 11:25 PM
>To: Scirocco list
>Subject: [16v] Newbie (of sorts), with questions.
>
>
>I've joined the hallowed ranks of the 16v'rs, with this:
><http://bronson75.tripod.com/redroc/>
>All's well and good, for the most part.  It has a somewhat floppy
>shifter, a messed up passenger seat, and $3145 is repair and parts
>receipts since August 2003.  My major concern is the fact that at low
>revs, pulling away from a stop, it has NO power, it chugs along until
>the revs get up (sometimes almost to the point of dying).  I played with
>it for a bit after work today, and came up with the following.
>
>:All of the following was done under the hood, fingering the throttle:
>
>When it's cold, it revs fine from idle.  Ramps up nice, comes back down
>to idle okay.  But when there's a point, during the warm up, when the
>idle drops a wee bit, and then it gets wierd.  If I lay on the throttle,
>the engine bogs down, and almost stalls, but as the revs get up, it
>evens out.  If I blip the throttle repeatedly, working the revs up, I
>can hear the airbox sucking, and sometime at lower revs (depending on
>how fast I blip the throttle), I get small backfires, seemingly inside
>the airbox.  As the blips continue, the revs go up, and if it drops to
>idle, it'll rev just fine, until I let it idle for 30-45 seconds, then
>the blipping/revving results in bogging and backfire popping.  I checked
>the air filter (as it seems like the airflow is being blocked), but it's
>  fine.  I haven't taken the cold air intake ducting off yet, but I
>don't think it's the problem.  From the reciepts, it seems the PO had a
>lot of cold-start issues (I don't), and he had a lot of work done,
>including new air/fuel filters, timing check, mixture check, tuneup (all
>these within the last year), and a new (used) distributor installed in
>August this year.  He had the throttle plate cleaned and adjusted as
>well.  I haven't had a lot of time to play with it, but I checked the
>basics this afternoon, vacuum hoses, air filter, a basic once-over.
>
>If anyone out there could give me some ideas, I'd appreciate it.  I
>don't have a manual for it (still trying to download the Bentley), and
>I'd like to get it running well.  My first MkII experience ended poorly,
>and I'd like this one to work out!
>
>Nate
>'81
>'88
>