simon
considering you talk allot about it but not have done it your self as you prefer the gauge not moving ...this is called denial you don't want the gauge to move because it suits you (somethings are best not knowing ) don't worry mate I have been there

I don't disagree every one has there opinion..... but just imagine next time your laying in a hospital bed and all the monitors used maybe just as good as the ones on the dash as a landrover . one gauge only that does not move .....they also wont be able to check blood pressure LOL (oil pressure ) but they be able to tell you out side temp if that's any help

gauges can be installed any where its a personal choice many don't like cluster ..like I don't like those who run 7 inch GPs screen on the windscreen blocking a view with a dash cam in there face creating blind spots forget to mention there I phones also

you will only become to realise humans also need to be monitored ..same goes with an engine regardless of its health ...if you want to rely on the coolant gauge and oil light good call mate

ps giving my line of work it becomes natural .... I like to know how my engine performs in all conditions and its health means fixing the issie sooner
many office jockeys like there car clean just like there desk just saying
 
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Simon098 said:
Yes because you aren't modifying the signal for control purposes.
Your tapping off the line to read the voltage and then send it to the gauge in the instrument cluster.
Click to expand...
If you tap into that signal IMO it will be garbled, i doubt you can invent any signal converter without resistance so the ECM will be mixed up cos the ECT sensor works with voltage sent by the ECU then the ECU calculates the temperature based on the difference of the return voltage which with your setup will be divided... there will be 2 inaccurate readings: one to ECU and one to the gauge, also the ECU acts already as a PWM converter, that behaviour of the gauge in sections is not managed by the ECU but the gauge is conceived to work so....i see you know electronics so better read more about the engine management then you'll be perfect ;)
 
sierrafery said:
If you tap into that signal IMO it will be garbled, i doubt you can invent any signal converter without resistance so the ECM will be mixed up cos the ECT sensor works with voltage sent by the ECU then the ECU calculates the temperature based on the difference of the return voltage which with your setup will be divided... there will be 2 inaccurate readings: one to ECU and one to the gauge, also the ECU acts already as a PWM converter, that behaviour of the gauge in sections is not managed by the ECU but the gauge is conceived to work so....i see you know electronics so better read more about the engine management then you'll be perfect ;)
Click to expand...

ozzy, the reason I haven't done it isn't because I don't want to do it, I haven't gotten round to it yet. I managed to adjust my speedo to work fine with the difference in tyre size and it reads just as accurately as any normal speedometer now.

I estimate that the resistance they use in-line is likely to be about 3k with the ECT sensor (given the resistance table shown, with any other value, you would not get a voltage swing great enough to give a good resolution). So you think a high impedance input to a microcontroller in the realms of 1Mohm is going to make a difference to the reading? Yes, it will, but not nearly enough for me or even yourself to care about, your talking millivolts at most. Even if it uses a constant current to generate a voltage, your still using a high impedance input.

aN1x3PU.png


Obviously, functional testing will prove whether it works or not, but I'm going to try it anyway.
 
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ozzyboydeano said:
ps giving my line of work it becomes natural .... I like to know how my engine performs in all conditions and its health means fixing the issie sooner
many office jockeys like there car clean just like there desk just saying
Click to expand...

I'm assuming from this, you think I work behind a desk? :p

I'm not disagreeing with you, I'm saying there are other ways. But you seem to think that me and everyone else is a complete idiot, so I'll leave this thread now.
 
Simon098 said:
I'm assuming from this, you think I work behind a desk? :p

I'm not disagreeing with you, I'm saying there are other ways. But you seem to think that me and everyone else is a complete idiot, so I'll leave this thread now.
Click to expand...

and there people think I don't have a sense of humour
 
Update on disco! fully serviced today inc all oils, decatted it, removed pump from tank cleaned all that as it was gummed up! my mate tested fuel pressure and it was just over 60! he said that was spot on, it has definately improved it and it pulls better with what i have done to it, lets see what its like with caravan on back!
 
Did you check the pressure before you did all the stuff above? Did you also change the fuel filter?

Oh, and how was it gummed up?

Cheers
 
Didnt check pressure before i started to do things no! the gauze on the bottom of pump had a load of black crud stuck to it cover most of the gauze so rinsed it with petrol then used an air line from a distance to blow out! it needed cleaning! And yes changed fuel filter, is there some kind of filter at the front or a mesh insert of some kind?
 
leeby7 said:
Didnt check pressure before i started to do things no! the gauze on the bottom of pump had a load of black crud stuck to it cover most of the gauze so rinsed it with petrol then used an air line from a distance to blow out! it needed cleaning! And yes changed fuel filter, is there some kind of filter at the front or a mesh insert of some kind?
Click to expand...

There is a mesh under the FPR.

http://www.discovery2.co.uk/Fpr.html

Cheers
 
leeby7 said:
Didnt check pressure before i started to do things no! the gauze on the bottom of pump had a load of black crud stuck to it cover most of the gauze so rinsed it with petrol then used an air line from a distance to blow out! it needed cleaning! And yes changed fuel filter, is there some kind of filter at the front or a mesh insert of some kind?
Click to expand...

I don't like the sound of that "load of black crud" all over the filter on the fuel pump. If it was a slimy, gooey mess like extra thick treacle then it could be a case of "Diesel Bug".
It's a fairly well known phenomina amongst marine diesel users where the atmosphere tends to be a quite damp; it's a biological growth which lives in the interface between any moisture at the bottom of the tank and the diesel fuel which sits on top of the water. There is a thought that the increase in temperature of the diesel in the tank caused by the warmer fuel returned to the tank from the Td5 engine might also have an effect by increasing the rate of the growth of the diesel bug.
Treatment is quite easy, there are additives which can go into the tank with the fuel which will destroy it. There is also a thought that keeping the tank full, or at least above half full might go some way towards reducing the bug.

http://www.ebay.co.uk/itm/MARINE-16-DIESEL-BUG-BIOCIDE-TREATMENT-100ml/152610002483?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
 
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Also when the pump's filter is black it can be sign of leaking injector copper washers which will cause serious missfire in the near future as it becomes worst
 
sierrafery said:
Also when the pump's filter is black it can be sign of leaking injector copper washers which will cause serious missfire in the near future as it becomes worst
Click to expand...

I never got a misfire. Just gutless and under heavy load in 3rd gear or higher, the engine would die due to getting air in the injector rail.

Wouldn't start, just turned over and over, then just as the battery was almost flat it would usually start up.

Changed the seals and now everything is perfect.
 
Simon098 said:
I managed to adjust my speedo to work fine with the difference in tyre size and it reads just as accurately as any normal speedometer now.
Click to expand...

Got any code you could share?

I started bastardising some code I found from elsewhere but stalled due to other commitments. My intention was to make it dual channel so that the VSS signal could be intercepted in 2 places, the feed to the clock, and the feed to the cruise control ECU.

Also agree on the impedance of most MCU ADC's not being an issue.

Probably simpler to just add a 2nd sensor and instrumentation though - load of code on my own setup for STM32 here -> https://github.com/BennehBoy
 
Yeah I'm not at home right now but I'll sort something out for you later. I used an ESP8266 as the clock speed is much higher which negates the issues of scan time vs output.
 
Simon098 said:
Changed the seals and now everything is perfect.
Click to expand...
That's why you didn't have missfires cos you changed them before getting there ;) the gist is that the black deposit on the pump's filter is sign of failing washers;)

as about that plan with the PWM converter for the ECT gauge even if the impedance is not a factor i still dont understand what's the gain of it as long as the ECU is already delivering PWM based on ECT input and afaik the gauge's internal circuit is managing the needle in those 3 sections not the ECU :confused: , the gauge will behave the same with your converted signal too if you dont modify something in the instrument's circuit but if you do and make it work linear you dont need other signal cos you can use the one delivered by the ECU
 
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sierrafery said:
That's why you didn't have missfires cos you changed them before getting there ;) the gist is that the black deposit on the pump's filter is sign of failing washers;)

as about that plan with the PWM converter for the ECT gauge even if the impedance is not a factor i still dont understand what's the gain of it as long as the ECU is already delivering PWM based on ECT input and afaik the gauge's internal circuit is managing the needle in those 3 sections not the ECU :confused: , the gauge will behave the same with your converted signal too if you dont modify something in the instrument's circuit but if you do and make it work linear you dont need other signal cos you can use the one delivered by the ECU
Click to expand...

I'll have to test it and find out. I know if you test the gauge with Nanocom, it definitely has resolution. As for if it's controlled by the instrument cluster, I don't know yet.
 
The test of the ECT gauge with nanocom will work only for the normal operating range(middle between 70 -119*), for this test the ECU sends the default value of 88*C which makes the gauge go to the middle, that's all you can do with nanocom, if you are so determined you can check(while the engine is heating up) with oscilloscope the PWM signal sent by the ECU which IMO is actually the converted sensor input and there's a filter in the instrument which sends the needle to one of those 3 sections according to the calculated temp range
 
sierrafery said:
The test of the ECT gauge with nanocom will work only for the normal operating range(middle between 70 -119*), for this test the ECU sends the default value of 88*C which makes the gauge go to the middle, that's all you can do with nanocom, if you are so determined you can check(while the engine is heating up) with oscilloscope the PWM signal sent by the ECU which IMO is actually the converted sensor input and there's a filter in the instrument which sends the needle to one of those 3 sections according to the calculated temp range
Click to expand...

I know with nanocom you can tell the ECT to pulse up. When you pulse it up, it moves up in tiny increments. And yes, I was going to measure the signal to see what frequency it uses first, as the gauge is likely to have an RC filter on it to convert it to a voltage which it can then use to give it the correct position on the gauge.
 
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