92 LT-1 ECM Issues
Thread Starter
Racer
Joined: Dec 2013
Posts: 419
Likes: 5
From: Bel Air Maryland
92 LT-1 ECM Issues
Earlier this year, I had some performance upgrades made to my 92 LT-1. My tech told me there would be some limitations because of potential tuning problems associated with the ECM used in my car. For example, he explained that the chip used in the ECM is not programmable so it's not possible to tune the motor using a laptop. Instead, he sent the ECM to Ed Wright who "burned" and installed a new chip based on all of the engine specs we gave him. Now, I'm looking into making some additional performance upgrades but have concerns about what can and/or cannot be done because of the limitations posed by the ECM in the 92 LT-1. I contacted Lloyd Elliott who suggested possibly converting over to an OBD-I or OBD-II, but didn't offer any other details. So, can anyone tell me whether such conversion is possible and, if so, what would be involved in doing it?
Thanks ........... WS
Thanks ........... WS
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Your ECM has an EPROM (Erasable Programmable Read Only Memory) IC (Integrated Circuit) that contains the program that runs the car. Note the "erasable". The trick is that you need to take the EPROM out of the ECM and then use an ultraviolet light to do the erasing. After the old program has been erased, it can be programmed using a programmer box with whatever program you need to work with your modifications.
Later C4s have an EEPROM (Electrically Erasable Programmable Read Only Memory). They can be erased by sending a magic code through the ALDL port and then reprogrammed, also through the ALDL port.
Your car is OBD I. 1996 and newer cars are OBD II. That refers to how the ALDL port is used to access the ECM (and other modules if your car has them).
Later C4s have an EEPROM (Electrically Erasable Programmable Read Only Memory). They can be erased by sending a magic code through the ALDL port and then reprogrammed, also through the ALDL port.
Your car is OBD I. 1996 and newer cars are OBD II. That refers to how the ALDL port is used to access the ECM (and other modules if your car has them).
Last edited by Cliff Harris; Oct 5, 2014 at 03:25 AM.
Drifting
Joined: Oct 2004
Posts: 1,477
Likes: 80
From: Hawaii
Upgrade your ECM with a Moates Ostrich. Enables you real time programming.
https://www.moates.net/ostrich-20-th....html?cPath=64
https://www.moates.net/ostrich-20-th....html?cPath=64
Safety Car
Joined: Jun 2003
Posts: 4,250
Likes: 656
From: San Diego Ca
Or do the simple thing and buy TunerCat and a chip burner along with a chip eraser.
Will cost a few hundred but if you want to work on the car you need to go there. Might as well get a copy of DataMaster so you can log things.
I love Craig Moates, but starting with something that can real time program seems like a recipe for disaster for a neophyte tuner.
I do have the Moates RRer for my 98, so know the advantages just don't like that idea for a newbie to tuning.
Will cost a few hundred but if you want to work on the car you need to go there. Might as well get a copy of DataMaster so you can log things.
I love Craig Moates, but starting with something that can real time program seems like a recipe for disaster for a neophyte tuner.
I do have the Moates RRer for my 98, so know the advantages just don't like that idea for a newbie to tuning.
Thread Starter
Racer
Joined: Dec 2013
Posts: 419
Likes: 5
From: Bel Air Maryland
Your ECM has an EPROM (Erasable Programmable Read Only Memory) IC (Integrated Circuit) that contains the program that runs the car. Note the "erasable". The trick is that you need to take the EPROM out of the ECM and then use an ultraviolet light to do the erasing. After the old program has been erased, it can be programmed using a programmer box with whatever program you need to work with your modifications.
Later C4s have an EEPROM (Electrically Erasable Programmable Read Only Memory). They can be erased by sending a magic code through the ALDL port and then reprogrammed, also through the ALDL port.
Your car is OBD I. 1996 and newer cars are OBD II. That refers to how the ALDL port is used to access the ECM (and other modules if your car has them).
Later C4s have an EEPROM (Electrically Erasable Programmable Read Only Memory). They can be erased by sending a magic code through the ALDL port and then reprogrammed, also through the ALDL port.
Your car is OBD I. 1996 and newer cars are OBD II. That refers to how the ALDL port is used to access the ECM (and other modules if your car has them).
Thanks ......... WS
Safety Car
Joined: Jun 2003
Posts: 4,250
Likes: 656
From: San Diego Ca
The 92/93 both use the inserted chip in the ECM. $DA2 is the Def file for both years. $DA3 is for the 93 F body. The PCM for both is the same part number only the chip is different.
The older OBD1 tuning systems certainly do not control as much or as many different parameters nor do they have the prolification of sensors that came with OBD2.
Don't sell them short however. They can actually be easier to tune with a big cam as you don't have so many Nannies to tune out.
What horsepower levels and are you going NA or boost?
The older OBD1 tuning systems certainly do not control as much or as many different parameters nor do they have the prolification of sensors that came with OBD2.
Don't sell them short however. They can actually be easier to tune with a big cam as you don't have so many Nannies to tune out.
What horsepower levels and are you going NA or boost?
Safety Car
Joined: Sep 2001
Posts: 4,157
Likes: 554
From: Glenbeulah Wi
The 92/93 both use the inserted chip in the ECM. $DA2 is the Def file for both years. $DA3 is for the 93 F body. The PCM for both is the same part number only the chip is different.
The older OBD1 tuning systems certainly do not control as much or as many different parameters nor do they have the prolification of sensors that came with OBD2.
Don't sell them short however. They can actually be easier to tune with a big cam as you don't have so many Nannies to tune out.
What horsepower levels and are you going NA or boost?
The older OBD1 tuning systems certainly do not control as much or as many different parameters nor do they have the prolification of sensors that came with OBD2.
Don't sell them short however. They can actually be easier to tune with a big cam as you don't have so many Nannies to tune out.
What horsepower levels and are you going NA or boost?
The 1992 computer can be tuned to run well with large cams, it just takes time and knowledge. To speed the process you can use an emulator and tune on the fly with a laptop.
