I was recently driving home from work when I began to lose power intermittently. I managed to make it to about ten miles from home. I wasn’t sure what was happening, but the symptoms were suspiciously familiar. Yup, distributor. As you know, I’ve had my share of Fiero distributor issues already, to the point that I’d completely replaced it. Now what? Turns out, after much investigation, that the pickup coil was the most likely culprit. No problem! I’d bought a spare pickup coil last year, before I replaced my distributor. I’ll just throw that into— wrong! I’d replaced my old distributor with one of a better design. I’d thought that was a ‘new and improved’ design, but it turns out that it was the design that was used in ‘84, which was replaced the next year with a cheaper, flimsier design. No wonder GM went with a distributorless ignition in ‘87.
So, after figuring out that I needed an ‘84 pickup coil, I searched for a replacement, which proved not as easy to find as an ‘85/’86 unit. I found that there are two available, Expensive ($40-ish to $70-ish), and Inexpensive ($12-ish to $25-ish). I opted for Inexpensive, mainly because Inexpensive happened to also be Locally Available.
Now it was time to disassemble the distributor. Of course, one should mark the distributor and it’s relative position on the engine block before removal, as well as the distributor shaft’s relation to the body, before and after removal, so you can get everything back into position with relative ease. Also, remove the negative battery cable from the terminal, I have a remote starter and I can’t tell you how many times I’ve accidentally bumped the start button on the fob. Not cool if you have the distributor out – makes a short project a much longer project. Mark the distributor drive gear/distributor shaft relationship too, before driving out the pin that holds the gear on so you can reassemble the same way.
After pulling out the distributor and disassembling it, I found that Inexpensive also meant wrong. As you can see in the following picture, the old one is indexed with a hole in the bottom that a pin fits in, while the new one has a tab that fits in a notch in the distributor, which my distributor didn’t have. I guess it was now time to get creative…
As you can see, I disassembled the bad coil housing. Turns out, the coil inside each of the housings is identical, and they’re identical to the coil used in the ‘85/’86 distributor. You can also see why I had to replace the coil to begin with, the wires had gotten pinched when I put the distributor cap on. Lesson learned – again.
The new ‘85 coil also has an indexing nub, which is cut off the ‘84 coil, so I snipped it off.
Assembling the coil into the housing is no big trick, until it’s time to align everything. I found that I had to leave the screws of the housing loose, and use a strip of 3×5 card paper to properly space the 4 points of the housing evenly to the 4 points of the stator on the distributor shaft. I wish I had a picture of this step, but you’ll just have to imagine what I mean.
Here’s the distributor reassembled:
Now I stuck it back in the car, and reset the timing. Remember, you can’t just set the timing with a light, you have to put the computer in diagnostic mode by bridging the ALDL connector’s A and B terminals while you adjust the timing to 8 degrees BTDC.