Sporadic oil leak

I'm3rd · Feb 21st, 2006, 02:42 PM

My daughter's '92 Sentra with 1.8L engine and 145K on the clock has developed an oil leak which baffles me. Sometimes it will be down 2 quarts just 3 or 4 hundred miles after being full. Other times she can drive it over 2K miles and only need 1/2 to 3/4 of a guart. A mechanic took a quick look at it and told her the front and rear main seals are both leaking, but why would they only leak part of the time?
I have heard that the oil pressure sensor is prone to leak on that engine. Could it be leaking sporadicaly like this? BTW, my daughter wouldn't know the sensor from the transmission and I am laid up with a back injury which keeps me from getting under the car. I am tempted to get my son to go over to her house and replace the sensor whether it's leaking or not. Is that a good place to start at least? I am assuming that the sensor is a scerw in type which would be fairly easy to change out. If it isn't and requires a more complicated job it's probably not something he could do.

Sethticlees · Feb 21st, 2006, 05:37 PM

Well, I hate to say it but the mechanics suggestion of front & rear main seals is probably correct. Leaky main seals are common occurrence with the GA16DE engine. (1.6L not 1.8) The front main seal is somewhat easy to replace but the rear main seal is behind the transmission and so not as easy a job.

First thing I would do is check the transmission fluid dipstick. (I have assumed this is an automatic transmission; please correct me if I'm wrong)
Look for any trace of motor oil in the transmission fluid.

Any other leaks and she would have nice oil stains in the driveway. Check the engine block, especially the front main seal (it's located behind the main pulley).

Sorry, but I have no experience with oil pressure sensor. Search the forums for more info.

BTW, this post will likely be moved to the GA16DE Engine Forum. You’ll get way more help there then you will here.

I'm3rd · Mar 2nd, 2006, 07:16 PM

Thanks Sethticlees. You're probably right about the seals leaking. I guess I'll tell my daughter to take it to the shop she uses and see what they find.