[16v] low end torque (or the lack thereof)

[indiana_red@hotmail.com (Ken Bates)]

HEY.  Maybe Im not crazy.....
I have almost the exact same symptoms.  Mine is not ready to drive so I
can't confirm the low end torque part but the throttle response is as you
say.  If I quickly open it to about 1/4 open then it takes a few seconds to
"spool up"  sometimes stumbling early along the way.  Idles very smooth
though and when its spinning 2-3k/ no load,  it sounds even and smooth.  I
am using the test harness set-up as described on Shannons site and am
getting about 10ma.  At Idle it fluctuates only .1 ma up and down about
every second.  i thought the 02 sensor was supposed to make this fluctuate a
full ma or so.  Also tripping the WOT switch at idle bumps the reading
down(richens) .1 ma.  Not sure if this is normal. As an enrichment function,
I expected a bigger effect.
This motor has not been "cracked" open since I drove its original host 800
miles last summer so I am reluctant to suspect cam timing.  Although I did
replace the Tbelt between then and now.  I'll have to take another good lok
there.  Dist timing looks right on.
Hoping to glean a little help for myself rom this thread
per comment below, .7V from the 02 sensor?  Where do I test this exactly?

Ken
'79 Scirocco 16v project "McFly"
"...it's working...It's Working...!!"
'86 16v (organ donor)
VORTEX:  "Indiana Red"


----- Original Message -----
From: "T. Reed" <treed2@u.washington.edu>
To: "Jason" <jason@scirocco.org>
Cc: <scirocco-l@scirocco.org>
Sent: Tuesday, August 13, 2002 1:32 PM
Subject: Re: [16v] low end torque (or the lack thereof)


> > Toby, I haven't been paying close attention to the list lately, so I
> > apologize in advance if I ask questions you have already answered.
> >
> > First, being that your post is a few days old, have you made any
progress?
>
> Not really. I have noticed that setting my dpr current to 5 mA instead of
> 10 mA increased power around 4-5k a little bit but took more away from the
> low end. I think it's unlikely that this is a fuel problem, though. My
> exhaust barely even smells :) and I rarely get smoke from the tailpipe
> except during startup and even then it is minimal. My oxygen sensor
> voltage is reading around stoich (.7 volts, no?). But.. I've been wrong
> before.
>
> > Seconly, is the problem only present when you have the A/C on, or does
the
> > A/C just make things slightly worse?  When you say that the car is "slow
> > off the line" without the A/C on, how slow?  The 1.8 is very sluggish
under
> > 2000rpm -- but it shouldn't be more than about 0.5s to rev it to 2k in
neutral.
>
> It takes just under 2 seconds to rev it to 2k from idle in neutral. Most
> of that is just waiting for the engine to respond to the change in
> throttle position. It hesistates at idle and then begins responding after
> a second or so. Really annoying..
>
> > My R134a A/C kills the power of my 2.0 -- not the way you describe, but
it
> > feels positively dead.
>
> The power loss is definitely noticible above idle as well, but less so.
> It's not bad at all when I'm just going at a cruising speed.
>
> > Your car sounds like a timing issue.  The fact that 6' ignition advance
> > (i.e. stock advance) makes things worse points even more towards that.
Are
> > you absolutely sure your cams are timed right?  If so, try running a
little
> > cam advance -- 4-6'.  That should help bring the torque curve down.
> >
> > Jason
>
> I will pull off the timing belt cover and double check my cam timing
> -again- today. I've already had my timing belt slip a couple teeth before,
> so anything is possible but I'm pretty sure it'll still be dead on.
>
> What I was saying in my other post today was that maybe my timing advance
> is not functioning at all. And that's why I need to advance it all the
> way to get decent performance.
>
> Hmm.. more stuff to look in to.
>
> -Toby
>
> >
> > >I have to turn the A/C off at every stop. If I don't, 0-10 mph takes 6
or
> > >7 seconds (not an exaggeration -- the people behind me start riding my
ass
> > >when the light has been green for that long and I'm barely rolling).
The
> > >only alternative is to rev to 2 grand (still about 1.5 seconds) and
drop
> > >clutch, which sometimes chirps the tires (lightly releasing the clutch
> > >just makes the rpms dip back down to idle and then rise slowly.)
> > >
> > >The car runs great/fine above 1500 rpm..
> > >
> > >Is this normal? It can't be.. for the longest time I've been assuming
the
> > >16v engine just blows off-idle but now I'm think I have serious
> > >engine issues (but is it fuel or ignition? or mechanical?).
> > >
> > >Where should I start looking?
> > >
> > >Ignition timing is set to full advance (setting it at 6 degs just makes
it
> > >worse)
> > >DPR current is set to 10 mA fluctuating +/- 1 mA
> > >Idle stabilizer is working
> > >Plugs, plug wires, bosch cap, rotor, hall sender all new
> > >O2 sensor within last year and a half
> > >Fuel filter changed
> > >Euro intake cam
> > >Crank<->Cam and Cam<->Cam timing dead on at last check
> > >Idle air bypass screw set mostly by experimentation because no
adjustment
> > >   could yield a proper dwell meter reading
> > >Idle and full throttle switches test out okay
> > >3" sewer pipe running to stock opening in lower airbox
> > >k&n air filter, possibly with some crankcase breather oil soakage on it
> > >All vacuum hoses replaced
> > >Intake boot leak next to throttle body patched
> > >No exhaust leaks - new downpipe and new dynomax superturbo muffler
> > >
> > >
> > >Any ideas? Even without the A/C the car is slow off the line..
> > >
> > >I would appreciate any input!
> > >
> > >Thanks,
> > >
> > >-Toby
> > >
>
>
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