CE Lancer ECU tuning

Hey guys
Awesome read - I now know more about CE ECUs than I ever thought I would!

My questions:

-2003 Mirage
-Looking at a JDM 4G15 DOHC engine/head swap
-Want to reflash my stock ECU to suit
-Can it be done?
-Who would be the reflash/dyno tune gurus to use in Melbourne?

It seems the 'key' to all this is having the correct 'definition file' to read the ROM image downloaded from the ECU. Does anyone have a definitive resource for the definition files? How do I determine which definition file is required for my particular ECU?

Need a workshop recommendation as I'm not looking to DIY

Many thanks!
 
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You’re spot on about the definition being the key. A 2003 will likely have a plastic case ECU which is tune-able. You can certainly flash it yourself or have someone tune it and reflash it professionally.

The definition file required is determined by your rom ID. This is stored internally and is readable/flashable/changeable to an extent. Someone might know what ROM is inside by referring to the external part number, but I certainly don’t!

Being as you said you’re not looking to DIY, I’d focus on finding a workshop that can do this work for you. Primary focus would be on the tuning side if you’re deadset on sticking with a factory ECU.

The further away from stock you take the engine, the harder it is to retain all those stock features and niceties through the stock ecu. I would personally encourage you to find a workshop that is interested in tuning your dohc g15 and work with their preferred interface for tuning.

Also being as a dohc 4g15 will only need fuel map tuning there are several inexpensive ecu options at your disposal. You certainly wouldnt need anything with as many outputs as a haltech for example
 
SDate42 said:
You’re spot on about the definition being the key. A 2003 will likely have a plastic case ECU which is tune-able. You can certainly flash it yourself or have someone tune it and reflash it professionally.

The definition file required is determined by your rom ID. This is stored internally and is readable/flashable/changeable to an extent. Someone might know what ROM is inside by referring to the external part number, but I certainly don’t!

Being as you said you’re not looking to DIY, I’d focus on finding a workshop that can do this work for you. Primary focus would be on the tuning side if you’re deadset on sticking with a factory ECU.

The further away from stock you take the engine, the harder it is to retain all those stock features and niceties through the stock ecu. I would personally encourage you to find a workshop that is interested in tuning your dohc g15 and work with their preferred interface for tuning.

Also being as a dohc 4g15 will only need fuel map tuning there are several inexpensive ecu options at your disposal. You certainly wouldnt need anything with as many outputs as a haltech for example
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Thanks for the reply!

So how is the ROM ID initially determined?

I’d literally just be tuning to suit the DOHC head air/fuel requirements, hence reflashing the original ECU seems the best course of action, to retain all the factory niceties as you say?
 
My basic question here is - can a qualified workshop with EVO experience tune my 4G15 ECU with their existing equipment/software - or are there software differences with the 4G15 that would throw a spanner in the works?
 
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Mirage85 said:
Thanks for the reply!

So how is the ROM ID initially determined?

I’d literally just be tuning to suit the DOHC head air/fuel requirements, hence reflashing the original ECU seems the best course of action, to retain all the factory niceties as you say?
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From what I know the Rom ID is just “made up” by Mitsubishi. Much like you might decide to call a son Bob or Larry. There is probably some technical procedure and legitimate naming structure but I don’t think it matters so much.

Mirage85 said:
My basic question here is - can a qualified workshop with EVO experience tune my 4G15 ECU with their existing equipment/software - or are there software differences with the 4G15 that would throw a spanner in the works?
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You’d have to find out on a shop by shop basis - just give them a ring, tell them you have an mirage 03 mirage and you’re looking to get a reflash done to suit a dohc head. They’ll be able to tell you yes or no and why. I imagine if they tune evo’s there’s not too many reasons why not a mirage.

It may be expensive due to the shop needing time to make or find a definition and then the dyno time required. But again that’s going to be a shop by shop basis and the only way to know is to call them up and have a chat.
 
SDate42 said:
You’d have to find out on a shop by shop basis - just give them a ring, tell them you have an mirage 03 mirage and you’re looking to get a reflash done to suit a dohc head. They’ll be able to tell you yes or no and why. I imagine if they tune evo’s there’s not too many reasons why not a mirage.

It may be expensive due to the shop needing time to make or find a definition and then the dyno time required. But again that’s going to be a shop by shop basis and the only way to know is to call them up and have a chat.
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Yes - already shopping around. Have spoken to two shops experienced with Evos, and they're 'fairly sure' it's possible and 'should be' straightforward given it's the same basic ECU architecture - but there's still a bit of doubt there.

It would be great to hear from someone who has had their 4G15 ECU tuned by a shop...
 
ROM ID is a hex code, not 100% on how they get it, but its a unique-to-each-model number located in the first few bytes in the ECU hex code.

The g15 DOHC mightttttt be fine on the stock g15 ecu tuning at a glance. The ECU can adjust up to about 7% each way from "perfect", which may be enough for the stock ecu to adjust, at least to get it to the fine-tune stage. Any shop worth their weight that touches Evos will be able to fix it with minimal effort though, but that depends on if you want to go with "let OEM adjust", or ground up retune.
 
donki said:
ROM ID is a hex code, not 100% on how they get it, but its a unique-to-each-model number located in the first few bytes in the ECU hex code.

The g15 DOHC mightttttt be fine on the stock g15 ecu tuning at a glance. The ECU can adjust up to about 7% each way from "perfect", which may be enough for the stock ecu to adjust, at least to get it to the fine-tune stage. Any shop worth their weight that touches Evos will be able to fix it with minimal effort though, but that depends on if you want to go with "let OEM adjust", or ground up retune.
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It’ll definitely control the engine to a degree, but with questionable success.

I recall @barreh13a ran his DOHC head on the stock tune, but kept popping head gaskets, and the theory was excess heat caused by lean running.
 
Ok this might be an easier one to answer

Tuner has suggested he plug his equipment in to see whether or not he can - but he's asked me to confirm if the Mirage/4G15 OBD pinout is exactly the same as Evo/4G63?
 
As far as I am aware, yes. He’ll be looking for the odb2 port and the flash connector. This is white and likely tapped out of the way - it’ll be near the odb2 plug.

Check in your car and have a look for the white flash connector.
 
SDate42 said:
As far as I am aware, yes. He’ll be looking for the odb2 port and the flash connector. This is white and likely tapped out of the way - it’ll be near the odb2 plug.

Check in your car and have a look for the white flash connector.
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Yes - both visible in my car

He was concerned that if the pinout is different, he could cause damage when trying to apply ‘evo’ software to my car…
 
On the odb2 plug they are the same. ECU pinout is different - you can chase that up with a google search. Bit for reference there was only two pins different on my CH ecu and an evo7/8 one. Neither mattered for tuning.
 
Yes and no - Its the almost exactly the same for OBD, being on-board diagnostics, but certain diagnostic functions are encoded different for a CE compared to the Evo, despite being the same at the ECU's microcontroller level. This i assume is because they developed the core ECU functionality, and then added additional functions like wastegate control for the Evo's.
The actual pinouts of the ECU to the sensors and hardware is different, so while you can use Evo "software", there will be a handful of things that need to be checked to see if it'll convert across properly - one example is a 3pin TPS or a 4pin TPS, and the correct way is to convert it across, you can also tune it with the other TPS's settings (though, this is exactly the same as like you said barreh13a's DOHC.
 
Hi guys, not sure if this thread is still active but looking for some help with a stock ECU that is re-learning after a battery swap. All is good except low idle while coasting. While stopped at the lights no issues but when I have it out of gear and rolling, idle is real low and sometimes engine stalls. 4g15

Any advice is appreciated.
 
No power steer said:
Hi guys, not sure if this thread is still active but looking for some help with a stock ECU that is re-learning after a battery swap. All is good except low idle while coasting. While stopped at the lights no issues but when I have it out of gear and rolling, idle is real low and sometimes engine stalls. 4g15

Any advice is appreciated.
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We're still somewhat active!

The stock ECU "learns" or adjusts via only one or two processes, but these processes adjust a few options. Idle while coasting is a very uncommon circumstance however.

Generally the fueling is adjusted in four batches, lasting 4 minutes long. This happens on the first start and run of the car after battery reconnect, but also adjusted every time you run the car. Its just that when the battery is disconnected, there is zero history so the self-adjustment is more dramatic than a car thats had 200 starts without battery disconnect.

The best way to set a good baseline is the following (jump into the sequence where you see fit, but to start clean i suggest start at 1):
- disconnect the battery
- turn the key to discharge any power
-reconnect the battery
-start the car, dont touch the accel, and let it idle for at least 16minutes, minimum
- get the car to cruising speed (50kmh, 60kmh, 100kmh), and drive it for at least 16mins, minimum, and avoid heavy accel. A freeway is best for this, as you need to try to stay under 80% throttle the whole time.

The above is one cycle for idle, and one cycle for cruise. If youve done it once, you dont need to disconnect the battery, and can just drive like normal. The more cycles you do, the "cleaner" the idle and cruise should be.
 
donki said:
We're still somewhat active!

The stock ECU "learns" or adjusts via only one or two processes, but these processes adjust a few options. Idle while coasting is a very uncommon circumstance however.

Generally the fueling is adjusted in four batches, lasting 4 minutes long. This happens on the first start and run of the car after battery reconnect, but also adjusted every time you run the car. Its just that when the battery is disconnected, there is zero history so the self-adjustment is more dramatic than a car thats had 200 starts without battery disconnect.

The best way to set a good baseline is the following (jump into the sequence where you see fit, but to start clean i suggest start at 1):
- disconnect the battery
- turn the key to discharge any power
-reconnect the battery
-start the car, dont touch the accel, and let it idle for at least 16minutes, minimum
- get the car to cruising speed (50kmh, 60kmh, 100kmh), and drive it for at least 16mins, minimum, and avoid heavy accel. A freeway is best for this, as you need to try to stay under 80% throttle the whole time.

The above is one cycle for idle, and one cycle for cruise. If youve done it once, you dont need to disconnect the battery, and can just drive like normal. The more cycles you do, the "cleaner" the idle and cruise should be.
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Thanks Donki, I will give this a shot. I live quite close to work so i rarely get a chance to cruise it. I will try tonight on the freeway as I finish late and it should be relatively void of traffic. I did a test in a large empty Carpark this morning and found it will stall consistently if I coast to a stop. Almost as if the car believes it IS in gear when it is NOT. Stalls at the point where I would expect it to if the car was in gear.

98 Ce mirage
Manual
4g15 320,000ks
No power steering from factory
No abs
Drum brakes on rear
No safety features
Exciting to drive because if you make a mistake you die.
Starts first time every time.
Serviced every 5000k
only ever 98 in the tank
New plugs regularly
New leads
Fresh trans oil very recently

Never had this issue before. Used to idle a little high actually.

Thanks again
 
Donki you are a true legend and a credit to this community. Took it 20 mins up the freeway and 20mins back. Took it for a putt-putt around after testing the coasting to a stop. Low idle is gone! No stalling.

I took it for a quick up and down the freeway after I put the battery in but I wasn't cruising as there was traffic. Tonight I could pick a speed and stay on it. Seems as though this is what it needed.


Thanks again for your help.
 
Most welcome mate. The more 4x4 groups you do, the cleaner it should get. The ECU are near 25year old tech now, so they will get hiccups every so often, but generally speaking that process will reset most of em.
 
Saludos, necesito encontrar archivos de rom y definiciones para mi carro, un lancer año 2000, motor 4g93, la ecu es MD353929 y el chip es MH7202F. Espero su ayuda y saludos desde Chile!
 
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