Serious grinding and fluctuating oil pressure. Please advise.
 

Not on my car, thank god.

This is on a longnose 1.6 in a 92. The car was driven 200 miles with no front main seal and run at least two quarts low on oil. After installing a front main seal and performing the "put 4 quarts of oil in" mod, the car ran like a champ, but it has suddenly started to make serious grinding noises and the oil pressure is fluctuating. I am thinking oil pump gears, but I wanted to get ideas from you guys as well. I may have access to a blown 1.6 (rings) with good OPGs so if they are the culprit we can just swap them in and be done.

bearings?

In the motor itself? I'd think that would show up as a tapping noise. This is more of a grinding nose, apparently. The fluctuating oil pressure is what's pointing to the pump or gears, at least in my head. Idle is stable.

Does the car have 6 qts of oil in it now?

Oil pickup tube could be clogged. Happened to my CRX a few weeks ago. The bad news is you have to pull the motor to get the pan off and you might as well stuff a newer motor in if you are going through all the labor anyways.

gears. This sounds like the Contour SVT problems with oil starvation and smoking gears. Its pretty cool that someone drove that car with no front main...lol.

Maybe it's JDM YO and has a bigger sump than normal.

...yeah, that would be me. All highway, too. Imagine what a racecar looks like with a blown engine (the contrail of thin white smoke) and then imagine a Miata doing that for 200 miles. ;) We had no idea why it was burning oil so I just kept driving. If SLO was 210 miles away vs. 200, I probably wouldn't have made it; the car started to drop oil pressure when we pulled in around 3am.

The car has 4 quarts in it. We filled it ourselves before the trip (the car had just come out of the shop and it was not done, long story) with a full 4 quarts and my friend said he put an additional 2 quarts in after he did the front main seal and TB over again. (shop obviously fucked that one up.)

Looks like the motor is coming out. How hard is it to get to the oil pump gears? I might be able to source another blown 1.6 and pillage the gears from it.