jburnsinnj
Member
- Joined
- Jan 4, 2006
Why did GM do a recall on the original factory chip on the 87' GN's I ignored the notice and still run the factory chip but am curious exactly what the difference is in the GM recall chip.
Original 87' GN Factory Chip recall
- Thread starter jburnsinnj
- Start date
H
Heisenberg
Guest
Thank you Dave
Total Dumby re: these cars. Bought 87 T late last summer. It was running rough but premium gas and injector cleaner settled it down somewhat. Was still idling rough when put away for the winter.
How do I determine what chip it has? What is involved in changing the chip?
Please pardon my ignorance, at 62 I should know about this stuff but I don't. I spent most of my life working to support a family while dreaming about these Buicks. Now the family is gone and I've got one. Now I just need an education!
How do I determine what chip it has? What is involved in changing the chip?
Please pardon my ignorance, at 62 I should know about this stuff but I don't. I spent most of my life working to support a family while dreaming about these Buicks. Now the family is gone and I've got one. Now I just need an education!
Just remember one thing; the chip does not make the car run badly - unless - the ECM isn't reading the chip. So, a car that runs normally, then starts to act up, doesn't have the chip to blame. Look elsewhere.
About 80% of the problems with our turbo cars boil down to ignition related issues. And of that, maybe 75% of those problems can be traced to wiring issues. Bad electrical connectors and connections, plug wires that fail, low voltage issues related to aging wiring, etc.
First thing you need to do is remove the Fan Delay Relay. This horrible-design part is the source of many electrical issues. I have seen the relay fail and kill batteries overnight MANY times, resulting in the car owner replacing the battery, alternator, cables, etc., just to find that those weren't the culprit. You don't need it. Remove it. Period.
The rest of your problems are usually sensor failures or calibration drifting, such as a defective MAF sensor or polluted oxygen sensor. The stickler is the MAF; it can go out of calibration and NOT set a code. Usually results in excessive rich condition, or bad idle. A scan tool is a must. And a box of spare parts is also a great thing to have. Scour the earth to find an original Delco coil module and MAF sensor, it'll buy you years of normal running operation.
And finally, weld the crack on the header near the No. 3 exhaust port. It's there. You have it. Fix it. That crack is the major source of rich-running engines as is sucks air during idle and fools the O2 sensor into thinking the engine is lean.
Print this post, read it before you go to bed at night, and memorize it.
About 80% of the problems with our turbo cars boil down to ignition related issues. And of that, maybe 75% of those problems can be traced to wiring issues. Bad electrical connectors and connections, plug wires that fail, low voltage issues related to aging wiring, etc.
First thing you need to do is remove the Fan Delay Relay. This horrible-design part is the source of many electrical issues. I have seen the relay fail and kill batteries overnight MANY times, resulting in the car owner replacing the battery, alternator, cables, etc., just to find that those weren't the culprit. You don't need it. Remove it. Period.
The rest of your problems are usually sensor failures or calibration drifting, such as a defective MAF sensor or polluted oxygen sensor. The stickler is the MAF; it can go out of calibration and NOT set a code. Usually results in excessive rich condition, or bad idle. A scan tool is a must. And a box of spare parts is also a great thing to have. Scour the earth to find an original Delco coil module and MAF sensor, it'll buy you years of normal running operation.
And finally, weld the crack on the header near the No. 3 exhaust port. It's there. You have it. Fix it. That crack is the major source of rich-running engines as is sucks air during idle and fools the O2 sensor into thinking the engine is lean.
Print this post, read it before you go to bed at night, and memorize it.
I bought a GN brand new in 1987 and never got a notice for the chip recall ?? I had the car for 2 years, but i am a Canadian maybe we never got the recall notice. On another note for the fan delay relay, just remove it , period. nothing else to wire up or replace? All this does is turn on the fan to cool it after the car is shut down ?
Thanks, I'll look into that as soon as the weather gets up near freezing!
dartguy340
T-Type guy
- Joined
- Oct 2, 2010
Me too, it's too snowy and cold here right now! 
GNONYX
Well-Known Member
- Joined
- Oct 16, 2009
Ya, I run that chip in my 87, and love it!!!!
Back to the OP, I have a theory of why that recall chip was offered in the first place.
In 86, the GN with it's intercooler took the enthusiasts by storm, kind of blind-sided the public. By 87, the performance industry embraced the car well, and several performance products were starting to surface, albeit very pricey.
The first pioneers of performance chips loaded the pages of Hot Rod magazine with very pricey plug-and-play chips. You needed to lay down $200-plus to go that route. And mostly, they did nothing more than increase the boost and -maybe- tweak the timing and fuel a bit. Pricey as they were, there were companies who cloned those chips, "Chips R Us" comes to mind, which made a quick plug-and-go performance product an affordable alternative. For $200, you got ten clones in a neat little box. And as a matter of priority, one of the first things you did after replacing the chip was to "crush" the fuel pressure regulator, forcing it into higher base fuel pressure, which you needed when you slammed those injectors near the 100% duty cycle mark. I believe MANY GN/Ttype owners jumped into that scene by 1988, and because turbo vehicle production was at its height, the numbers of modified GN's increased exponentially.
Two to four years into sales, many states required emissions testing. The emissions data is collected and sent to the federal level for processing. Lo and behold, somehow, these 87 turbo cars seemed to push over the top on emissions. So, what does the government do? It directs the car maker to recall those stink-bombs and fix the problem. This, I believe, layed the groundwork to the 1992 recall campaign. Why only the 87, not the 86? Why not the GNX? Numbers, numbers.
The new "BBKJ" program was basically a means to reduce emissions and satisfy the feds. One of the things GM engineers did was to widen the BLM minimums and maximums (which supports my belief that the raised fuel pressure - via fuel regulator crush) helped manage the fuel. My best guess is that the engineers at GM couldn't undo the mods, and didn't want to face the music if some nit-wit in the government felt they should remove and replace polluting engines. In the process, they gave us chip hackers some more good stuff to implement into our hacking efforts. And hacking, there was, back in those days.
Anyway, that's my rub on it. I'm sure there are a few ex-employees and retirees of GM on these forums who can add to the mystique here.
In 86, the GN with it's intercooler took the enthusiasts by storm, kind of blind-sided the public. By 87, the performance industry embraced the car well, and several performance products were starting to surface, albeit very pricey.
The first pioneers of performance chips loaded the pages of Hot Rod magazine with very pricey plug-and-play chips. You needed to lay down $200-plus to go that route. And mostly, they did nothing more than increase the boost and -maybe- tweak the timing and fuel a bit. Pricey as they were, there were companies who cloned those chips, "Chips R Us" comes to mind, which made a quick plug-and-go performance product an affordable alternative. For $200, you got ten clones in a neat little box. And as a matter of priority, one of the first things you did after replacing the chip was to "crush" the fuel pressure regulator, forcing it into higher base fuel pressure, which you needed when you slammed those injectors near the 100% duty cycle mark. I believe MANY GN/Ttype owners jumped into that scene by 1988, and because turbo vehicle production was at its height, the numbers of modified GN's increased exponentially.
Two to four years into sales, many states required emissions testing. The emissions data is collected and sent to the federal level for processing. Lo and behold, somehow, these 87 turbo cars seemed to push over the top on emissions. So, what does the government do? It directs the car maker to recall those stink-bombs and fix the problem. This, I believe, layed the groundwork to the 1992 recall campaign. Why only the 87, not the 86? Why not the GNX? Numbers, numbers.
The new "BBKJ" program was basically a means to reduce emissions and satisfy the feds. One of the things GM engineers did was to widen the BLM minimums and maximums (which supports my belief that the raised fuel pressure - via fuel regulator crush) helped manage the fuel. My best guess is that the engineers at GM couldn't undo the mods, and didn't want to face the music if some nit-wit in the government felt they should remove and replace polluting engines. In the process, they gave us chip hackers some more good stuff to implement into our hacking efforts. And hacking, there was, back in those days.
Anyway, that's my rub on it. I'm sure there are a few ex-employees and retirees of GM on these forums who can add to the mystique here.
