What causes weak spark from coil?
If the spark is still weak after replacing the whole ignition system, then the normal size wiring or connector to the coil may be corroded or damaged somehow. The other real longshot is that the grounding strap between the engine/trans, body, and negative battery terminal is corroded/worn/damaged.
Will an engine run with weak spark?
An engine is considered to misfire when there is not enough electrical energy going to the spark plug to keep it arcing or there is a path- way in the engine for the energy to take that bypasses the plug’s electrodes. The engine will be weak, the unburned fuel will foul the spark plug, and the exhaust will pop.
Why is my coil not producing a spark?
This wire will eliminate the possibility of a safety switch or a bare wire preventing your coil from producing a spark. If your coil produces a spark with this wire unplugged, then our problem is somewhere else. What are you using to test your spark?
What causes a no spark condition open loop?
If after unplugging the 4-plug connector there is no spark or the spark still looks weak, this tells you that the problem is in the major ignition components like the stator, coils, cdi, spark plugs, spark plug wires, possibly a short in the wiring harness, a bad trigger coil or on EFI models your Injector Coils are bad (they measure 19-20ohms).
What are the issues with a no spark motor?
Other issues related to a no spark/Weak Spark/Wet Plugs issue: Wrong flywheel on it. Sled was only running on one cylinder. Low side coil on his stator read 360 ohms and it should have measured 450 ohms. The low side coil was bad. It kept fouling plugs left and right. The guy before ran ethanol, and never told the current owner.
Why does the spark plug arc when the engine is idle?
This is due to the throttle being almost closed, the engine rpm being low, and the fact that there is no load on the engine. If the engine was still idled and a load was gently applied (engaging a PTO, for example), the voltage required to arc the plug would increase dramatically.