Be careful with generations. Gen I, Gen II, Gen III, Don't always mean the exact same thing. Pay attention to context.

There are variants within Ecotec RPOs, mostly depending on the year make model that they went into. I imagine that compression ratio variants might result in different pistons. Or did they accomplish that in the head? I have no idea. But at the end of the day, the most reliable way to know what an engine is, is the VIN of the vehicle in which it was originally installed.

Discussions about porous lost foam blocks (relatively rare) and later RPO EcoTecs using sand cast blocks seems to have created a perception that lost foam blocks are inferior generally. I don't think that is necessarily the case. Lost foam has the to potential to be more precise and allows some additional design possibilities. There were some changes to block design to add strength (and weight). Any simultaneous change to sand cast MAY have had other motivations, including supply chain factors. It may be that the best block designs for a particular application just happen to be sand cast, so that's how we make the distinction.

 

Sorry I've been gone, work has been insane.

Back with more data. Not going to post a ton of pics this time:

Year Make Model Displacement Engine Foam/Sand Stamp Code VIN

2.4 LEA or LAF Sand 10AHN N106150781
2008 Pontiac G6 2.4 LE5 Foam 10TCC S711051036 1G2ZG57B384188982
2006 Pontiac G6 2.4 LE5 Foam 10TAK S602230120 1G2ZF55B564251955
2012 Chevy Equinox 2.4 LEA Foam 10B1W M121161257 2GNALBEK3C1307566
2012 Chevy Malibu 2.4 LE5 Foam blank 1G1ZE5E07CF231521
2008 Pontiac G6 2.4 LE5 Foam 10TCC N806050715 1G2ZF57B484305651
2014 Chevy Equinox 2.4 LEA Sand 10A61 N141290688 2GNALBEK6E6346674
2014 Chevy Equinox 2.4 LEA Sand 10A61 N140691226 2GNALBEK4E6290637
2013 Chevy Equinox 2.4 LEA Sand 10A61 N122961576 2GNALDEK3D6300262
2012 Chevy Equinox 2.4 LEA Sand 10AKR N201251291 2GNFLNEK8C6264546
2007 Chevy HHR 2.4 LE5 Foam 10AWM S608230453 3GNDA23P07S545306
2008 Chevy Cobalt 2.2 L61 Foam blank 1G1AL18F087343087
2009 Pontiac G6 2.2 LE5 Foam 10ACS N810252047 1G2ZG57BX94199298
2012 Chevy Equinox 2.4 LEA Sand 10AKR N121530350 2GNALPEK3C1331590
2009 Chevy Cobalt 2.2 LAP Foam blank 1G1AK58H197287433
2014 Buick Verano 2.4 LEA Sand 10B9B N141350130 1G4PR5SK0E4220721
2010 Chevy Cobalt 2.2 LAP Foam blank 1G1AD1F52A7186031
2012 Chevy Malibu 2.5 LE5 Foam blank 1G1ZD5E03CF320649

Plus the all the previous data:

2006 Chevy Cobalt 2.4 LE5 Foam 10TAL S511070011
2011 Chevy Malibu 2.4 LE5 Foam 10TCC N005141568
2008 Chevy Malibu 2.4 LE5 Foam 10TCC S712050196 1G1ZH57B38F194951
2011 Chevy HHR 2.2 LE8 Foam blank
2011 Chevy Malibu 2.4 LE5 Foam blank
2011 Chevy HHR 2.4 LE9 Foam unknown
2012 Chevy Equinox 2.4 LEA Sand 10AKR N121642027 3GNBABDB3AS651167
2010 GMC Terrain 2.4 LAF Sand 10TPP N006180383 2CTFLCEW616402957
2.0 LHU Sand 10AFY N011032508
2.4 LAF Sand 10DM6 N151491107

So, looking at what we have so far, here are the trends I can notice so far:

• Every single stamping starts with 10.
• I have not yet found a 2.2L with stampings, but I have also found 2.4's with no stampings to that's not 100%. However, 100% of found engines with no stampings are foam-cast.
• Contrary to previous information, there seems to be no correlation between this code and the vehicles VIN.

If we look at the 3 letters after the 10 we get the following groups(so far)
LE5: AWM, ACS, TAK, TAL, TCC
LEA: AKR, A61, B9B, B1W
LAF: DM6, TPP
LHU: AFY

Still don't see any trends in terms of displacement or engine model based on any of these letters

I have found no further correlations, will continue gathering data and analyzing. If you see something let me know

 

My 2011 2LT is a 2.4 LE9 , still running strong at 228,000 miles. And almost 15 years of service!

 

I would greatly appreciate it if people could contribute the codes from their engines, it's super easily visible on the HHR! May need a little wire-brushing to be fully readable

I especially need data from 2.2L's, as so far every one I've found had no code stamped on the oil-filter housing.

 

Sorry my 2007 2.2 was an L61 by the RPO code sticker in the glove box ! It was sold in September 2019.
fastsuv might have some parts from it but #1 rod broke and put a hole in the front of the block. So, I don’t think he still has it!

 

Even with the broken rod and hole in the block, it still ran (rough but it ran).

Steve

 

Oldblue was a trooper! Even ran on 3 cylinders!

 

I'll take one off your 2.4 too, in just need as many as I can get

 

Just got done sorting another day's worth of data, got 40 cars worth. Two of which had remanufactured engines which some with their own special plate. Very cool, I'll include a pic.

2012 Buick Verano 2.4 LEA Sand 10AKL N112121474 1G4PP5SK5C4140382
2010 Chevy Cobalt 2.2 LAP Foam blank 1G1AB1F57A7111167
2006 Pontiac G6 2.4 LE5 Foam 10TAK S601260509 1G2ZF55B964241445
2010 Chevy Malibu 2.4 LE5 Foam 10TCC N911031842 1G1ZC5EB3AF160418
2012 Buick Verano 2.4 LEA Sand 10AKL N120441270 1G4PR5SK1C4160719
2015 Chevy Equinox 2.4 LEA Sand 10DM6 N142050769 2GNALBEK4F6117296
2003 Saturn Ion 2.2 L61 Foam 10RFC S303120612 1G8AL52F83Z185788
2013 GMC Terrain 2.4 LEA Sand 10A61 N123350968 2gkalmek5d6228350
2005 Chevy Cobalt 2.2 L61 Foam blank 1G1AK52F157556080
2003 Saturn Ion 2.2 L61 Foam 10RNC S303190175 1G8AF52F83Z168142
2011 Chevy Malibu 2.4 LE5 Foam blank 1G1ZC5E11BF141049
2005 Chevy Cobalt 2.2 L61 Foam 10RPC S212100430 1G1AL52F457646059
2013 Buick Verano 2.4 LEA Sand 10B9B N122821141 1G4PP5SK1D4135231
2011 Chevy Malibu 2.4 LE5 Foam blank 1G1ZC5E19BF342763
2009 Chevy Malibu 2.4 LE5 Foam 10AAM N810131955 1G1ZG57B094188461
2002 Pontiac Grand Am 2.2 L61 Foam blank 1G2NE52F22C257477
2014 Chevy Equinox 2.4 LEA Sand 10A61 N132323259 2GNALCEK0E6113136
2017 Chevy Equinox 2.4 LEA Sand 10DM6 N163120211 2GNFLEEK5H6236419
2015 Buick Verano 2.4 LEA Sand 10B9B N142320072 1G4PP5SK7F4110336
2006 Saturn Ion 2.2 L61 Foam 10TYD S507290841 1G8AL55FX6Z118867
2009 Saturn Vue 2.4 LE5 Foam 10AAB N81027156 3GSCL33P49S580538
2013 Buick Verano 2.4 LEA Sand reman 1G4PP5SK0D4191709
2014 GMC Terrain 2.4 LEA Sand 10A61 N132200537 2GKFLWEK3E6102409
2016 Chevy Equinox 2.4 Sand 10DM6 N153501199
2010 Chevy Malibu 2.4 LE5 Foam 10TTC N910200609 1G1ZC5EB8AF155909
2008 Pontiac G5 2.4 LE5 Foam 10TBB S707230454 1G2AN18B287113294
2009 Pontiac G6 2.4 LE5 Foam 10AAM N808060910 1G2ZG57B894133302
2011 Chevy Equinox 2.4 LAF Sand 10AHN N101251160 2CNFLNEC0B6360473
2006 Chevy Cobalt 2.2 L61 Foam blank 1G1AL55F967697179
2012 Chevy Malibu 2.4 LE5 Foam blank 1G1ZC5E06CF230012
2008 Pontiac G6 2.4 LE5 Foam 10TCC S711200475 1G2ZG57B984178778
2010 Chevy Malibu 2.4 LE5 10TTC N005071092 1G1ZD5EB6AF293770
2004 Saturn Ion 2.2 L61 Foam 10REE S310100344 1G8AN12F04Z148349
2005 Chevy Cobalt 2.2 L61 Foam blank 1G1AL12F657615713
2009 Saturn Vue 2.4 LE5 Foam 10AAB N810290222 3GSCL33P59S580225
2003 Chevy Cavalier 2.2 L61 Foam blank 1G1JC12F337373668
2010 Chevy Equinox 2.4 LAF Sand reman 2CNALBEW7A6227954
2012 Chevy Equinox 2.4 LEA 10AKR N12061151 2GNFLEEK2C6299020
2013 Chevy Equinox 2.4 LEA Sand 10A61 N122330832 2GNALPEK4D1134333
2009 Pontiac G6 2.4 LE5 Foam 10AAM N901070232 1G2ZJ57B094237865
2005 Chevy Malibu 2.2 L61 Foam 10UZJ S502161675 1G1ZS52F75F260232

Key takeaways: I finally found a few 2.2s with stampings, although they are all pre-'07 L61s. Also I found a few GM remanufactured engines which include the date of reman.

I was really hoping this would be enough data because this was a tiring day but I'm still finding new codes so I have to keep going. Also I haven't found a single LSJ or LNF so I don't have any data from those yet

L61: REE, RFC, RPC, TYD, UZJ, blank
LAP: blank
LE5: AAB, AAM, ACS, AWM, TAK, TAL, TBB, TCC, TTC, blank
LEA: A61, AKL, AKR, B1W, B9B, DM6
LAF: AHN, DM6, TPP
LHU: AFY


2022 engine in a 2013 Buick Verano



2015 engine in a 2010 Equinox

 

A remanufactured in 2015 engine in a 2010 equinox