Ok, so I've been around here forever, but I'm new to the 4G63 scene. I just picked up a 99GST and it's leaking oil pretty good from the drivers side in a spatter pattern. I had it checked and my mechanic said it's coming from under the timing belt cover. After some research it seems the front oil pump seal is a common culprit on thesee cars. Any .02 from you guys?

Most likely that's what where it will be coming from. You can't know for sure till you pull off the lower cover and check.

I don't think I'm even going to do that. My plan right now is to pull the whole motor in the spring ... replace all the gaskets (I already bought a gasket kit) and do a new oil pump, water pump, and timing belt all at once. Hopefully I'll figure out what it is then. Thanks for the reply.

Yes common culprit BUT keep in mind that the cover runs up to the cam gears. Oil can leak anywhere in that area and leak out of the bottom of the cover. Like Tony says, gotta pull off the cover and look. On the bright side, there are just 4 bolts to pull off the pulley :thumbsup

MB

Yeah ... I'm certainly not going to miss the days pulling out the harmonic puller just get that damn NT pulley off.

Could be coming from around the oil pan where it meets up with the oil pump, ive seen a few leak from there...

Whatever it is I'm hoping it becomes very obvious once I get the motor and get that timing belt cover off. I'm scheduled to pull my motor in April.

Did you check to see if the timing belt has oil on it? My front seal and oil pan was leaking (still is x.x) and it covered the belt and shot out the bottom of the drivers side. Talk about a pain, after 3 attempts something STILL leaks.