Having played with a number of issues with my 940, and in most cases wanted more 'scientific' data I have been thinking about adding guages etc inside..the problem being i would end up with many guages which would look ugly and not be very usefull. My present problem being OD related and imm thinking of a tell-tale light in the car to let me know when the solanoid isnt getting power...which got me thinking about something i was thinking about before...

Why not have a single lcd display that could monitor many things and show warnings if things went out of tolarance..it could also have the ability to data log information onto...say..a floppy disk for analysis off the car..

now i have an advantage here..cos computers are my thing...and this stuff iusnt that hard (or expensive - compaired to multiple guages)to do..what i have in mind is a simple computer module that scans a number of sensors and monitors the outputs to a lcd display/audible alarm system...

The thought is a dos pc based system that is powered from the car, boots on ignition from a floppy disk and saves dat to a second floppy either becasue its told to, or on a sensor going out of totlarance..

now my question to you guys is two fold..1 - what should one monitor and 2 - does anyone else think it would be a good idea?

so far my monitoring ideas are:-

inlet presure/temp
intercooler entry presure/temp
intercooler exit presure/temp
Manafold Presure/temp
Oil cooler temp
oil presure
water temp (cylindrr head)
water temp/presure (top hose)
water temp bottom hose
cylinder head temp
turbo temp (sensor may be fun!)
exhaust temp (into cat)
exhaust temp (out of cat)
rpm
speed (if i can work out a good way of going it!)
gear?
OD selected
OD solanopid power status
voltage at battery
voltage at alternator
Brake status (lamps on or off)
ambiant temp
ambient humidity
water temp in expansion tank
water level in expansion tank
date and time!

assuming these can genrally be sensibly stored i recon i can store something like 4000 readings on a floppy for off car analysis...

not saying im going to do it...but i know how to, question is is it worth it? - i figure it will cost me maybee $500 to do...

You missed some important ones:

Road surface temp.
Tranny temp.
Diff temp.
Tire pressure sensors.
Beer cooler temp.
Passenger BS detector.
GPS.
MPG calculator.
Oil conductivity.
Beer remaining sensor.
Tranny fluid level monitor.
Percent water in gas.
Charging current.
Oil filter pressure drop.
Fuel pressure.
Altitude.
Brake fluid level sensor.
Brake fluid water contamination monitor.
Barometric pressure.
Road surface coefficient of friction.
Wind velocity.
Wind direction.
Acceleration (+/-).
Tire slippage.
Tread wear monitor.


Turbo temperature's easy -- use a thermocouple. They're standard on gas turbines and jet engines.

--
Don Foster (near Cape Cod, MA)

Re: the overdrive problem
Mine sometimes fails to disengage as I come to a stop. I also had a jerkiness at certain rpm as if the trans was rapidly going back and forth between gears. (This went away with a plug change--fancy maint center hadn't gotten the plugs in tight!).

Trying to diagnose the problem, computer or trans, I rigged three Radio Shack LEDs (12v) to the pins sending 12v to the three trans solenoids. Put them on the ledge of the instrument cluster. Got a cute light show as it went through the changes. Computer was doing as it should. OD light was off as the car shuddered towards a stop.

I haven't tried it yet but I read here that the OD solenoid sticks and that the cure is changing it. I know that pulling mine, inspecting and cleaning it, then flushing the fluid, did no good.

When I resolder a relay, I never stop there. I disassemble the mechanical contacts (remove the spring and pry the movable contacts off the windings). I then grind/file/burnish the contacts because I almost ALWAYS find pits, build-ups and discoloration from arcing. My car is 8 years old and I haven't bought a new relay yet. Maybe I just have too much time on my hands but I figure if you're going to break out the soldering iron, might as well go the whole route.
--
Bob Kraushaar '94 945T, '91 940T, '88 240, '94 F-150, '68 Shelby GT-500 KR

I like it. You could switch between monitor screens (coolant system, fuel delivery, etc.) and even add graphics to highlight the sensor positions (assuming an on-board display). But what would be truly cool would be to port the readouts to a heads-up display on the windshield!
--
Bob Kraushaar '94 945T, '91 940T, '88 240, '94 F-150, '68 Shelby GT-500 KR

I was thinking of having the display auto scan, with a bias to the readings closest to the preset tolarance limits, probably with some method of manually causing a jump to next/last guage. The thought was probably to mount the LCD (back lit) in the cubby hole under the radio on some sort of slide out and hinge up arangement...

HUD's are a bit beyond where i was going!

Great idea, But the biggest and most expensive part by far will be sourcing and fitting all the sensors.
Some are already in place but if you monitor these make sure your measuring device has a high impedance (>1 Megohm) input or you will upset/damage the car electronics. Why not use an old laptop as the basis, you could then boot from and save to the hard disk.
Colin

Well you are not far from where i started... I wouldnt use a HD as they Are FAR to sensitive to shock damage when running ..but we dont need a lot of pc power here and i have a old 8086 laptop that only has floppy drives and runs from 12 volts...of course i would need to produce a custom package to handle and switch the inputs...and of course you are right some of the sensors would be expensive..but you would be amazed what u can buy as ssd's these days for under £5

...oh and before u scream people do use hd's for this...i know and they are always spring mounted etc and i just dont fancy it...

Interesting idea for diagnostics. It does sound like you would have to install some sensors to do it. I have an ignorant question though, for existing sensors if you splice in and do a take-off will you create a diminished signal that the ECM will have trouble understanding? How would you do the wiring? I would also be interested in doing something like this for my 960. I was thinking I could place the display paned in an empty spot below my radio. I would love to hear some details on how you would do this.

92-960, 190 000km

exactly where i was thinking of for the display!

I have a simple rule...KISS - Keep It Simple Stupid..

if i do do it it will put all new sensors in aon there own wirring (hopefully with a didgital interface - poss fibre optic *doubtfull due to cost*)

the electronics isnt difficult, or the programming its the cost of the sensors etc that worrys me - and the difficulty of installing the display etc to look good AND be reliable!

Hi mate,


I think that's a cool idea but some of the sensors you are intending to monitor are already being 'monitored' by the ECU for e.g cruise control status, rpm sensors, throttle position, engine coolant temp. bulb failure, gear position sensors and some other things. I think monitoring fuel pressure is a good idea because you will then be able to determine if your main pump is going to die on you in middle of nowhere. Coolant level.. I think there is a D.I.Y in the FAQ on how to do it. Ambient temp sensors are already been fitted in cars with ECC.

The setbacks, I think, in cars is that there is no way of telling if the sensors are going south until they have actually gone south. Now if you can come-up with a 'computer' that can test these sensors, the fuel injection system, fuel pumps, starter, alternator, wiring circuits, the ECU and displays the results in the LCD mounted at the dash even before I leave my driveway everyday, I am willing to take a ride with you and buy your idea. I may even develop an aftermarket over here to sell your products to other car owners.

Keep working on the idea. Every accomplishment starts with a simple question. Thats is "Why not ......."?

regards,

velan

Kuala Lumpur, Malaysia.

these system already exist! whats putting me off buying one is the COST!

the idea of self diagnostics on the sensors is interesting - posisbly not practicle...

not sure if i will do it yet...just playing with the idea, but considering things if i could make it work..i might just consider marketing it!