GX460 Random ECU Freak out

[ChiTown]

So I'm driving around like normal yesterday and my 11' GX460 just decides it hates life and starts to spit and sputter like misfire and of course all the lights come on on the dash.

I pull over and pop the hood to see if there was anything obvious, there wasn't.

I shut it off and restart it and it's purring like a kitten with no lights on the dash.

I get home and check for codes, none found.

It's been fine since that, but has anyone else had this happen?

 

[ChiTown]

Hopefully it doesn't happen again but I might throw my spare code reader in the truck just in case

 

[ChiTown]

So I found a thread on a GX470 doing the exact same thing and it ended up being a bad coil back feeding spark energy in to the ECU.

Knowing that our trucks use the same crappy Denso coils as the GX470 I'm going to swap mine out for the same performance coils that I had in my GX470. They're cheaper than the Denso coils and added a little more to the 470 on the butt dyno

 

[ChiTown]

I have looked for current and historical codes, nothing there.

I replaced the coils and the truck runs better and actually got a bit more mileage on the last road trip but still had a bit of an issue.

I talked to a friend of mine at Lexus Tech line and he's thinking EGR valve or primary O2 sensors.

Without freeze frame data or a good log of live data when it happens this is irritating

 

[ChiTown]

Took apart the upper EGR system (valve and pipes) found the pipe to pipe connection in the front had a gasket issue due to the studs not being reinstalled correctly by the tech who "fixed" the coolant leak at the cooler. I replaced the gasket and tightened the hardware and it seems to be good now.