Hello Fellow 7th gen survivors!

Hi folks! I'm the proud owner of a 2004 Civic EX 4dr Automatic I use as a commuter car but also enjoy the occasional brisk romp around these twisty mountain roads around my house in Patrick Co.
(for a thrill try google streets on SR40 out of Woolwine, or SR8 down from Tuggles gap)

I recently suffered through the overheating/head gasket problem common in the D17a2 engine and joined to share my findings, and give back a bit after finding the posts so helpful along the way.

****I haven't used this type of forum very often so I thought I should ask: is it okay to add my thoughts to the old threads (on this issue) that I used during diagnosis? I have new information that might help and would like someone to test a theory when they start troubleshooting the same problem which I think would be worth trying before tearing the whole engine down.

I think it's actually exhaust gasses leaking into the coolant in the water passage/EGR assembly and not a head gasket.

No white smoke, mixing of fluids, loss of compression or fouled plugs which normally indicate a blown or leaking head gasket(HG) made me wait a very long time before taking on the task of replacing it, and only the presence of exhaust smells in he overflow finally caused my to buy a gasket set and start work. When I saw this arrangement while isolating the head for removal I thought it might be related, but was already well into the job so I continued the HG without trying it.

It makes more sense to me than a blown HG because the EGR gasses are post combustion chamber and not subject to intake vacuum so no water would be sucked in on the intake stroke. The gasses would also stink up the coolant. The water passage/EGR manifold uses a crush type gasket but the shop manual doesn't detail a torque cycle or spec, a level and flat check or any other special service of this component...which I didn't like during assembly and used a torque wrench cross pattern and took it to 28lbs per bolt specs. I'd like to see others test this as a standalone project/solution before tearing the head down. it could save us all a ton of time and cash.
In short: Just replace the Water passage/EGR manifold gasket to stop it from blowing water into the overflow...maybe.

I hope this helps someone in the future.

Wheels down!