Hello Houston?
We have a problem.

The numbers on the engine block do not match the vehicle VIN.
Or am I misinterpreting them?

GM Tech Repair support reported the numbers on the left rear side of the block should be the
VIN: 4th to 9th #s
My VIN is 1GCHG35U231110297
HG35U2
H93023 ... so what is this??

The numbers I found are:
Drivers side:
2247H9302363 [last 4 digits are damaged; could be Z3S3] See below.

Even if I add a 1GC in front and 97 behind to get 17 digits. This does not come up in a VIN decoder.
INVALID VIN ...

I've tried variations on the last 4 digits that are scored and still nada.
2247H9302363
2247H93023S3
2247H930Z363
2247H930Z3S3
These also do not find anything w/ a Google Search. But that goes for 1GCHG35U231110297 as well.

Now I am really lost.
Thomas




Passenger side:
02247064793336800

 

The VIN comes up as a 2003 express using O’Reilly’s website -


VIN 1GCHG35U231110297 - copied from your post

Primary engine ID can be found by:

- The under hood emissions sticker (on underside of hood or on air filter housing).

- 8th digit (in bold above) of the VIN - U means it’s a 6.0 liter.

- RPO label (either in the glove box or on passenger side door jamb).

I wouldn’t get too worried about the numbers on the heads or block - they could be used replacements that were installed for a repair - could be a scrap yard special block assembly - whatever the reason, if the engine wasn’t the correct one for the vehicle, the PCM wouldn’t be able to run it.

Is there something specific you need to know?

 

Gumby22,

I am forgetting what the RPO label is supposed to tell me.
We have been banging on what IAC I can use on this van. There is nothing that is a qualified match.
So I know what the engine is supposed to be but given that there is no throttle body or IAC for it I am verifying the #s on the block against the VIN.

tbb2

 

Haha - didn’t notice the username or make the VIN connection at first.

RPO = Regular Production Options - each code refers to a specific system or sales destination - ex. C codes are for the HVAC system, J codes for the brakes, L for the engine and M for the transmission.

Sometimes these codes are needed when ordering certain parts (unfortunately not the IAC ). There’s a full list of definitions here - GM RPO Codes.

If the RPO label is missing (or painted over which happens a lot), a dealer should be able to provide a replacement with the VIN.

I’ve never had to decipher numbers on the heads, but the block casting number should be visible just behind the right cylinder head if you remove the doghouse. You can find more info about that here - Block casting #’s

I’m still digging on the IAC issue but my spare time is limited these days.

 

FYI, for your broken exhaust manifold bolt. At least yours has something sticking out of the head.
https://chevroletforum.com/forum/exp...d-bolt-116653/

 

Thank you ... I think.
Another thing to fix.

Any idea why these bolts are breaking off?

 

It's a known failure point on all LS engines throughout all years and I don't think they have fixed it yet. Heat cycles, differences in thermal expansion from iron manifold to aluminum head, poor grade fasteners, rust, hydrogen embritalment, all possible causes. They normally last long enough to get out of warranty which is all Chevy cares about.

I have some Fel-Pro blue bolts that have good reviews. It will take me a while to get around to doing the work. I'll do all new gaskets, plugs, and wires when I have time. The clamp seems to be working well for now.