DTAForum.com - a forum for the DTA ECU

It's not just a DTA issue. A guy I know had an M800 on an Evo burn out coils randomly also when sitting with key on. Seemed to be in trigger was in just the right spot. Different issue I know, but I'm just saying that other supposedly premium brands aren't exempt.

I would make it usual practice to trigger coil power relay with the fuelpump trigger. I would imagine that the ECU while trying to communicate is dropping the config for whatever reason and the outputs are going to their "rested" state.
I assume you've checked your serial driver is correct, I've struggled to connect with a Prolific cable unless I had the one DTA has on their website installed.

direct serial should require no drivers ?

It seems the crux of the comms issue here maybe pushing the ecu into an unknown state is the length of the cable used.

But wiring coils as you describe does make a lot of sense for this sort of application. Others have mentioned it before because of an initial key-on firing all the coils which can sometimes give a little kickback or ignition of any fuel lying in the engine.

swsupermoto wrote:I've burnt 4 out on a millington with k20 oils and never found out why. Interesting

Now that worries me I have 4 coil packs from Brands Hatch Performance I hope we won’t have the same issue !

If you're triggering them right, they should be fine. And relayed via FP output for extra insurance.

stevieturbo wrote:If you're triggering them right, they should be fine. And relayed via FP output for extra insurance.

Would earthing the relay via the oil pressure switch also help - no pressure = stopped engine = no potential bangs / kick backs and engine must be spinning first to get oil pressure and again no chance for kick-backs?
Also turning an engine over first without ignition helps a lot with those with raised compressions or overly advance idle ign timing!

stevieturbo wrote:If you're triggering them right, they should be fine. And relayed via FP output for extra insurance.

Not allowed for any relays to trigger the coils in the new loom as we thought you could fire them from the ecu directly?

All circuits that you turn off on at any point will generally require a relay.

That has nothing whatsoever to do with how the ecu triggers the coil.

Huxley wrote:

stevieturbo wrote:If you're triggering them right, they should be fine. And relayed via FP output for extra insurance.

Not allowed for any relays to trigger the coils in the new loom as we thought you could fire them from the ecu directly?

You can fire them from the ECU directly. The problem in this thread is the first time I've heard of this, so it must be something specific to this setup.
I run amplified coils on mine.

The idea behind powering a relay for the coil 12v supply is that the coils will sometimes fire when the ECU starts up. This is to do with how the coil drivers power up.
If there is fuel in the cylinders, this can sometimes cause a backfire.

Powering the coils from the fuel pump relay ensures the coil drivers can start up with no power to the coils, and then the coils will turn on afterwards.

I use a switch with three positions.
Up - everything off.
Middle - ECU and fuel pump on
Down - all other 12v items powered

This means I can power the ECU up without powering anything else. It also gets around the coils firing when powering up.

Don't see how that gets around the problem? If power for the coils / ECU / coil drivers becomes live at same point and if the engine is in the correct position with fuel present that backfire scenario is a possibility! My solution adds another relay but the coils won't be on EVER unless the engine is running!

We're talking electronic component time here, not human time. It may appear they all come on at the same time, but they don't.

The ECU turns on, which turns on the coil drivers=s, but leaves all other outputs off. It then runs all the initialisation routines, which includes reading the map.
At this point, before the fuel pump relay is turned on, it knows that the coils are amplified, and modifies the output.
However, this could be enough time to charge the coils just enough to emit a spark, before they've been turned off.

Later on (in electronics terms, it's instantaneous to us pink squidgy things*), the fuel pump relay turns on.

So powering the coils from the fuel pump relay resolves this issue.
This isn't something I've just come up with, it's been used for years, and is known to work well.

* My favourite new term...