bobxyz
Board Member
- Joined
- Aug 29, 2014
- Location
- Boulder CO
Great!Okay, making progress.
I'd unplug the injectors, to keep from filling up the cyls, and keep spinning it by hand until you have working spark.
First off, unplug the center lead from the disti and fix it next to a shock tower bolt, or something easy to see, then spin by hand. Cleanflametrap has a nice picture showing a magnet and one of the single-wire valve cover plug wire holders setup for spark testing.
If you have spark, then the problem is between the end of the coil wire and the plugs. If not, you could try measuring the voltage between pin #1 of the coil and Battery + post while spinning by hand. This will be +0volts most of the time, but should briefly blip up when the coil is charging during the dwell time. Dwell time is roughly 0.01 seconds, so it's hard to see the blip with a meter.
If you don't see the meter twitch, you can try the same thing with the EZK to powerstage signal if you can probe it when connected. You want to probe powerstage pin #5. The EZK to powerstage wire, for a '87 740, is green (sorry, I misread GR as OR initially) but I don't know what it is in your harness. [Edit: probe this one to the battery - post, the EZK signal is 0v and pulses to +5v during coil charging.]
For the fuel pumps, they draw a pretty high current so you want them powered through a relay, instead of drawing all the power through the ignition switch. The harness that you have includes the relay, you just need to run the fat yel/red wire to fuel pump fuse(s), assuming that they're present and wired to the pumps.
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