03-22-11, 10:52 AM
I have a 1997 Cadillac Catera. I recently had a used engine (81,000 miles) installed since the old one was bad. I did not install the engine myself, I had the dealership do it. Everything seems to be working fine, except my oil pressure is spiked. At idle the pressure is fine (about 30 psi). As I accelerate the oil pressure shoots up. It maxes the gauge out at about 50 mph. I have noticed that when the car shifts, and the rpms drop, the oil pressure drops simultaneously. And then climbs again as the rpms increase with speed. But again, after about 50 mp it reads 80 psi. The oil light is NOT turning on, and the engine is running quiet, smooth, and at the normal temperature. The only thing I can think is maybe the oil pressure valve is stuck or bad. I just need some input before I bring it in again and sink any more money into it.
03-22-11, 01:03 PM
Im wondering if there is a faulty gauge in the system or bad sender.
Also there is a check valve on the system once above 65psi it opens so your engine wont build excessive PSI... so if anything the sender on the old motor could have the wrong signal and thus show higher readings on the gauge.
I run 10W40 oil in my engine all year round with solid pressure but maxes at 65... drops to 30 and when driving it floats up and down... depending on the load and RPM...
03-26-11, 01:07 PM
Mine does that as well. Sometimes, the needle actually gets to the left of the 80. Not sure exactly when it happens, but I have seen it during the warm up cycle when accelerating. Sometimes the oil drops way down to just above 20, usually on a hot day. One of the disadvantages of having an oil pressure gauge in your car is that you start to watch it and notice things that cars without oil pressure gauges you wouldn't even know. Worth taking it back to the dealer, though, since he just did so much work for you.
03-26-11, 07:03 PM
Id say faulty pressure sender!