Crank no spark
Completely stumped here. I have tried my speeduino, the stock ecu, 2 coil packs and a set of COPS. I cant get a spark at all. I've checked the wiring and they have power and ground. Sadly I don't have an oscilloscope to check for the signal being sent to the coils. Any thoughts as to why? car is a mk2.5 1.6 EDIT: i have attached a datalog aswell
Last edited by HatedByThePublic; Dec 12, 2025 at 10:33 AM. Reason: Datalog
I saw that as well, looked like 8-9v while cranking, with a low of 6.5 on initial in-rush. The coils will work fine at that voltage, it's whether or not the speeduino will continue to function. Google says it's good to 8-9, but looks like your resting voltage in mid 11s, definitely not great. Put a trickle charger on it for ~12 hours and see if it helps, I have my doubts but the battery needs it regardless.
I saw that as well, looked like 8-9v while cranking, with a low of 6.5 on initial in-rush. The coils will work fine at that voltage, it's whether or not the speeduino will continue to function. Google says it's good to 8-9, but looks like your resting voltage in mid 11s, definitely not great. Put a trickle charger on it for ~12 hours and see if it helps, I have my doubts but the battery needs it regardless.
I saw that as well, looked like 8-9v while cranking, with a low of 6.5 on initial in-rush. The coils will work fine at that voltage, it's whether or not the speeduino will continue to function. Google says it's good to 8-9, but looks like your resting voltage in mid 11s, definitely not great. Put a trickle charger on it for ~12 hours and see if it helps, I have my doubts but the battery needs it regardless.
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