Help Trouble shooting a potential head gasket issue


New Member
Hey guys just got a 87 GN, which was my childhood dream car. It has 72,000 miles on it almost all original.

So far I replaced the coolant, tranny fluid and filter, diff fluid, 02 sensor, a couple rad hoses, plugs Auto lite AP 25 gapped to .35, 8.5mm wires, serp belt and by passed the leaking heater core. I'm awaiting on the new pcv valve and fuel filter.
I have also added a electric cutout on the down pipe and removed the cat.

So under acceleration the car things are OK, when at idle there's quite a bit of white smoke coming out the exhaust, and I smell some oil inside the car. While driving everything seems fine power wise. The idle is not great while in drive, it feels like it has a mild cam. I'm sure it's a result of a vaccum leak and possible misfire. It's getting a smoke test this week.

I know there is a small transmission cooler line leaking on top of the lower rad hose. I will have to fix that soon.

I just got the scan master and will install it today.

I don't see any coolant mixing with oil inside the engine but I'm concerned about the white smoke at idle.

Could the white smoke be a result of a poorly tuned car with no cat?

You guys are the experts, this technology is new to me.

Any advice or help would be greatly appreciated!