I originally got the car from my brother, (he owed me money, and I am still on the losing end of that deal!). It had sat for several years due to a blown transmission. The following takes place over the period of three years. I am also working on remodeling the house, new kid, college at night, a Dad that insists that I work on his 87GN and his house instead of my projects! So if the following looks familiar, that's because I have posted before. But I tried what was suggested; it didn't work; so I am posting again with an update.
First thing I did was overhaul the transmission (three years ago now).
Before starting engine for first time, I did the basic tune-up stuff. New plugs, wires, fuel filter, PCV, etc., etc., etc., When I did attempt to start engine for first time after tranny rebuild, no oil pressure. Taking apart the oil pump to pack it with vasoline I found very heavy grooves worn in the plate, so I machined it flat and re-installed it. Everything ran well, I was able to drive the car, so I thought "Great! Now to work on the interior!"
As soon as I drop the seats off at the shop, the motor decides not to run anymore. So over the next couple of years I am attempting to find out what went wrong (so much for interior restoration!)
I kept getting plugs that shared a coil to foul (I later found out it was coincidence), even after replacing the coil pack, so figured it was the module itself. Upgraded the module to the 87 version (84 replacement was expensive!). I used the instructions on gnttype.org Still the same problem. Note: I first used a used GM stock unit, then I used a new Wells ignition module. Same results.
Close inspection showed many cracks in the headers, had them fixed. No Improvement.
Checked compression. Lowest cylinder was 145 lbs (checked it cold).
After lots of reading I knew that it couldn't be the crank sensor, because it sort of wanted to run, so I started looking into the cam sensor as the culprit. New cam sensor and plugs (I have gone through several sets of plugs because of the fouling problem). Still no success.
Then (this recently, about two months ago) Dad asks me "How old is that gas?" Pause from me as I think dumbly.
I then pump out about 5 gallons of very yellow varnish. Add 5 gallons of AGRI-Plus 90 (our local gas station has a pump that has a gasoline that has additives for lead replacement, detergents, stabil, anti-varnish, etc., etc., very good for older equipment or stuff that doesn't get used a lot) and new plugs, again. Now it tries to run if I feather it. Acts now like it is out of time. But I was very happy! This was an improvement over the last few years.
I still have the 233 regulator. Pressure is solid at 30lbs. No leak down, even after an hour. As another troubleshooting step, I used injectors that just came out of my Dad's 87 which was running perfectly before they were removed (he upgraded to 42.5lb). When I pumped the old gas out, I had a very solid stream.
Removing the front cover showed the worst timing chain I ever saw. Beleive it or not, but all of the nylon was intact, but with deep grooves worn in it, as well as in the crank sprocket. The chain was so bad that when I "squeezed" it in the middle, they could darn near touch!
Timing chain installation is complete, but still doesn't want to run right. I am certain that the timing chain is on right, I had my Dad and my brother double-check me. I have uploaded a saved turbo-link ECM file on my homepage at http://www.geocities.com/turbo84gn/cars/cars.html
I can get the car to run if I feather the gas at about 1400 rpm, but I get a steady backfire. If I let off the gas it will die. I have verified spark on all six. But I am pulling wet plugs out. It really sounds like it's out of time, and there seams to be excessive crank case pressure (smoke/fumes coming from breather).
I then removed the valve covers to make certain that all of the valves were opening and closing. My calibrated eyeballs tell me that all of the rockers appear to have the same amount of travel.
Maybe I am overlooking something simple? Maybe I didn't seat all of the wires all the way onto the plugs or something.
I'm ready to pull it next to the road and put a FREE sign on it!
Any suggestions and what to look at next?
Arthur Keene
turbo84gn@yahoo.com
84GN (all stock - maybe soon all scrap!)
First thing I did was overhaul the transmission (three years ago now).
Before starting engine for first time, I did the basic tune-up stuff. New plugs, wires, fuel filter, PCV, etc., etc., etc., When I did attempt to start engine for first time after tranny rebuild, no oil pressure. Taking apart the oil pump to pack it with vasoline I found very heavy grooves worn in the plate, so I machined it flat and re-installed it. Everything ran well, I was able to drive the car, so I thought "Great! Now to work on the interior!"
As soon as I drop the seats off at the shop, the motor decides not to run anymore. So over the next couple of years I am attempting to find out what went wrong (so much for interior restoration!)
I kept getting plugs that shared a coil to foul (I later found out it was coincidence), even after replacing the coil pack, so figured it was the module itself. Upgraded the module to the 87 version (84 replacement was expensive!). I used the instructions on gnttype.org Still the same problem. Note: I first used a used GM stock unit, then I used a new Wells ignition module. Same results.
Close inspection showed many cracks in the headers, had them fixed. No Improvement.
Checked compression. Lowest cylinder was 145 lbs (checked it cold).
After lots of reading I knew that it couldn't be the crank sensor, because it sort of wanted to run, so I started looking into the cam sensor as the culprit. New cam sensor and plugs (I have gone through several sets of plugs because of the fouling problem). Still no success.
Then (this recently, about two months ago) Dad asks me "How old is that gas?" Pause from me as I think dumbly.
I then pump out about 5 gallons of very yellow varnish. Add 5 gallons of AGRI-Plus 90 (our local gas station has a pump that has a gasoline that has additives for lead replacement, detergents, stabil, anti-varnish, etc., etc., very good for older equipment or stuff that doesn't get used a lot) and new plugs, again. Now it tries to run if I feather it. Acts now like it is out of time. But I was very happy! This was an improvement over the last few years.
I still have the 233 regulator. Pressure is solid at 30lbs. No leak down, even after an hour. As another troubleshooting step, I used injectors that just came out of my Dad's 87 which was running perfectly before they were removed (he upgraded to 42.5lb). When I pumped the old gas out, I had a very solid stream.
Removing the front cover showed the worst timing chain I ever saw. Beleive it or not, but all of the nylon was intact, but with deep grooves worn in it, as well as in the crank sprocket. The chain was so bad that when I "squeezed" it in the middle, they could darn near touch!
Timing chain installation is complete, but still doesn't want to run right. I am certain that the timing chain is on right, I had my Dad and my brother double-check me. I have uploaded a saved turbo-link ECM file on my homepage at http://www.geocities.com/turbo84gn/cars/cars.html
I can get the car to run if I feather the gas at about 1400 rpm, but I get a steady backfire. If I let off the gas it will die. I have verified spark on all six. But I am pulling wet plugs out. It really sounds like it's out of time, and there seams to be excessive crank case pressure (smoke/fumes coming from breather).
I then removed the valve covers to make certain that all of the valves were opening and closing. My calibrated eyeballs tell me that all of the rockers appear to have the same amount of travel.
Maybe I am overlooking something simple? Maybe I didn't seat all of the wires all the way onto the plugs or something.
I'm ready to pull it next to the road and put a FREE sign on it!
Any suggestions and what to look at next?
Arthur Keene
turbo84gn@yahoo.com
84GN (all stock - maybe soon all scrap!)
