This is a problem that I have been fighting since last summer. I apologize if this gets a bit long winded but I figure that I may as well set out everything I have found and done right off the bat. I got the car about 18 months ago and I was extremely new to the turbo buicks. Wanted one for years and finally found the right deal at the right time)
It is an 87 GN with:
60# Injectors
TT 5.6 Chip
RJC Intercooler. (Large one that required eliminating the A/C)
Turbonetics turbo. (I called Turbonetics and he told me that was a "Stage 2.5")
Hot wired fuel pump running 42 psi
4" Down pipe and flowmaster exhaust with no cat.
Alky
LS1 MAF with a Gen2 translator (Added after the problem started)
Previous owner claimed an upgraded torque converter but was unsure of the specifics. (He bough the car himself as it was when I got it)
When I got it I could light the tires at will and it would kick you butt back in the seat. (quick spool to 22 psi of boost)
(This is where my problems started due to a brain fart on my end)
I installed a new stereo amp and simply forgot to secure the fuse. I left the house and the car laid about 100 feet of rubber and ran great.
About 4 miles later in some stop and go traffic, the car started sputtering and stalling. (stall and restart on it's own is the best way I can describe it. It was that quick)
I pulled into a parking lot and popped the hood and immediately saw the amp fuse block had hit the down pipe and shorted.
I pulled it away, secured it and all seemed fine.
As soon as I pulled away I noticed that the car sounded different. (way less turbo noise at part throttle)
I layed the throttle down and the car struggled to hit 5 psi of boost.
I posted on here and found that the wastegate actuator was pooched. (not necessarily the cause of my issue but still n/g)
I replaced the wastegate actuator and got the boost back up to 22 psi but it was still slow to hit it with little low end punch. (wouldnt break the tires loose till about 60 feet out) To reach this boost the wastegate actuator has to be pulled about 1/2" or a bit more to attach to the wastegate rod.
I tried to find someone locally who had experience on these cars and ummm yeah lol. When everyone at the GM dealership and elsewhere replied with "A Buick what??" I kinda knew I was on my own lol.
My brother works at a dealership in Winnipeg and was able to blow the dust off of and borrow their tech1 scanner.
He found that the MAF sensor was giving goofy readings.
We replaced the MAF with a donor from another GN and while it ran a bit better, the slow spool was still there.
I picked up an LS1 MAF and ordered a Gen2 translator from Eric and installed it.
We went through the car and found the gasket between the up pipe and the turbo leaking.
Replaced the gasket and it burnt through pretty much right away again because the up pipe was badly pitted.
Installed new headers and cross pipe and all exhaust leaks appear to be gone but slow spool is still there.
I just finished doing my spring cleaning today (followed the suggestions on gnttype)
All fluids looked really good.
There was very little black dust in the tranny pan and the fluid was red and smelled good.
Took it out and tried to brake load it and I can build no boost before the tires break loose (at about 23-2600 rpm)
O2 at idle is around 775, pushing recall on the scanmaster after a run it read 834 and no knock retard.
There is my novel for now lol. If I forgot anything I will post it but I believe that is everything.
It is an 87 GN with:
60# Injectors
TT 5.6 Chip
RJC Intercooler. (Large one that required eliminating the A/C)
Turbonetics turbo. (I called Turbonetics and he told me that was a "Stage 2.5")
Hot wired fuel pump running 42 psi
4" Down pipe and flowmaster exhaust with no cat.
Alky
LS1 MAF with a Gen2 translator (Added after the problem started)
Previous owner claimed an upgraded torque converter but was unsure of the specifics. (He bough the car himself as it was when I got it)
When I got it I could light the tires at will and it would kick you butt back in the seat. (quick spool to 22 psi of boost)
(This is where my problems started due to a brain fart on my end)
I installed a new stereo amp and simply forgot to secure the fuse. I left the house and the car laid about 100 feet of rubber and ran great.
About 4 miles later in some stop and go traffic, the car started sputtering and stalling. (stall and restart on it's own is the best way I can describe it. It was that quick)
I pulled into a parking lot and popped the hood and immediately saw the amp fuse block had hit the down pipe and shorted.
I pulled it away, secured it and all seemed fine.
As soon as I pulled away I noticed that the car sounded different. (way less turbo noise at part throttle)
I layed the throttle down and the car struggled to hit 5 psi of boost.
I posted on here and found that the wastegate actuator was pooched. (not necessarily the cause of my issue but still n/g)
I replaced the wastegate actuator and got the boost back up to 22 psi but it was still slow to hit it with little low end punch. (wouldnt break the tires loose till about 60 feet out) To reach this boost the wastegate actuator has to be pulled about 1/2" or a bit more to attach to the wastegate rod.
I tried to find someone locally who had experience on these cars and ummm yeah lol. When everyone at the GM dealership and elsewhere replied with "A Buick what??" I kinda knew I was on my own lol.
My brother works at a dealership in Winnipeg and was able to blow the dust off of and borrow their tech1 scanner.
He found that the MAF sensor was giving goofy readings.
We replaced the MAF with a donor from another GN and while it ran a bit better, the slow spool was still there.
I picked up an LS1 MAF and ordered a Gen2 translator from Eric and installed it.
We went through the car and found the gasket between the up pipe and the turbo leaking.
Replaced the gasket and it burnt through pretty much right away again because the up pipe was badly pitted.
Installed new headers and cross pipe and all exhaust leaks appear to be gone but slow spool is still there.
I just finished doing my spring cleaning today (followed the suggestions on gnttype)
All fluids looked really good.
There was very little black dust in the tranny pan and the fluid was red and smelled good.
Took it out and tried to brake load it and I can build no boost before the tires break loose (at about 23-2600 rpm)
O2 at idle is around 775, pushing recall on the scanmaster after a run it read 834 and no knock retard.
There is my novel for now lol. If I forgot anything I will post it but I believe that is everything.
