Mitsubishi Engine Serial Numbers
Why would the dealer have to disclose the engine had been replaced/rebuilt? Unless they specifically said it's the original longblock, or you purchased the car brand new. In the province of ontario you have the declare whether it's a rebuild verbally and on the bill of sale.
Mitsubishi Engine Serial Number Location
If not they can be fined if proven. There's no accurate way a dealer can sell me a car with 'true' kilometers because the engine could have 200k on it.
The fact of the matter is, they breached the contract and probably didn't know it. Thank you fostytou!
I decided it would be a good idea to compile an as complete as possible list of Mitsubishi engine codes. This way when someone asks, 'What the heck is a 4Gxx?' , we might actually have an answer. As of yet I don't know how extensive the info on each motor should be, so I'm open to suggestions. I also don't know if I want to list every possible variant of each motor, since something like the 4G63 has a lengthy list.
The list will be far from complete from the get go, so please feel free to post a motor and all the info you know. Also, feel free to correct any erronious info, just don't get offended when it gets deleted after I use it. For Starters: Reading Mitsubishi Engine Codes. Here's a breakdown on what some of the engine codes look like and mean. Example: 4G61T (1.6L I4 turbo motor in the Colt/Mirage turbo) 4 = 4-cylinder G = Gasoline, Iron Block. (D = Diesel ie 4D65) 6 = Engine Series 1 = Engine Model (Doesn't equate to capacity, as a higher number can belong to a lesser cc'd engine.) T = Turbo (This is more of an adopted addition to the engine codes, rather than an official part of it.
The official way Mistubishi will list the motor is '4G61 Turbo'.) Example: 6A13TT (2.5L V6 twin-turbo motor in the Galant/Legnum VR-4) 6 = 6-cylinder A = Gasoline, Aluminum block 1 = Engine Series 3 = Engine Model TT= Twin-turbo Mitsubishi Engine Code Reference Chart 4D55 - 2.3L. Found in Galant 2.3 TD (A167) as well as Pajero (Shogun) 2.3 TD 4D56 - 2.5L. Used in Pajero (Shogun) 2.5 TD (L049G) 4D65 - 1.8L. Found in Galant 1.8 TD (E34A) 4D68 - 2.0L, 1998cc 4G11 - 1.2L, 1244cc 4G12 - 1.4L, 1410cc 4G13 - 1.3L, 1248cc 4G15 - 1.5L, 1468cc 4G16 - 1.2L, 1198cc 4G18 - 1.6L, 1583cc 4G30 - 1.3L, 1298cc 4G31 - 1.5L, 1499cc 4G32 - 1.6L, 1597cc 4G33 - 1.4L, 1439cc 4G35 - 1.7L, 1686cc 4G36 - 1.2L, 1238cc 4G37 - 1.8L, 1755cc 4G41 - 1.4L, 1378cc 4G42 - 1.2L, 1187cc 4G51 - 1.9L, 1855cc 4G52 - 2.0L, 1995cc 4G53 - 2.4L, 2384cc 4G54 - 2.6L, 2555cc 4G61 - 1.6L, 1597cc. Came available with turbo and naturally aspirated versions. Most are DOHC, but apparently SOHC versions were used.
4G62 - 1.8L, 1795cc 4G63 - 2.0L, 1997cc. Came available with turbo and naturally aspirated versions.

Most are DOHC, but apparently SOHC versions were used. Mostly available as a SOHC, there are DOHC versions available. 4G67 - 1.8L, 1836cc 4G69 - 2.4L.
Mitsubishi Engine Serial Numbers List
Motor is a SOHC MIVEC 4G92 - 1.6L, 1597cc. Known commonly for it's DOHC MIVEC version used in the Mirage. 4G93 - 1.8L, 1834cc. Available as a non-turbo SOCH and DOHC. DOHC turbo version was available in '92+ Lancer GSR. Newer SOHC motor used in the Lancer.
6A10 - 1.6L 6A11 - 1.8L 6A12 - 2.0L. Mostly known to be a DOHC MIVEC used in the FTO. Was also availabe in a twin-turbo version in the early 7G Galant VR-4's. Was commonly a DOHC twin-turbo motor used in the more modern 7G and 8G Galant VR-4's.
6G71 - 2.0L, 1998cc. Only known variant is SOHC and supercharged. 6G72 - 3.0L, 2972cc.
This motor came in various forms, including SOHC and DOHC naturally aspirated versions. A DOHC twin-turbo version was also available in the 3000GT/GTO VR-4. 6G73 - 2.5L, 2497cc. Available naturally aspirated in SOHC and DOHC form. Available naturally aspirated in SOHC and DOHC form. Available naturally aspirated in SOHC and DOHC form. G15B - 1.5L SOHC 12v Carb found in early Mirage and Precis.
Came as a SOHC turbo. Found in early Montero and Truck. Came as a SOHC turbo.
Came as a SOHC sometimes with turbo. Found in JDM Starion as well as the Cordia and Tredia. SOHC found on the early Galant and Expo. If you're looking for a reference list of Hyundai Motor Codes and their Mitsubishi Equivelants, here's the link.