Misfire question... Sensor or Coil?

jamesbekman · Post by **jamesbekman** » Fri Jun 01, 2012 3:46 pm

Hi,

Brent I saw in a previous post that you stated that if the VR sensor mount is vibrating that it can cause a misfire. I have a rough idle, more like a miss happening... The other problem could be a coil that I can swap out.

tested plugs and wires... all is good.

Here is a video of the car at a low idle speed. about 750-850

http://www.youtube.com/watch?v=JjYIc0I7rxY&feature=plcp

Is there anything else I could look into?

Thanks,

James

jamesbekman · Post by **jamesbekman** » Fri Jun 01, 2012 4:01 pm

Here it is with the idle turned up and mixture leaned out a little

http://www.youtube.com/watch?v=Vleq7CN3WiA&feature=plcp

jamesbekman · Post by **jamesbekman** » Tue Jun 05, 2012 1:55 pm

Seems I have a compression issue... Pulling the head...

jamesbekman · Post by **jamesbekman** » Fri Jun 15, 2012 5:46 pm

Ends up I didnt have to pull the head. The valve wasnt closing all the way on cylinder #4. I hope to post more video of a nice idling mgb with my megajolt setup this weekend.

Post by **brentp** » Sat Jun 16, 2012 5:36 pm

Wow. checking compression should be a standard question. However, many megajolt troubleshooting sessions come with the assumption that the conversion happens quickly with an engine in a known-running state. I'd imagine that some installations are on engines that haven't run for a while, or, how well it ran on distributor is not known.