ECU heat soak

[Jean]

Yep, the factory dme / fuse box on donor cars has a temp switch that turns the fan on for cooling . It would be quite easy to mount a 12volt fan to the bottom of the glovebox (obviously with first making some vent holes ) and have it cool the dme as needed.

[WYZEUP]

Being a RHD the dme is in the same location but above the pedals instead. Next time I have the car I will remove the kick panel and when it starts misfiring will check how warm the dme is....
No check engine lights…..I may have to check all my connections of my loom adapter, seems strange it only does it when the ambient air temp is high, otherwise runs flawlessly.
Could the dme relay cause these issues? I did notice once when the kick panel was off and it started misfiring every time you touch the accelerator a relay under the dash would click?

I’m really just spit balling ideas to try get my head around what may be causing the issue.

[Zacm829]

Yep had this problem on my m62 swapped e30 while on the track in the summer. Ecu extremely hot to the touch. Ended up wiring in a computer case fan and thermally bonding an aluminum heat sink to the ecu casing. Problem solved.