I have been working to get my '84 running properly so I can start driving it as a daily. On my first 50 mile trip, the CEL came on intermittently. I also noticed that the exhaust smelled rich. So, I used the paperclip scanner an came up with 2 codes. First was code 42 - Electronic Spark; and second, was code 45 - Rich Exhaust. First, I inspected the spark plug wires. I found the number 1 spark plug wire was loose and not making a solid connection Next was the Rich Exhaust. I'm not a mechanic. I had to look up the causes of Rich Exhaust. The most common cause I found was a bad Coolant Temperature Sensor. So I replaced it. Little did I know, the sensor connection had changed at some point. So I had to splice in a new connector to match the new sensor. Following the replacement, I cleared the codes and went for a short drive. After getting home, I checked the codes again. 12s across the board. Raise the roof here folks! Now, I'm on to the next issue. It seems to have a miss. This is where I ask the wonderful folks here on PFF for help. I don't have any codes. What could be causing this? The symptoms are: almost stall after high rev. Hesitation when stepping on gas. Sounds like it has a miss when maintaining 2k to 3k rpms.
Ahh. It wouldn't have been necessary for the sensor going to the gauge or the fan. However, at some point, GM decided to change the ECM sensor from a "nipple" style connector to one similar to the rest of the connectors. I think I may have an earlier production run. I wish I could post pictures here. But, I don't have a PC to download the forum's picture tool.