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[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
> >