View Full Version : Help. Inconsistant spark

08-16-2011, 03:42 PM
I am having a problem where the boat is ideling real poorly and has a hard time starting. Boat seems to run pretty well over 1000rpm.

I put a timing light on to check the base timing and noticed that the spark was very inconsistant. The timing light would flash but not at a constant rate. Making me think that the spark would occur only 50% of the time or so. For a while I suspected the timing light but was able to prove it is OK. Reving the engine up to 1000rpm seems to make the spark more constant and the engine starts to run beter.

Had a look at the distributor cap and found some corrosion on the inside terminals. Cleaned that off but the boat runs the same.

I have noticed that the spark is much more inconsistant when the computer is in the "diagnostic" mode that you put it into so that you can time the engine. In diagnostic mode the engine will barely run.

Any ideas?