How to check and change td5 injector codes

Having performance problems that nobody could explained, I checked my injector codes in the hope that it would explain the difficulties the engines had to rev and its lack of power.

In order to check injector codes, you'll need a nanocom or equivalent and you'll need to access the injectors. To do so, remove the rocker cover (as explained in a previous post).

Once the cover is off, write down the injector codes (injector 1 is the one nearest to the front of the car). They are made of letters and digits. You'll notice that they are groupped into 2 groups of 2 letters, then a single letter/digit, then a digit below, and another farther to the right. Here is a diagram:


The important parts are the 2 groups le 2 letters and the following letter/digit. The other digits can be ignored.

According to the nanocom documentation, there are 3 types of injectors. Each type with a different series of letters/digit after the 2 groups of 2 letters. I think they are adjustments the ECU needs to make according to injector tests made at the factory. These 3 types have some corresponding codes:
Type 1/Type 2/Type 3
C/M/0
A/E/1
B/F/2
C/G/3
*/H/4
*/J/5
etc

Assuming you use a laptop, you need to enter the codes in the settings section:


First read the engine settings from the ECU (press "read settings"). Then change the codes (on a laptop by pressing the "write settings" button). Once you inject the last code into the ECU (and read them back by pressing the "read settings" button), the nanocom displays the equivalent codes for the 3 injector types. It looks like the nanocom changes the codes you type, but in fact it only displays correspondances for all injector types. You only need to check that the last code you typed (the single letter or digit) appears in the list of 3 characters displayed in the textbox.

Examples: one of my injectors has code NB BL A 2 O. 2 and O can be ignored. Once I inject NB BL A, the nanocom displays:
NB BL 1-E-A
because A corresponds to E and 1 in other injector types.
An injector with code NN DH J becomes:
NN DH 5-J-*
because J corresponds to 5 in type 3 injectors, and type 1 injectors don't have a match (hence the *).

(c) Cedric Raguenaud