To decode a Citroen C5 engine number, you can use the following table:
First Two Characters | Engine Type
------------ | --------------
DV | 2.0-liter HDi diesel
DW | 2.2-liter HDi diesel
EW | 2.0-liter 16V petrol
EP | 1.6-liter THP petrol
TU | 1.4-liter petrol
Third and Fourth Characters | Year
------------ | --------------
01-09 | 2001-2009
10-19 | 2010-2019
20-29 | 2020-2029
Fifth and Sixth Characters | Month
------------ | --------------
A | January
B | February
C | March
D | April
E | May
F | June
G | July
H | August
I | September
J | October
K | November
L | December
Last Four Characters | Serial Number
------------ | --------------
0001-9999 | Unique serial number for each engine
For example, if a Citroen C5 has an engine number of DV4E12345678, the engine code would be DV, which indicates that it is a 2.0-liter HDi diesel engine. The production code would be 4E, which indicates that the engine was manufactured in April 2014. The serial number would be 12345678, which is a unique number for that particular engine.