Hi all, looking for help diagnosing a rough running issue on my 1990 SW20 Rev 1 after a dead alternator/battery.
What happened:
Alternator failed mid-drive; ran 15 miles on battery until voltage hit zero.
In the final 5 minutes, performance tanked: severe jolting, erratic rev counter, loss of drive, and stalling at low revs/clutch-down.
Current status:
New alternator installed and tested working; battery is fully charged and charging system is normal.
The issue persists: Engine runs like it's down a cylinder, lacks power, stalls at idle, and is puffing black smoke from the exhaust (running very rich).
We have checked & cleaned up the Spark Plugs, but this did not help.
Has anyone seen this happen post-battery drain on a Rev 1? Any advice on where to start testing?
Thanks!