I bypassed my det sensor with a resistor about 6 months ago and got rid of the code 34. I have had a new engine fitted since then and have been told that the sensor was working fine on it before it was removed from the other car.

 

I was at Zfest the other week and was told that with the resistor fitted it will get rid of the error but the ecu will still know the difference as the sensor normally gives different resistances, not the constant 1k ohms. He also said that it will still run safty boost and the timing will be retarded.

 

I have a boost controller which overrides the safty boost but I'm worried about the timing being retarded due to this. i asked him to check the timing on the consult to confirm but he said the the consult only reads what the ecu expects, not the actual timing?

 

Now i know that the resistor will bring a normal car out of safty boost as so many people have proved so he is wrong there but anyone know about the timing / maps the ecu will use (JD chipped ecu).

 

I could reconnect the sensor now as I should have a working one but is it worth the bother?

I can't send a PM for some reason :S If the knock sensor isn't connected to the ECU, how can it detect knock? The whole idea behind using ECU's instead of distributors is that the optimum values can be calculated to suit engine and enviromental conditions. An engine management system that has ignition inputs will surely advance ignition angles to an extreme if the knock sensor isn't providing a signal in reference to pinking. When the ignition angle reaches a threshold, the ECU will have to refer to its base settings/maps.

andy (at) zxtreme.co.uk - redo it to form a proper address and mail me lol

im finding this an interesting debate,,, can you not continue it here?

>> An engine management system that has ignition inputs will surely advance ignition angles to an extreme if the knock sensor isn't providing a signal in reference to pinking.

 

This is not the case in the Z32 ECU. (and quite a few other Nissan ECU's like the ones used in the R32, R33, S13, etc).

 

the ECU will NEVER advance the ignition by itself over the levels as specified in the ignition maps.

 

-Eric

^^^ Just been looking at actual ignition values from a stock z32 and compared them to stock igniton maps. The actual angle in some cases was more than 7 degrees over advanced than stated in the maps for all loading situations in relevance to engine speed

were you using realtime map tracing ?...in other words, you knew exactly what cells in the map the ECU was reading ?

 

The ECU uses interpolation to calculate the actual value, as rpm and engine load are never really exactly as what is specified in the map scales.

Because of this it reads the value of 4 adjacent cells at once and basically averages these 4 cells.

This can explain a higher value...

 

without realtime tracing there's no way you can accurately "guess" what cells it was reading, unless you have set all cells in the map to 1 value.

dude its 5 in the morning!