Snels 4G93 swap

Snel

New Member
Backstory: I've been helping a mate with a 4g93 swap into a CE mirage over the past couple months and due to neither of us having a lot of time and hes given up on it. I will be taking it from him if we can get it going soon so that I can drive it to mine before the rego runs out. I have done the swap before as I helped Lachie "Doomslayer" with his swap last year as well as replacing the 4g93 he cooked.

The source of the problems we have run into has revolved around both cars having there engine looms molested by previous owners. On top of that the 4g93 is a slightly older model 4g93 than the 2 4g93s I worked on in Lachies car. Meaning that the looms are slightly different between the my mates lancer and mirage. I had to splice in some wire to use the front loom from the mirage on the lancer for the starter motor to be wired up correctly.

The point we are stuck at is that the immobilizer is not happy (have a engine light) and we aren't getting injection or the fuel pump to turn on. The car turns over and we are getting spark, can get it to run with start ya bastard (sounds rough as hell coming out of the headers).

So far what we have done since fixing the problems causing the car to not even turn on, then not turn over is:
  • We have left the key in the on position for an hour with both immobilizers but neither removed the engine light.
  • Powered the fuel pump directly and it works and pumps fuel. Still car wont start.
What we are worried about is that the loom in the donor lancer was very molested around the interior fuse box with all sorts of wires spliced in seemingly to connect a "shock sensor" and a siren which was in the engine bay. We had the thought that potentially the car was stolen and that the molesting was a work around the immobilizer.

Our next plan is to grab the ecu, immobilizer, key reader and key from Lachies car and see if that will start the car. Question is whether his ecu will start out 4g93 considering the slight differences in his 4g93 and ours.
 

donki

Administrator
Forum Administrator
As long as the ECU is replaced with another of the same material (metal case for metal case, or plastic case for plastic case), it should be fine.

Key + imob + ECU must be from the same car. If you mix and match it wont work. The keyreader is just a reader, and passes the key code from the the barrel to the loom/imob. Leaving the wrong key in place with the car on Acc/Ign, you may have locked it out; it was an old story to leave it on in the hopes it would recode, but ive only heard it proven working once.
 

Snel

New Member
Ok, sweet well its a metal case and I'm pretty sure that lachies is a metal case as well. Interesting as swapping the key reader is what allowed the car to turn on, maybe the mirage one died. We did the recode trick on lachies car to get it to start after many many hours of trying to get the engine light away.
 

donki

Administrator
Forum Administrator
Ok, sweet well its a metal case and I'm pretty sure that lachies is a metal case as well. Interesting as swapping the key reader is what allowed the car to turn on, maybe the mirage one died. We did the recode trick on lachies car to get it to start after many many hours of trying to get the engine light away.
The reader itself is just a small transistor and a couple of loops of thin copper wiring to create a sort of induction loop. The copper wire is thinner than a hair, and its sounding that its now becoming fairly common for it to break now that more people are doing swaps.
 

Snel

New Member
So spoke to Lachie tonight and he says his ecu is a plastic one and ours is metal so that means it won't work right? Would we have to swap the whole loom or would we need to swap the engine as well?

Could we instead unlock the ecu to not require the immobiliser?
 

SDate42

Well-Known Member
Lifetime Premium Member
So spoke to Lachie tonight and he says his ecu is a plastic one and ours is metal so that means it won't work right? Would we have to swap the whole loom or would we need to swap the engine as well?

Could we instead unlock the ecu to not require the immobiliser?
If you have a plastic one it can be unlocked, however metal case cannot.

If it previously had an AFTERMARKET IMOB, it’s very likely the fuel pump power supply is lumped in with that. You will need to locate it and ensure it is connected to the ecu without any breaks. Alternatively run your own power supply to it via an ign switched relay. The fuel pump should always prime. Only injectors cut by imob iirc.

Further, leaving the key in the barrel for an hour with ignition on is not documented by mitsubishi anywhere that i can find. It IS however, listed by holden as a method starting a commodore with a dud key or imob unit. I think theres a bit of Chinese whispers going on, but i’m open to being wrong lol

Edit: wording
 
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donki

Administrator
Forum Administrator
I know ive had issues with trying to swap plastic case ECUs with metal case ECUs, but its not every swap - something with the pins not fully correct for the imob, aircon activate function, and the fuel pump.

No chance to use the same ecu/imob/key/barrel from the one car?
 

Snel

New Member
We will try swapping our metal case ecu imob and key with the plastic ecu imob and key from Lachie car and get back to you guys. The fuel pump doesn't prime but we tried starting the car with the fuel pump directly powered but to no avail so no injectors?
 

donki

Administrator
Forum Administrator
Why not just immob unlock a plastic case ecu and call it a day?
Maybe something related to this:

I know ive had issues with trying to swap plastic case ECUs with metal case ECUs, but its not every swap - something with the pins not fully correct for the imob, aircon activate function, and the fuel pump.
Personally i havent seen it work (swapping a plastic case in for a metal), but it may with a butchered loom
 

Doomslayer

Active Member
Maybe something related to this:



Personally i havent seen it work (swapping a plastic case in for a metal), but it may with a butchered loom
So donki. I've put all my red plastic mirage ecu and key bits into the mirage and same issue

Cel and no fuel

Would I be able to use the engine loom from the metal ecu, with my plastic ecu? Assuming I unlock the plastic ecu and delete the immob.

Or would I have to swap the entire engine loom with the newer version of the engine loom. But would that even work with the older motor?
 

donki

Administrator
Forum Administrator
So the black ecu (immob deleted) will work with the motor that originally had a metal ecu
Mostly yes. It will run with the imob disabled. IIRC, there may be some very very minor changes with the tune in regards to fueling, but we're talking the difference of like "emptying all the spare change out of the car" level of difference
 

Doomslayer

Active Member
Mostly yes. It will run with the imob disabled. IIRC, there may be some very very minor changes with the tune in regards to fueling, but we're talking the difference of like "emptying all the spare change out of the car" level of difference
so pretty much no difference. Cool

Does the key still need to match the ecu? Or now that immob is gone any key can start the car basically?

Also best to message Hens on the forum?
 

donki

Administrator
Forum Administrator
I believe the metal case used a different MAF and TPS, so its fueling calculations are worked out slightly differently on the ECU, and this could cause some issues, but if the ecu is getting the imob disabled its only 30seconds more to change the MAF tables (also im not sure if these are recorded anywhere, as the metal case was read-only, and never rewriteable. Should still be only a 30second job).

No imob means you could jam a screwdriver in the ignition barrel and turn it and it'll fire up.

@Hens on the forum, could try Hens Performance on facebook too.
 
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