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Discussion Starter #1
I've been trying to find someone that can tweak the ECU to make the temperature read 10 degrees higher than it actually is in order to save gas. Nobody can do it. They can "chip" the engine but not the gas.

I got an idea. I am going to remove the coolant temp sensor behind the alternator and bake it in the oven at 500 degrees to see if it throws it off when I reinstall it. If the coolant temp sensor reads higher (and not lower) it should tell the ECU to stop injecting gas at a lower temperature.

I will report back what happens.
 

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I got an idea. I am going to remove the coolant temp sensor behind the alternator and bake it in the oven at 500 degrees to see if it throws it off when I reinstall it.
Brilliant idea ... beside the fact that making that has no logic it has plastic on it you know ?

 

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No I didn't know it had plastic on it. Not sure why they would manufacture it using plastic.

Maybe I can just hold a flame to the metal tip it and see if that works.

If it registers 10 degrees higher than before ... that should make the ECU stop injecting gas into the coolant. Since my temps went down it feels like my MPG has been effected.
 

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No I didn't know it had plastic on it. Not sure why they would manufacture it using plastic.
cos the connectors are plastic as they have to provide isolation between terminals
....

If it registers 10 degrees higher than before ... that should make the ECU stop injecting gas into the coolant. Since my temps went down it feels like my MPG has been effected.
I think you don't really undertand what's going on seing the bolded part o_O

I explaind in your other thread that if you trick the reading to be higher while the real temperature is lower it will be powerless... heating up a NTC sensor with a flame or what ever else will not make it read higher, eventually will ruin it
 

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why is your engine injecting gas to the coolant? that sounds like a head gasket
 

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It reads temperature based off of impedance, while you could add resistance to the circuit, it would skew all readings by that amount of resistance, which will likely throw codes since the resistance doesn’t change in a linear manner. Over heating the sensors will do nothing to alter the sensor’s reading long term.


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It reads temperature based off of impedance, while you could add resistance to the circuit, it would skew all readings by that amount of resistance, which will likely throw codes since the resistance doesn’t change in a linear manner.
I don't want to have a debate about this here but IMO you are wrong, the ECT sensor is a banal NTC thermistor and it has nothing to do with impedance, a resistance in parallel with it would reduce the overall resistance maintaining the reading curve as unlinear as it is but at a lower "level" hence increasing the ECT value calculated by the ECM, with an accurate calculation of the resistance the input can be altered with a resistor as the ECM to calculate +10 all the way which will reduce fuelling but as the real temperature is lower the combustion will not be optimal and the engine will produce less power... i made this trick myself long time ago to a BMW engine and i know exactly how it works, i dislike to do such things but my friend who convinced me to do it was interested only in fuel economy the power loss was no factor for him as the vehicle was hycomat and i couldnt refuse the man if you see what i mean

From the WSM:
ENGINE MANAGEMENT SYSTEM - V8; DESCRIPTION AND OPERATION 18-2-16
The ECT works as a Negative Temperature Coefficient (NTC) sensor. As temperature rises, the resistance in the sensor decreases, as temperature decreases, the resistance in the sensor increases. The ECT sensor forms part of a voltage divider chain with a pull up resistor within the ECM. Consequently as the ECT sensor resistance changes, the analogue voltage at the input signal from the ECT sensor to the ECM will be adjusted which corresponds to the temperature of the engine coolant. With this information, the ECM can implement the correct strategies for cold start, warm up, fuel injection, etc.
......
 

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It seems like a high value resistor in parallel would change the value of the thermistor only a little, which might serve to indicate a higher than actual temp. I say let him do it. Just don't buy any used cars from him.
 

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I don't want to have a debate about this here but IMO you are wrong, the ECT sensor is a banal NTC thermistor and it has nothing to do with impedance, a resistance in parallel with it would reduce the overall resistance maintaining the reading curve as unlinear as it is but at a lower "level" hence increasing the ECT value calculated by the ECM, with an accurate calculation of the resistance the input can be altered with a resistor as the ECM to calculate +10 all the way which will reduce fuelling but as the real temperature is lower the combustion will not be optimal and the engine will produce less power... i made this trick myself long time ago to a BMW engine and i know exactly how it works, i dislike to do such things but my friend who convinced me to do it was interested only in fuel economy the power loss was no factor for him as the vehicle was hycomat and i couldnt refuse the man if you see what i mean

From the WSM:
ENGINE MANAGEMENT SYSTEM - V8; DESCRIPTION AND OPERATION 18-2-16
The ECT works as a Negative Temperature Coefficient (NTC) sensor. As temperature rises, the resistance in the sensor decreases, as temperature decreases, the resistance in the sensor increases. The ECT sensor forms part of a voltage divider chain with a pull up resistor within the ECM. Consequently as the ECT sensor resistance changes, the analogue voltage at the input signal from the ECT sensor to the ECM will be adjusted which corresponds to the temperature of the engine coolant. With this information, the ECM can implement the correct strategies for cold start, warm up, fuel injection, etc.
......
I haven’t attempted to re-engineer the system, only thinking back to my BMW factory training on roughly how it works from 20 years ago. Only experience I’ve had with modifying ECT sensors was a few active autowerks supercharger installs back then that required changing one out, though I never took my scope to the new sensors to attempt to figure out in what way they were changing the value to the DME.

While fixing BMWs was fun, I’ve moved on long ago at this point and flushed much of that stuff out of my brain to make room for new data.
 

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Discussion Starter #10
Sorry I meant stop injecting gas into the engine
 

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The engine and its computer management is pretty complex and sophisticated. Even if you were able to convince the engine that the temp was higher than it actually is (which sounds less than practical), what other effects would it have on engine management?
 

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Discussion Starter #12
The engine and its computer management is pretty complex and sophisticated. Even if you were able to convince the engine that the temp was higher than it actually is (which sounds less than practical), what other effects would it have on engine management?
I was speculating it might result in better MPG. I'm getting less MPG than I was when the car was running at 195+. Land Rover programmed 195 for emissions reasons. If it thinks it's at 195 It will the same MPG and pedal responsiveness while operating at a lower temp to extend engine and head gasket life.
 

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you mentioned that your truck was running at these lower temps before... and it was getting better fuel economy then.

what's changed about engine management that you have restored the previous temps but it's not running the same?
 

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Discussion Starter #14
you mentioned that your truck was running at these lower temps before... and it was getting better fuel economy then.

what's changed about engine management that you have restored the previous temps but it's not running the same?
nothing, Just a feeling that it's 1-2 MPG less than before. I'm pretty in tune with it and the pedal feels less responsive then when it was running hotter.
 

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Well, you know that the engine needs to run at a real 195 or so to maximize efficiency. That means fuel economy and power, not to mention emissions. Fooling it to think it's at 195 when it's actually at 180 will reduce efficiency. So there's your trade-off. 195 or even 215 isn't too hot, so long as it goes no higher. I know you're trying to avoid head gaskets or slipped liners. The best way to do that is to not have bought a Disco in the first place. I knew it when I bought mine.
 

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Discussion Starter #16 (Edited)
Well, you know that the engine needs to run at a real 195 or so to maximize efficiency. That means fuel economy and power, not to mention emissions. Fooling it to think it's at 195 when it's actually at 180 will reduce efficiency. So there's your trade-off. 195 or even 215 isn't too hot, so long as it goes no higher. I know you're trying to avoid head gaskets or slipped liners. The best way to do that is to not have bought a Disco in the first place. I knew it when I bought mine.
Yes failure is what I'm trying to avoid. It would be different if my Rover only had one head gasket failure. But it had three. I'm trying to avoid a forth. The last time it failed the mechanic and the machine shop told me the block had been ground down 1mm under spec on one side of the block and therefore another HG failure was imminent. I bought new upper heads as they said it would help. The mechanic told me he used allot of gasket material glue or (or something) and "really pressed it in there hard to sandwich it as tight as possible" and hopefully that would work. So since then I've been paranoid about temps. The cost of the head failure isn't what concerns me .. its that someone unqualified will do it and other problems will come up or they will sabotage my Rover. Most of the people here roll their eyes at that but I've had mechanics do this before. One of them told me he wanted to buy the Rover from me for $5,000 cash. I politely declined. Then when I drove off the lot the water pump blew up and it had junkyard air springs installed. I took it into Sears and the mechanic told me the fan and pump were wobbling and one of the O2 sensors was different than the other. I called the guy up from Sears with the mechanic there demanding answers and he told me this 100% normal and the Sears guy was shaking his head. I had read about the front drive shaft failures and asked him to remove and inspect it. He charged me and never removed it ... and the front drive shaft U joint was barley hanging on by a thread ready to snap any second. The dealer in Merrit Island FL visibily showed me it had never been removed (totally covered in soot and oil no impact marks or finger marks) and the U-joint was worn out warped and about to break. When I called the original mechanic up demandig explanations - he said that nowhere in the book does it call for the front drive shaft to be removed only visually inspected.... Yet he charged me for removal and inspection.

If 90% of mechanics were honest I would not be so concerned about HG failure. I'd run it at 195 and save more $$$$ in gas vs. HG failure. It's all these experiences I've had with various mechanics that make me want to pay more $$$$$ using whatever means needed - to keep it out of their shops. Even the last place I tried to bring it to in Las Vegas tried to run a verbal con job on me to get $$$$$. The shops know it has a reputation as an unreliable money pit and want to profit off that. I know not all mechanics are like this. But it's like trying to find an honest lawyer.
 

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i think that maybe you see the world through your own special lens casting shades of impropriety on everybody that you see.

maybe your truck is slowly dying and these expensive recommendations are accurate

why don't you just get a TDi swap? it'll cost a bit of money, but you won't have to worry about this crap any longer, and it sounds like you're spending a lot of money anyway...
 

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Discussion Starter #18
i think that maybe you see the world through your own special lens casting shades of impropriety on everybody that you see.

maybe your truck is slowly dying and these expensive recommendations are accurate

why don't you just get a TDi swap? it'll cost a bit of money, but you won't have to worry about this crap any longer, and it sounds like you're spending a lot of money anyway...
I do not. And even if I did (cast shades of impropiety) it's irrelevant because it's a business. And I am not the only one if you read these forums long enough you will see others.

Yes but .... I can't get past the TDI engines being 4 cylinders. IMHO that is lame. If it was 8 cylinders I would be on the phone with them right now.
 

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Discussion Starter #20
Yes. We do.

And you are using the mechanic at Sears ...
Yes. On the road literally leaving the other guys shop. And even that mechanic at Sears was smart enough to know a wobbling fan/pully was not normal. The gall on this guy was unbelivable.I am literally on the phone as hes swearing up and down its normal and not to worry about it - while the Sears guy is shaking his head. It exploded shortly after. When I called him back asking him to make it right ... he claimed it was just a marvelous coincidence the water pump exploded after leaving his shop.... He said I had an old Land Rover that should be expected to have all kinds of problems. Indeed.
 
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