08-17-04, 01:58 AM
Hi, Iím a new member of this forum. Iím about to purchase a 1995 Eldorado, and this site has proven extremely useful in terms of what to look for and especially in the area of care and feeding of a Caddy. One thing I discovered was that the Norstars have a governor on them, set, apparently, for different tire options available (S, H, V, Z, etc.). Since these speed settings are changed by imputing the relevant code into the carís computer, I was wondering if one does this only through a dealer, or can any reasonably up-to-date mechanic handle the alteration. Iím talking about an OBD I car here; I understand that the OBD IIís are a different proposition entirely. Any information would be much appreciated.
08-17-04, 09:59 AM
You will not get any dealer or reputable garage to change the speed settings, if they did they would be eaten alive by any lawyer/insurace group and would held liaible for any accident or problems that come up or happen after the change.
You need to check into an aftermarket chip to replace your PCM.
08-17-04, 10:03 AM
Welcome to the forum.
I am under the impression that in order to remove the speed limiter, you would need to change the pcm chip (under dash, passenger side). I have heard of people changing the chip for this reason. Some say this is the best, and maybe the only only, benefit of changing the chip.
08-17-04, 02:56 PM
Would that be something like the SuperChip?
08-17-04, 04:13 PM
Yes, Superchips makes on for the 93-95 Northstars. I had one in my 94 Concours, it removed the speed limiter, and added aroun 14 HP and 28 lbs-ft of torque.
08-17-04, 06:07 PM
That sounds terrific. Did it have any unlooked for or harmful effects (or have you heard of any) on the Cad? Just trying to determine how reliable these chips are.
08-17-04, 11:43 PM
I believe the 95 Eldorado was pre OBD I. I am pretty sure that OBD I started in 96 for N* equipped Cadillacs. If this is the case then you should be able to replace the Prom Chip with one like described above that would remove the governor. If I'm wrong and yours is OBD I then it would have to be reflashed. I know even on the OBD II Eldorado ETC that if the car did not come with the Z-rated tire option and came with a governor, that if you replace the tires with Z-rated ones you can bring it to your local Cadillac dealership and they will reflash the computer to disable the top-speed limiter. From what I've heard though they can't do it if it is an ESC because they never came with a Z-rated tire option so the computer in them is permanently set to be speed limited. This is the problem I have since I have a 2000 ESC. So I would think that if yours is OBD I and it had an option for Z-rated tires from the factory with no governor, even if yours didn't come equipped with it. Then you should be able to have it reflashed by your local dealership provided you have replaced the tires with Z-Rated ones.
OBDI was pre '96. OBDII is '96 to present.
08-18-04, 03:40 PM
From a programmer point of view I dont believe that GM went trough all the trouble of writing code to disable the update of ESC and enable it on ETC. Its probably just dealer politic not to upgrade the ECU on an ESC. Essentialy the ECU in both car is probably the same, the only difference is the fuel map data and other model specific data, not update disabling code.
Just my little geeky point of view ;)