[urq] More of the car that wouldn't start
Thatcher Hubbard
thatcher.hubbard at gmail.com
Fri Nov 5 12:51:52 EST 2004
You know, I hadn't even thought of that, despite the fact that I had
examined that hose while I had it out of the car and noticed that a
couple of the wire hoops had busted out of their fabric covering. The
info I'd seen on that hose failing was all "I was driving on the
highway and suddenly", but I guess if it's a small tear it would be
just like taking the oil cap off.
As a troubleshooting technique, can I just wrap the thing in duct
tape? I know that it would not last, especially not at any kind of
RPM, but just to see if I can get the car to idle.
I am also going to check the duty cycle. The car has not had much
work done to it over the years, but what has been done was not
necessarily by a great mechanic. When I removed the head from the car
and was (carefully) removing the EM bolts and studs, I found a couple
of points where someone had started to drill the studs out and then
thought the better of it. The engine shop didn't think they'd be a
problem, but it was something of an indicator for me of how well it
had been maintained.
On Thu, 4 Nov 2004 17:28:46 -0800, Buchholz, Steven
<steven.buchholz at kla-tencor.com> wrote:
> ... one of the things you shouldn't worry at all about is the ignition
> timing ... this is set very precisely based on the flywheel teeth and
> the reference pin ... I suppose damaged flywheel might screw timing up,
> but that would most likely affect high rev operation (IMO). Any
> adjustment of the distributor does not actually change the ignition
> timing ...
>
> I agree that it is likely that there is unmetered air getting into the
> intake tract ... and IMO one of the prime suspects is the same intake
> hose we've been talking about on another thread. The hose from the top
> of the airflow sensor (igloo) to the turbo inlet is notorious for
> leaking, and sometimes the breaks in the hose are not easily visible.
> The hose is rather simple to remove and test to see if it is leaking.
> Removing the vacuum line at the top of the igloo will cause the
> possibility of unmetered air, but I doubt it would be enough to screw up
> the idle. You may want to plug it just to be sure ...
>
> One other thing to beware of is the OXS Freq Valve ... do you hear it
> buzzing at all while the engine is running? Do you hear the buzzing
> start and stop while the engine is running? If you have a duty cycle
> meter, hook it up to the diagnostic plug in the loom near the firewall
> on the passenger side and see what you are reading for duty cycle. If
> you close the WOT switch at idle the ECU will force the duty cycle to
> 50%, which tends to speed the idle up a tad on my car ...
>
> Given you are just talking about idle the manifold pressure line to the
> ECU is not likely to be contributing to your problem (IMO), but as
> always ... you can never say for sure for something that is not
> configured properly ...
>
> Bon chance!
> Steve B
> San Jose, CA (USA)
>
>
> >
> > It will start now, as it would yesterday. I checked the timing (that
> > is, the position of the cam versus the crank) and I was indeed off a
> > tooth, although when I restarted the car it ran even more roughly than
> > before.
> >
> > We've tried adjusting the distributor, the range in which it will
> > actually fire the coil is small, and it doesn't seem to matter where
> > we position it, the car will die if I don't use the throttle to keep
> > it at about 1k rpm.
> >
> > I also checked all of my vacuum routing and such (thanks for the ETKA
> > slides and the routing diagram Louis-Alain). There were two things
> > that I had not connected, the first being the small hose that goes to
> > the outside/underside of the igloo towards the front, and the ECU.
> >
> > The ECU hose deserves its own discussion. The digrams I have clearly
> > indicate that it go on the left-rear port (from the front of the car
> > looking back) of that group of four small ports that come off the back
> > of the IM. The left rear port is slightly larger than the other three
> > though, which would indicate to me that a larger hose needs to be
> > attached to it. My ECU hose is so brittle that I had to cut it back
> > and put one fo those inline hose splices in it. I was wondering if
> > anyone else had noticed this.
> >
> > So, the car will start after a crank or two (right away pretty much)
> > but will not idle at all, will run pretty roughly at 1k rpm and though
> > the engine will rev when I give it more gas, it's still pretty rough
> > (not like it used to be). It seems like a timing issue, but I'm
> > running out of places to be wrong on that. I'm pretty sure the coil
> > wouldn't even fire if I had the distributor in wrong (wrong relation
> > to cam) and like I said above, it doesn't seem to matter where we
> > position the distributor body versus the dizzy itself, the car still
> > doesn't run well.
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