So today my car started running on 3 cyl. I managed to limp it home and pulled the coils. One is melted and was smoking when it came out and the other 3 were showing signs of overheating and they had black soot on the electrode/spring.
When I was running my Megasquirt last year, I ran these coils for 15,000kms on a 3ms Dwell cycle as per the reasons given by Joe Perez. The MS has options for cranking and running dwell. Cranking on the MS was 3.2ms or so.
On ECU Manager I only had the option for one dwell setting so I chose 3ms to be safe. I presumed the voltage calibration was the same as the MS, but obviously I was wrong. I am running a Haltech Spring ECU btw.
Here is a photo of the coil that stopped working, and one of the other three that were black and hot... but still working.
One of the others that still worked... but was black. 15,000kms with the MS and they did not get black like this. The rubber boot on this one had very minimal melting to it as well.
These coils have approx 3800kms being run on the Haltech.
So before I replace them... I want to try to figure out what I can to do ensure it dosen't happen again. I was thinking to try a 2.5ms dwell cycle since some people have been running these Toyota COPS at 2.5ms without issue.