- Distributor cleaned, pulled out and cleaned some more
- A lot of dust, rust etc under the distributor cap
- Also, there were some mysterious black flakes on the distributor shaft, but they didn't seem metallic. They don't react to a magnet, and break when you crush them with your fingernail.
- Ignition Control Module (ICM) in the distributor replaced (Standard Motor Products LX340)
- Ignition Coil replaced (Standard Motor Products DR37)
- ECM & its PROM chip replaced (original part, ordered from an eBay merchant in California, pulled from a 1992 Camaro, )
- PROM version is "AXKT", while the original was ANTT. As far as I know, AXKT is just a compatible upgrade.
- Battery negative terminal connector replaced
- The threads attaching the cables to the old connector were gone, so this might have caused some contact issues
- Grounding cable between battery and chassis replaced, contact point in chassis cleaned
- Grounding cable between battery and engine block was left in place, looks "ok"
- Battery terminals and connectors cleaned
- Wires to the Heater / AC blower motor disconnected
- Wires to the AC compressor disconnected
- I don't know what condition the AC is in, at best it's very low on refridgerant
I had hoped that blindly replacing most of the ignition-related parts would take care of this problem, but the same symptoms that I had last fall are still there. I think things got a bit more reliable after I fixed the battery contacts and disconnected the heater/AC blower motor, so bad grounding and that worn-out motor were probably at least part of the problem. Still, this only lowered the frequency at which the symptoms occur.
I made a test drive of about 9 km today (5.5 miles), and the car died / SES'd maybe half a dozen times.
Next up, I'm looking at
- Replacing the distributor Pick-up Coil (since I already have a new spare part)
- Replacing vacuum hoses
- Replacing the whole distributor (at about the same cost as all those distributor parts above....)
- Replacing the grounding cable between battery and engine block
- Checking / replacing the cable for the VSS (Vehicle Speed Sensor)
- Replacing that 8th plug...
- Checking the fuel pump wiring
- Replacing the TBI injectors
If none of this helps, it looks like I'll have to switch my brain on, do a bit of homework and actually try to diagnose the problem in a structured way.