Well, the car is still on
jack stands as I wait for a new Throttle Position
Sensor (TPS). The check engine light gives a trouble
code that indicates it is bad. Rick Patton (TPS
Supplier) is out in Arizona hob-knobbing with the
rich people at the Barrett Jackson Auction and won't
be back until Friday. Only Rick could have snow
follow him from Maine to Phoenix! In the meantime
I'm just content to go out in my 20 degree garage
and listen to it start right up with no fuss and
settle into a smooth idle.
The new TPS arrived at
noon so I installed it and got the same engine light
and trouble code. What the heck? Rick told me that
he has never had a TPS returned to his NAPA store as
being bad out of the box and now I've got two!
There's has to be something else going on here. I
double check everything once again and I've followed
the directions to the letter. At idle the reading at
the ECM should be 0.5V and at full throttle 4.3V.
The initial test is done with the key in the run
position with the engine off. I'm getting a
big ZERO. So I decide to wedge a small block in the
linkage to force it a little open and re-test
it..............0.85V. It works. Then I remember
Rick mentioning that you fine tune the idle voltage
reading by rotating the TPS driver nut. So I remove
the TPS from the bracket and turn the driver nut
clockwise about 1/8". Now when I engage the TPS to
the driver nut I have to rotate the TPS slightly to
fit it in the bracket. Success! A little fiddling
and I set it at 0.54V which is the optimum setting.
John Wilson subsequently told me that the TPS HAS to
be pre-loaded when fitted to the bracket which is
what I was doing by rotating it to fit in the
Now I do the full
throttle check and only get 2.55V. I get a mirror
and look in the carb and see only about 45 degrees
of throttle plate opening instead of 80-90 degrees.
Now what? Do I have to adjust the throttle linkage?
You shouldn't have to touch your throttle linkage
unless it was wrong to begin with. It's time to quit
for the day anyway.
OK......time to adjust
the long control arm linkage. Well that didn't help
any so I put it back to its original length and
decide to adjust the short control
arm..........damn....the throttle plate still isn't
opening any farther. As I'm leaning in and pushing
the linkage open I hear .........dink. So I work it
again and .......dink.....a definite metal on
metal......dink. A few more dink dinks and I spot
the source. The head of the high speed idle screw is
hitting the TPS bracket. The nut side makes it past
the bracket but the head doesn't! There's a
picture of it here.
A few turns of the screw and it clears the bracket
and I've got full throttle opening and a good
reading on my meter.
Time to re-check
everything: timing, idle, fuel pressure, look for
any gas leaks, put on air cleaners, get car off of
jack stands, tighten all lug nuts, toss fire
extinguisher behind driver seat..................now
time for a drive!
I'm back from my first
drive (just under 100 miles) in a TBI enhanced TR6
and I can't hear anything! Ya see, while working on
it, I pulled the passenger seat and carpet out and
the rear interior panel isn't in yet and neither is
the interior trunk panel. So I'm a big open
reverberating box all the way through to the trunk.
I can hear the fuel pump, the return gas getting
peed back in to the tank, the muffler, lots of road
noise, stuff in the trunk...etc...etc. It's LOUD.
But the car runs great. Fires right up even though
it's been sitting in a very very cold garage. Smooth
application of power. Pulls strongly with no
hesitation or stumbling. Great throttle response. I
can't be more pleased unless I find I'm getting 25
MPG. But that will have to wait for warmer weather.
The forecast is for snow tonight and over the
weekend. I'd like to get about 200 miles on it
before taking it off the road for all the other
stuff I want to do this winter. That way I can pull
the data and send it John for analysis. Then, if
needed, he emails a new program for the chip which I
can flash and update the ECM. This is very cool!
On my drive I stopped
back at the garage that did my fuel tank work
because he wanted to see the whole package. This
guy's an old time mechanic and he was blown away by
the whole installation and the quality of the
components. He really liked Rick's adapters and
John's regulator which are both custom milled from
January 31, 2007
time to do some "data logging". Basically, I've
downloaded a program (WinALDL) to my laptop that
captures all kinds of data from the ECM as I'm driving
along. John provides the interface cable with one end
connecting to the ECM and the other your laptop. I read
John's directions again which say "If you are
gathering diagnostic data for me, the only one I need to
see is the sensor data button."
ECM on floor at left & hooked to laptop
Program collects 23 different data points as you
So off I go
on a 40 minute drive that's about 30% around town and
70% on the highway. The laptop is collecting all the
data and the car is running great. I get home, check the
instructions, click "SAVE" and head back inside. Just
like the directions say, there's a small log file now
stored on my laptop with all the data. Before I send it
off to him, I'm reading a little further on and it says
towards the end: "The only other useful info that I
need to see when diagnosing your system is the BLM
tables." Arggghhh Engineers!! So what he really
needs to say is that there are TWO pieces of data that
he needs. Too late now to head out again.
January 31, 2007
Back in the car, another 40
minute drive, save both pieces of data and email it off
to him. I looked at the data in Excel and it seemed
strange to me that it didn't change much over the drive,
but what do I know?
I get an email back from John
saying something is wrong, the data doesn't change like
it should. After a couple of email exchanges he asks if
the WinALDL software settings show the ECM model# as
16144288? I tell him no, because his directions say:
"If you are using WINALDL for one of my kits, 99% of the
time you'll want to select model# 1227747." Lucky
me....I'm in the 1% with a different model# for my ECM.
Back in the car for another
drive and data logging. This data proved good and he's
sent me a new chip file to flash. After the data logging
experience, I hope his flashing directions are accurate!
I've emailed him to confirm and as soon as I hear back
I'll be flashing the update to the chip.
So at this point I have about
150 miles on the car that's about 30% around town and
70% highway. I've gone through, at best, 1/2 a tank of
gas, which means I'm getting at least 25 mpg compared to
the 15 mpg that I used to get. The car seems quicker
with no flat spots around 3000 RPM. Basically, it just
keeps pulling through the gears. Drivability is great
but I do have to re-learn how to start and drive it.
KEEP THE FOOT OFF the gas pedal when turning the key to
start the car. And......there's no need to blip the
throttle anymore before taking off from a dead
stop.....except it sounds way cool to do so.
No drive today, it's in the
single digits so I think I'll stay inside. John emailed
me a new program to flash to the ECM chip. Basically, my
data log showed him that the car was a little on the
rich side at idle and lean on the high end at 3000 RPM
and up. He adjusted the VE tables to get the calibration
smoother. The O2 sensor was correcting the mixture but
it runs smoother when the O2 sensor doesn't correct
anything. Now this is way cool....no need to fiddle with
mixture settings on the carbs.....no more hoping you've
adjusted them the same....no more....messing it up with
your own incompetence.!
So I pulled the chip from the
ECM and flashed the chip to the new profile. The
directions and pictures are at the "Flashing a Chip"
link. Maybe I'll take it for a ride tomorrow and see if
I notice any difference.