Hi Guys,

At just a little over 200k miles, I brought my car to the local indy due to plugs fouling in several cylinders. It was diagnosed with worn valve guides and having low compression in a couple cylinders. A leakdown test was also done, but I don't know the results. The head was taken off for machine work and the pistons were soaked in a magic concoction (I don't know what they used), which apparently freed the rings and brought compression levels back up. The timing chain, waterpump, and belt tensioner were also replaced as they were worn out.

The main issue that I'm still having now is with low oil pressure when the engine is idle. At cold startup, I get 3 bars in a couple of seconds. As the coolant temperature rises to 80, pressure drops to less than 1 bar. When coolant temperature is 100, pressure drops to zero or very near zero. The owner's manual specifies that .3bar is acceptable, but I really don't know where .3bar is on the gauge since there's no mark for this. I'm pretty sure that the oil pressure sender isn't the problem, since I've recently swapped it out for a new one (VDO). There are no noises from the lifters, and pressure rises immediately when rpm's go up.

I asked my indy about this, and was told that it's normal. The shop used 10w-30 dino oil, but I've had similar results using 15w-40 in the past. I've made an appointment for them to check the pressure using a mechanical gauge but haven't had a chance to bring the car back to the shop yet.

From what I've read, low oil pressure could be caused by worn bearings. Is there a temporary fix available for this, maybe running thicker oil would help?