Td5 Wastegate Modulator and Pressure Limiter

by **defender2015** » Wed Jun 10, 2015 6:25 pm

Hey there! I was wondering if anyone knows the address for the Wastegate Modulator map (if it exists, I think so) on an NNN000120 ECU (Disco II and Defender). Also, it is known that the engine will go to limp mode at around 1.28 bar boost pressure, is there any place in memory where we could change this limit? Thanks!

by **Doc77** » Fri Jun 12, 2015 3:44 pm

Hi,

I think you have to tune the wasgate manually by turning the screw (and counterscrew that is locking it). turbo is not controled by ecu on this engine...

by **defender2015** » Sat Jun 13, 2015 3:52 am

Thanks for your reply! I do know that, and I know that the most common option to increase the allowable boost pressure is to "fool" de ECU by manipulating the signal from the MAP sensor, but I heard somewhere that it would be possible to increase this limit via the software, maybe someone would show us how :) Actually on the Disco II and Defender post 2002 (I think!) there's a wastegate modulator (basically it allows the ECU to influence the behavior of the wastegate valve) and I was hoping it would be controlled by some map. I just don't know which one!

by **andyham** » Sat Jun 13, 2015 7:15 am

Hi, I have been looking for exactly the same information.

Once the MAP sensor reads 5v which according to my Nanocom = 1.4 bar boost then the ecu trips into a reduced fuelling mode which limits boot pressure to 1.0 bar max. The infamous Limp Home mode. Using TD5 Map Editor software I was hoping to see a specific reduced fuel mode that was being used but all 4 fuel maps that I can see are very similar, therefore I suspect my logic is flawed somewhat.

Other than that, trying to decipher each of the esotic maps to find the trigger for that 5v MAP input is elusive so far.

Anyone who can help with the map address deciphering or any specific knowledge of the exact mechanism to trigger the boost limit within the ECU would be most helpful.

cheers
Andy

by **defender2015** » Sat Jun 13, 2015 9:27 pm

Yap, done that too, no great conclusion. But I do know now that the four different maps are supposed to be selected depending on ambient conditions like atmospheric pressure and temperature. Regarding the limit, some say the ECU will enter "limp mode" when the sensor's output is near 4.75 V, maybe one could get a MAP sensor with different scaling properties such that a higher pressure would produce less voltage (and greater max readable pressure), and then correct every table that uses this signal (same for MAF sensor) hence rising the limit! What do you think?