ECU getting very hot..?

[Good & Tight]

Guys how hot does the bottom of the ECU get..?
Mine after 45min of driving it gets very hot were you can put your hand on the bottom of it and hold it for around 8 sec then have to take your hand off from the heat.
It does seem to cycle though, were it's not as hot at times.

Is this normal..?

Also have two grounds to frame, one from the oil pan the other from the back of the head.
ECU is just laying in the glove box.

[e30trooper]

maybe its heat from the turbo down pipe?

[Farbin Kaiber]

^ lol. Is there any resistance close to out of spec on any sensors? I have felt a few 24v DME's, and they do warm up, but not to the burn your hand point.

[hoveringuy]

Mine will get warm, not hot.

[moatilliatta]

Don't the injector or coil drivers in those ecu's known to go bad.

[Dominic49]

i would deffinely ground the ecu itself otherwise it likes to run warm.

[matt]

If you can touch it for 2 seconds, it's not hot enough to be a problem.

[Jean]

Mine gets hot (can still hold though) as well, and it just sits in the glovebox too.

[MattM]

ground the ECU properly. it used the metal grounding to disapate heat aswell.

mine is warm when properly mounted...

[Jean]

It's interesting how some (not all) e32/e34 cars (and maybe other models too) have a FAN inside the box that houses the dme and relays etc. Fan is controlled by a temp switch inside the box....

[briham89]

It's interesting how some (not all) e32/e34 cars (and maybe other models too) have a FAN inside the box that houses the dme and relays etc. Fan is controlled by a temp switch inside the box....

It shouldn't be to hard to make one using crap from kragen....weekend project :)

[Good & Tight]

Drove it to work and back today 75 miles round trip, no problems at all. I guess they do run fairly hot. Still going to add a heat sink and small ecu fan.
Thanks for the replies.