Andy Kennedy

Newbie here, first ever Subaru

I've got the hatchback wrx Sti,

Why do they need mapping to make the engine safer? Could someone please put it in simple terms for me..

Still reading up and learning but there is a lot of info to take in.. I've got the cash to get it done if it means it will last me longer and save me money in the long run on repairs. I take pride in maintaining my cars and making sure they are kept to a high standard.

Also good places in the north west or close to get it mapped, willing to travel for the right garage!

Thanks

CharlySkunkWeed

iTrader: (7)

There was something to do with , when you over-rev the ecu cut the fuel , then (I'm sure someone will explain why) the piston **** itself.
The map suposidly did something to safeguard this.

CharlySkunkWeed

iTrader: (7)

https://www.scoobynet.com/scoobynet-...glands+failure

beanys

iTrader: (3)

I rang a Scooby specialist up when I bought my 08STI hatch 8 months ago ,and was advised not to get a remap as it would only put more strain on the engine and would not cure the failure if it was to happen

Currently on 51000 and running ok (touch wood)

Andy Kennedy

Cheers lads

This had a full engine rebuild 1200 miles Avon due to catastrophic failure of something, I have the receipt it's had everything done.. Plus a brand new turbo and clutch.. Seeing the bill I just didn't want to go through that in my ownership..

fat-thomas

iTrader: (4)

Unless it's been forged and uprated head bolts it will more than likely fail again.

Andy Kennedy

Thanks for the optimism.. 😂

What is it that causes them to fail then?

Tidgy

Exact cause isn't really known. Some people say the map. Others other things. The 2.5 is a bit of a dog. Subaru saved money by not putting proper forged pistons in it and crap headstuds. Swap out the rods pistons and headstuds plus head gasket and it will be good for 450.

bludgod

iTrader: (3)

there was a change in the map for the 08 cars - early cars had AZ1G201G with later ones getting AZ1G202G. Interesting differences between them seem to be:

Fuel table (part throttle transition onto boost - new rom goes richer sooner)

Throttle Angle map as you approach the rev limit (old rom holds power to 6600, updated rom starts to cut at 6200)

Rev Limit Fuel Resume - early rom has very high limit, updated rom has the more standard 9.67psi limit. This table controls when the injectors come back on after a rev limit trigger - however in some conditions bringing the fuel in too early could leave you a tad leaner than expected which could give rise to knock.

I think the combination of changes is what subaru were hoping would keep the pistons in one piece for a bit longer. If your running the older version of the software your dealer will likely be able to upgrade you to the newer one - or get the car mapped and your mapper should take care of these (power increase optional). Either way i'd start saving for the pistons tho

Andy Kennedy

Cheers buddy, I've just been to a local specialist and they are getting back to me with a date to map it.

bludgod

iTrader: (3)

cool stuph, I'm sure they know the above already but just double check for your own piece of mind that they upgrade you to AZ1G202G before they start tuning - look forward to seeing before and after charts

Andy Kennedy

Aye I will have a chat with th lad doing th work on Thursday. Will have to print this off, and let him read it.. Easier that way. My knowledge on these just now is minimal and I'm useless at explaining stuff I don't know about.. Will be doing a lot of reading over the next few months so I know more.