[baron62]

Hi,

I have a 2008 328xi with 98K miles that runs great, but it is leaking oil around the valve cover gasket. I will replace the valve cover gasket and soleniod gasket to stop the leak. Should I also replace the Eccentric Shaft Sensor? I would rather not at $400. or is this a standard replacement item? Any other gaskets I should replace while I'm in there? (like the one around the Eccentric Shaft Sensor?)

Thanks

[F22_Raptor]

Yes there is a gasket around the ESS that needs to be replaced. Is there any oil in the sensor its self? If so, you should definitely replace when you do the VCG.
In addition to this, you should also replace the gasket around the valvetronic motor.

[dstrickland]

If your not getting any codes or don't have a fluctuating idle, then as of now, no need to replace the sensor(as the above post said, check for oil in the sensor where it plugs in...

But as a heads up..we do see these sensors fail fairly often, but one of the main reasons they do is because oil leaks past the gasket & gets into the sensor. You replacing the gasket when doing the vcg may prevent that.

[Willsbma]

Just my .02 but I wish I would have done it when the valve cover was off. Basically for peace of mind, but I also feel like they partially fail and compromise performance, but don't trigger a CEL

I have 101k and I only changed the gaskets when I did my VC at 81.5k

[tlow98]

Originally Posted by Willsbma

Just my .02 but I wish I would have done it when the valve cover was off. Basically for peace of mind, but I also feel like they partially fail and compromise performance, but don't trigger a CEL

I have 101k and I only changed the gaskets when I did my VC at 81.5k

What makes you think they partially fail? Not instigating genuinely would like to know. I'm coming up on these mileages...

[Willsbma]

Originally Posted by tlow98

What makes you think they partially fail? Not instigating genuinely would like to know. I'm coming up on these mileages...

I was monitoring the sensor with INPA and it was coming up in the red of the accepted range. I would imagine if it went 100% bad, it would be way out of spec and trigger a CEL

Working "out of spec" is what leads me to believe they go bad gradually

I may be 100% incorrect but I've been chasing a slight throttle-input stutter for a while and that's the only thing I can really attribute it to, or a faulty pedal sensor.

[baron62]

Thanks, I have ordered the parts.

[hassmaschine]

If it aint broke...

[tlow98]

Originally Posted by Willsbma

I was monitoring the sensor with INPA and it was coming up in the red of the accepted range. I would imagine if it went 100% bad, it would be way out of spec and trigger a CEL

Working "out of spec" is what leads me to believe they go bad gradually

I may be 100% incorrect but I've been chasing a slight throttle-input stutter for a while and that's the only thing I can really attribute it to, or a faulty pedal sensor.

Interesting. Good to hear about INPA's capabilities. Might have to take the next step beyond Carly. Thank you

[Willsbma]

Originally Posted by tlow98

Interesting. Good to hear about INPA's capabilities. Might have to take the next step beyond Carly. Thank you

Funny, I was thinking of giving Carly a shot. I hear you can monitor live through there also and I wanted to set up a small, dedicated tablet in the glovebox for on-the-fly logging. The laptop gets cumbersome compared to that setup

[matteblue3er]

Originally Posted by dstrickland

If your not getting any codes or don't have a fluctuating idle, then as of now, no need to replace the sensor(as the above post said, check for oil in the sensor where it plugs in...

But as a heads up..we do see these sensors fail fairly often, but one of the main reasons they do is because oil leaks past the gasket & gets into the sensor. You replacing the gasket when doing the vcg may prevent that.

The oil does not leak past the ESS sensor (edit: sensor seal) into the connector. The connector sits higher than the seal so this is not possible. The oil leaks through the metal plate on the back side of the sensor, up into the connector.

Originally Posted by tlow98

What makes you think they partially fail? Not instigating genuinely would like to know. I'm coming up on these mileages...

When you see oil inside the connector and around the pins, that's when you know the sensor has "partially" failed. While the sensor may still be ok, the oil adds capacitance to the sensor readings and causes it to go out of spec.

[talisman311]

Remove the plug and check for oil inside. If you see oil, I'd go ahead and replace the seal and hope that your sensor is ok.

I used brake cleaner and compressed air to clean mine out over the course of several weeks (I think oil seeped up the wiring harness, so I'd see the oil reappear). It's been roughly half a year and the idle/throttle response seems ok still.

[Nurf]

baron62

Originally Posted by baron62

Hi,

I have a 2008 328xi with 98K miles that runs great, but it is leaking oil around the valve cover gasket. I will replace the valve cover gasket and soleniod gasket to stop the leak. Should I also replace the Eccentric Shaft Sensor? I would rather not at $400. or is this a standard replacement item? Any other gaskets I should replace while I'm in there? (like the one around the Eccentric Shaft Sensor?)

Thanks

Dude, Don't even bother Fixing It yourself, If you are in CT like your Profile says ITS COVERED UNDER SULEV WARRENTY from BMW, I live In CT and got mine done 100% covered along with Vanos

[matteblue3er]

Originally Posted by talisman311

Remove the plug and check for oil inside. If you see oil, I'd go ahead and replace the seal and hope that your sensor is ok.

I used brake cleaner and compressed air to clean mine out over the course of several weeks (I think oil seeped up the wiring harness, so I'd see the oil reappear). It's been roughly half a year and the idle/throttle response seems ok still.

Again, the seal on the valve cover does NOT cause oil to get into the connector.

The seal prevents oil from leaking out the valve cover, around the sensor connector.

There is another seal on the plug harness that seals the opening for the connector.

If you look at the design of the connector and plug, you'll see that oil cannot seep passed the valve cover seal, up over the connector, then down passed the plug seal and then into the connector.

As I mentioned earlier, the metal plate on the back of the sensor fails and allows oil to seep into the sensor itself and wick up the sensor pins.