My car recently had a new main oil seal. Now when I brake to a stop the oil pressure gauge hits zero an the oil pressure message come up. As I accelerate it goes back to normal. Any ideas??

Separately I notice when accelerating gently above 20mpg I get a rough/vibration/rubbing noise. Any ideas??

thanks!

 

Welcome to the forums bchase,

That needs prompt investigation or something could go horribly wrong.

The oil pressure gauge is only a rough indicator but dropping to zero clearly shows there's some problem. It could be as simple as a faulty gauge or sender but it could also be a blockage or failing oil pump. There are various diagnostics which can track oil pressure but these rely on the signal from the sender and the only true way to get actual pressure is by tapping into a line and checking with an external gauge.

You recently had a new main oil seal which I would take to be either front or rear crankshaft seal? If you didn't DIY then I'd take the vehicle straight back to wherever the work was done. This is too much of a coincidence.

The rough/vibration/rubbing noise is very worrying. With zero oil pressure, the main bearings soon run dry and a failed bearing has a rumbling sound. However, I see you have an early 1996 model and these have two particular issues:

1. nikasil coated cylinder bores
2. plastic timing chain tensioners

Rapid nikasil wear was a major issue shortly after the model was intoduced. High sulphur content in fuel rapidly wore the coating resulting in lost compression. However, sulphur was long ago removed from fuel and any Nikasil lining that has lasted this long is very unlikely to give any problems.

Plastic tensioners are a different matter. They can break with catastrophic results. Timing chains jump on sprockets and valves then collide which almost always destroys the engine. If your engine still has the original tensioners, they could be breaking with pieces falling into the oil pan and blocking the oil pick-up.

Some further details on the recent work may help target a more specific cause of the low pressure.

Graham

 

Confusingly, the source of the oil pressure gauge is a simple switch, on and off, there is no continuity of any kind.

I would add just a simple observation to @GGG 's post above: double check the viscosity of the oil, and make sure is matches what the engine needs at your location (check the owner's manual). This is likely a paper exercise to double check your records, or call the shop that last did your oil change. If it proves inconclusive, you might want to go ahead and change the oil/filter with the recommended product.

 

To emphasize what’s been said above - do not drive this car until you determine what is going on with the oil pressure drop. This could be horrendous and very $$$$.