Communicative Cars

[Scott Fisher <sefisher@cisco.com>]

So a few days after I picked up my '83 Coupe, I wrote to the list to ask
about the rev-limiter.  Four or five people wrote to me privately to
instruct me about the difference between the 4cyl and 5cyl relays.  As I
left for lunch that day, I wondered where the relay panel was in this
car.

On my way to lunch, I felt something bumping my shins and looked down to
see that a trim panel had fallen from under the dash.  In addition (and
exciting in traffic!), I felt that something was sliding around on the
floor, and had wedged under my right foot.  It was a relay...  Okay, so
I've got a car that not only listens to me, but communicates as well.

Some time later, I got good advice on how to identify *which* of the
many relays was actually the FPR, also from the list.  I experimentally
verified this by the simple expedient of pulling it and having the car
shut down. :-)  I also disassembled it and figured out how it worked,
thinking I could hot-rod the relay itself.  That wasn't successful, but
I did determine how it functioned (there's a magnetic coil that pulls a
switch to one of two different positions, and I was able to determine
which one is run-mode and which is stop-mode).

Finally, a helpful q-lister had told me which of the two relay terminals
I should jumper to test whether it *was* in fact the FPR that was
causing my early rev-limiter woes (the BIG terminals, if you're worrying
about your own car).  So on Friday, I figured I'd just install the
little jumper I'd already made between the two big terminals and try it
out over the weekend.

On the way home, I shifted into second gear at about 4800 RPM, caught
the rev limiter as usual, and let the clutch out -- to find no power at
all.  I rolled into a parking lot, trying to figure out where there was
a phone, whether to call AAA, etc.  I tried starting the car and it
turned over very easily, but... felt as though it was out of gas.

I popped the hood, pulled the cover off the fuel pump relay, and tried
holding the magnetized switch in the run-mode position.  I could hear
the fuel pump working!  I then turned on the ignition, let go of the
magnetized switch, and could NOT hear the fuel pump working.  Oh, this
is simple, I can fix this... now what can I use to wedge the FPR in its
proper location?  Paper wouldn't do it... thin cardboard wouldn't do
it... I need something thicker and non-conductive, what can I find in
the car right now to get me home?

I found a squeegee in the glovebox, whipped out my pocketknife, and cut
off a section of rubber.  I wedged that into the relay in such a way
that it would hold the switch in run-mode, heard the fuel pump whirring
as I installed the relay, and hopped back into the car to try starting
it.

It started immediately, running smoothly.

I drove home, and was pleased to note that the engine would rev as high
as I wanted it to (only about 5500-5600 RPM, but enough to prove that it
*had* been a 4cyl relay).

So over the weekend, I fabricated a quick fix and installed a simple
toggle switch (after a couple of days spent jumping out of the car to
pull one end of my jumper out of the relay panel, having a switch in the
car is not only incredibly simple, it sends me back to the days when I
had the switch box on the floor of the E Production race car; maybe I
oughta switch the low-voltage lead to the coil, just to keep the
illusion that much more authentic :-).  I also installed a manual
override on the engine fan at the same time; it had been stuck in the on
position.  The switch panel I found had four lighted toggles, so I now
have two unused switches... yeah, one for the coil, and one for the
driving lights, that's the ticket! :-)

The final report is that the car is VERY neat with full power.  Best of
all, now that I can play with the whole powerband, it's neat the way
each shift puts you into the fat part of the torque curve in the next
gear.  I could get used to that.

Still haven't put in my MetalMasters yet, though -- later this month, no
doubth.  And then it'll be time to look for rear shocks.  But for now,
it's fun to have a car that tells me what it needs, and as always it's
fun to have a car that's getting better, little by little, under my
care.

--Scott Fisher