'87 GN has been sitting for 6 months over the winter with a mix of 110/116 in the gas tank.
Just put on a new delco coilpack and module that tested great on a Caspers tester. New Magnicore 10mm wires and new Autolite 104s gapped at .032. I run a FAST w/ WBO2. After doing these changes I started the car up first the first time in 6 months. Took a couple times but it started fine. Let it warm up and took it around the block. Car felt like it was running on 5 cylinders. Turned it around and went home. When I pulled the car into my garage, I put it in neutral and revved it up to about 2500. It popped. I did it again and it popped again. I thought from the intake. No boost was being made. Shut it down and changed the plug wires with working old ones. Same pop. Pulled the plugs. All the plugs were light gray to a white, lean right.? The only problem is number six was clean. Like it wasn't even fired. I regapped the plugs to .035 and put them back in. I used one of the working plugs in six and put a new one in the other hole. Put the brand new Magnicores back on, because it wasn't the wires. Car sat like this for the night. Went to start it up the next day. Started fine, let it warm up and revved it up to 2500 in neutral again. No pop. Did it a couple other times and I did get a pop, from what I thought was the exhaust and it seemed to pop when I let off the gas after revving it. I looked back at the exhaust and a decent amount of black smoke was coming out, rich. So I did a record with the FAST to check. As the car was sitting in neutral at idle, my record read:
rpm 900
02 Corr 0.0
Act A/F 11.81(rich, considering I have the goal set at 13.0)
Spark 37
Inj DC 2.3
Boost -6.0
Revved it to 2050
rpm 2050
02 Corr -2.3
Act A/F 12.62 (goal is 13.0)
Spark 24.5
Inj DC 6.1
Boost -3.3
I leaned out the A/F to 13.5, no change. Revved it up to 2500 and still popped with black smoke out exhaust. Have not taken the car out since this and have not pulled the plugs again. Could it be the old gas or a bad 02. I have ran leaded fuel for the last year. Car was fine six month ago. Looking for some help first. Thanks.
Just put on a new delco coilpack and module that tested great on a Caspers tester. New Magnicore 10mm wires and new Autolite 104s gapped at .032. I run a FAST w/ WBO2. After doing these changes I started the car up first the first time in 6 months. Took a couple times but it started fine. Let it warm up and took it around the block. Car felt like it was running on 5 cylinders. Turned it around and went home. When I pulled the car into my garage, I put it in neutral and revved it up to about 2500. It popped. I did it again and it popped again. I thought from the intake. No boost was being made. Shut it down and changed the plug wires with working old ones. Same pop. Pulled the plugs. All the plugs were light gray to a white, lean right.? The only problem is number six was clean. Like it wasn't even fired. I regapped the plugs to .035 and put them back in. I used one of the working plugs in six and put a new one in the other hole. Put the brand new Magnicores back on, because it wasn't the wires. Car sat like this for the night. Went to start it up the next day. Started fine, let it warm up and revved it up to 2500 in neutral again. No pop. Did it a couple other times and I did get a pop, from what I thought was the exhaust and it seemed to pop when I let off the gas after revving it. I looked back at the exhaust and a decent amount of black smoke was coming out, rich. So I did a record with the FAST to check. As the car was sitting in neutral at idle, my record read:
rpm 900
02 Corr 0.0
Act A/F 11.81(rich, considering I have the goal set at 13.0)
Spark 37
Inj DC 2.3
Boost -6.0
Revved it to 2050
rpm 2050
02 Corr -2.3
Act A/F 12.62 (goal is 13.0)
Spark 24.5
Inj DC 6.1
Boost -3.3
I leaned out the A/F to 13.5, no change. Revved it up to 2500 and still popped with black smoke out exhaust. Have not taken the car out since this and have not pulled the plugs again. Could it be the old gas or a bad 02. I have ran leaded fuel for the last year. Car was fine six month ago. Looking for some help first. Thanks.
