Low Voltage at coil

[ladderboy 0]

Won't start. Checked fuel delivery, all good. Checked sparks. First one is good, then after that they're there, but pretty weak. Checked LT voltage at coil, only 10.5v despite 13v at battery. What could be causing the drop? Wiring looks pretty simple between coil and instrument cluster, but I can;t find wiring diag for cluster. I do have a Cobra Alarm/immobiliser fitted. Could this be causing it? Wondered if I should just pull the whole thing out..........

[Telf 224 2 Cars]

Battery is connected almost directly to the coil. I'd check the condition of your battery terminals/crimps

[jackherer 543]

As a test run a wire straight from the battery positive to the positive terminal on the coil.

 

The immobiliser is probably just spliced into the wires from the ignition barrel, it's worth checking the connections because often they are very badly installed.