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will non EPROM ecu work in 92 EPROM vr4?

presterone

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Found lots of info from people who are switching to EPROM for obvious reasons, I am just trying to get the car on the road and there is a non EPROM ecu close by for sale. Its from a 92 fwd turbo laser anyone know if it will work?
 

89Mirageman

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As long as the laser had a M/T it will work. It'll actually still work if its from an auto but it won't run 100% since its meant to run 390cc injectors.
 

tektic

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The Galant boost gauge won't work. The timing maps are slightly different on a fwd. The idle will be lower. If its 94 or California ecu it will want to see egrt sensor.

Regardless it will run the car.
 

jepherz

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Quoting tektic:
The Galant boost gauge won't work. The timing maps are slightly different on a fwd. The idle will be lower. If its 94 or California ecu it will want to see egrt sensor.

Regardless it will run the car.



You sure about the boost gauge?
 

thomcasey

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My son is running a 91 non-eprom T/E/L ecu in his 91 VR4 and the boost lights work.
 
Last edited:

tektic

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Sorry, I didn't mean not work. The code values are very different. Don't expect it to be accurate.
edit: not that they are accurate to begin with.
 
Last edited:

DR1665

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I bought 195/2000 with a non-EPROM ECU from a 92 auto DSM. Didn't see any difference in drivability after swapping.
 

Wizardawd

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FWD/AWD there is no real difference in any mapping.

MT/AT, supposedly there is a little difference in the fuel mapping, but remember MT/450cc/37psi, AT/390cc/43psi. Probably incredibly similar.

But in my experience, I have yet to see any difference in ANY 1g Turbo ECU (90 is the exception, until the wires are swapped) in any DSM/GVR4 as far as driveability and even power.

By the time any difference would be an issue, you are probably running link or piggybacks anyways which makes it all irrelevant.

I have a 92 AWD MT with a 91 ECU, a 91 GVR4 with a 92 MT FWD Link Ecu, 91 GVR4 with another 91 AT FWD ecu.

Wiz
 

presterone

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Hah I posted in the other ecu thread I started. Such a noob anyway I got the car running with a non EPROM 91 gvr4 ecu. Won't idle sputters a bit at low rpm and boost gauge fluctuates when I rev it up from a standstill. Hey at least it runs.
 

tektic

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there is a bin number on every chip. If two chips have different bin numbers the code contained on the two chips is not identical. I can show line for line map for map how they're different, but this guy on tooners did that already. He's talking only about dsm chips too. A Galant vr4 even has different number in the maf comp table than a 1g dsm.

Will a dsm ecu fire the engine and run the car? Yes. Even a non turbo ecu will run a turbo car. Is it possible it could lean out unexpectedly? Possibly, Yes.

If you only need the car to run, almost any ecu that has the same plug (even a 90 dsm which is wired differently) will make the car run, but I assure you it's not the same unless the ecu part numbers or bin numbers mach.

Heres the thread

Quote:

I have a 92 AWD MT with a 91 ECU, a 91 GVR4 with a 92 MT FWD Link Ecu, 91 GVR4 with another 91 AT FWD ecu.



-91 and 92 dsm ecus part numbers are the same.
-the ecu used with link is irrelevant because it replaces all of the operating software.
-at fwd ecu is different.
 
Last edited:

Wizardawd

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My point is, any TURBO ECU has run my cars and countless others just fine. Regardless of driveline type, transmission type and GVR4/DSM, etc. Is there a difference in the coding...yes. Anything that anyone should honestly give a sh*t about other than high HP cars....no. And the high HP cars are, as you said, running link or some other software that makes the source coding irrelevant.

Main problem with the NT boards is the lack of the knock sensor circuit and the fact they are for 240cc injectors. I've seen guys run them for years in Turbo cars as long as they stayed out of boost.

And ALL turbo ecus lean out unexpectedly....it was called fuel cut.

And not quite the same part numbers on the ECUs:

click

Wiz
 

tektic

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Yeah your right. There all the same. I don't know what I was thinking. Considering driveability when I put my car back together? I must be crazy! Who cares if the fuel injectors are different sizes? So what's the differentce if it sputters and stalls or has no pickup or dead spots in accelerating? Its still going to make that cool wooshing sound when the turbo kicks in yo. The turbo may glow red hot when I'm done boosting because the map is too lean throughout. that's fine by me. As long as I don't hit fuel cut. Tell everyone who asks from now on that ecus are magical and they know what they need to do to run the motor no matter what parts are conected to it . Just as long as noobs understand this... I can't think of better advice to give about engine management. Oh. Unplug your bov too while your at it.
 

Wizardawd

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Find a single issue when running a properly functioning turbo ecu regardless of the part number. And I do mean an issue directly related to the coding of the ecu not any other issue like a bad sensor.

There has never been one, lots of research and nothing turned up other than the code is different but it makes next to no difference anyways. Todd and Tom both did research back in the day and never found anything relevant. And remember, I'm talking TURBO ecu's.

Wiz
 

89Mirageman

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Makes sense, I ran an auto ecu in my 92 auto talon and swapped over to 14b/450s and it ran great. I didn't even bother switching out the fpr although I probably should have.
 

presterone

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It was from a 91 gvr4. And it very well could be something else wrong with the car but I wanted to look into it in case I had to swap pins or something.
 

Wizardawd

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If it was the original ECU, it should be an EPROM already. But, more than likely, due to the high failure rate of these ECUs it was swapped out at some point. Follow the link above and match it to the board number after you open the case to find out exactly what it's from. Usually, look at the 3 capacitors on the board for leaking and damaged components due to the leaking caps. Also, a fishy smell is sometimes present also.

As for symptoms of a failing ECU:

No start
No spark/fuel
No power to cam sensor
No power to EFI relay next to ECU
Boost gauge does not light up when keyed on
Rapid clicking from EFI relay after car has started
Tach needle jumping erractically while running (corresponds with the clicking of the relay)

Wiz
 

presterone

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brunswick maine
Thanks. Yea the 91 ecu I tried runs the car but doesn't idle and no CEL with key on. The board looks fine and it was rebuilt by ZDR electronics.
 

tektic

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ronkonkoma, ny
Quoting Wizardawd:
Todd and Tom both did research back in the day and never found anything relevant.
Quote:


I'd love to see a reference.
 
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