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I've done the following tonight for a Z32 for a workshop, rather than modifying the loom. Any comments please let me know. Need to find a valid value for the fuel pump resistor to stop the DTC

For anybody needing the resistor value to fake out the fuel temp sender, I did some bench testing and 2K works just fine. Giving 25 degrees.

This will be in the new version of the document anyway.

PL

Petes updated version 2 with the resistor value

Knock sensing?

Just to clear something up for me. I've wired mine in with a field harness and I'm only using one knock sensor. If two share the same signal wire, would it affect the signal?

Fuel temp though is exactly the same resistance as the water temp sender. I joined mine into that and due to sharing one feed the temp is out by around 20degrees but the codes have gone.

Hi Andy,

I suspect the knock sensor thing won't really matter. One of the local guys has tried it using both wired together and reckons it works fine. I haven't personally tried it but I suspect either method would work.

I'm not of the same opinion on the coolant temp sensor idea though. I've heard of other people doing this but I wouldn't recommend anything that affects the coolant temp reading that the ECU sees.

This has gotta be a bad thing because the coolant temp is used for many calculations within the ECU. So you want it to be right. I'd go grab a 5c resistor and be happy I reckon.

PL

whats the best resistor to put in. ???watts/???ohms I've seen the numbers vary so just wired it up to the temp sensor

2K. Watts doesn't matter cos there's bugger all current. Grab a 1/4W most probably - but only cos they're the most common size.

PL

I've putted such resistor but fule temperature is like 78 and DTC code always appear.

I've wired fuel temp pin to resistor and resistor to the ECU ground pin is it 2000 Ohms resisotr or 2K its something different?

And another thing. I thinck my knock sensors are bad now. Car always jumps to knock maps even without reaching half load. I've retard ignition 2 degres later and it anyway jumps to knock maps usually. I heard there is a solution of putting Resisor in place of knock sensor?

the fueltemp is only used/monitored at engine start in the Z32 code and is used to switch a solenoid on/off.
Best is to keep it around 20-30C using a resistor.

If there's any interest, I can modify the Z32 code so the fueltemp is no longer used at all and won't throw a DTC.


> I heard there is a solution of putting Resisor in place of knock sensor?

yes, bypass it with a 1 Mohm resistor

-Eric

Hey Eric,

Sounds like it might be a handy code mod for the guys running Z32 ECU's in their R33's. Which is becoming mighty popular!

PL

Whoa i guess thets the problem of my cold starts. I'm having realy problematic to start engine after night and its only -10 - -15 here at night. I'm covering my car with tent. A code to not monitor fuel temp will be great.

> Sounds like it might be a handy code mod for the guys running Z32 ECU's in their R33's. Which is becoming mighty popular!


Ok, here's one of my custom ROM's.

"special" features are:

-EGR disabled (software code removed)
-FUELTMP disabled (software code removed)
-FUELTMP DTC disabled
-CHECKENG MOD (check engine lamp on dashboard will turn on as soon as ECU starts reading from low octane maps, eg. because of detonation)
-Modified knocksensor sensitivity to prevent it from detecting false knock ( R33)

-realtime read of register addresses below $0140 (advanced users)


this particular ROM can be used for a R33 GTST (RB25DET), but with the right maps/tables it can be used for a Z32 as well.


USE AT OWN RISK !


-Eric

Great work! Downloaded.

Hey Eric,

Awesome work. I'll give that a go when the opportunity crops up. I particularly like the indication when knock maps are accessed.

Unfortunately I did a Z32 ECU > R33 last Friday. Would have been good to try your modified code - bad timing! Not to worry. There'll be others - lots of R33 owners wanting to tune their cars here. Just need a good source of Z32 ECU's now - they're getting thin on the ground here.

Thanks heaps for your efforts. They are appreciated. I know how long that dissasembly stuff takes...

Merry Xmas!
Pete L

nice work guys and Merry Xmas to all of you

by the way, does it matter whether its an RB25DET Series One or Two Engine?

Ive noticed (only on Series 2's thought im due to plug into a Series 1 on wed afternoon) that when I plug in the ECU , yep its starts fine, perfect in fact

However, when I go to Rev the engine (stationary) it fails to rev cleanly, in fact it will hardly rev at all

I used the ENT file off this thread here too

any tips? or queries to what I might be doing wrong ?