[4th Gen] Engine/Trans Mounts

[OwnerCS]

Can anyone share their experiences on replacing the engine/transmission mounts for a 4th gen?

I have a 99 model I30 (automatic) and a 95 manual. I know the left and right mounts are gone on the I30 automatic.

Can anyone steer me to a good source for reasonably priced mounts? I see people talking about filling existing mounts with some type of window sealer.

Does the 4th gen use any type of mounts with electric wiring? I see some concerns on the 5th gen with ECU damage occurring if the mounts go bad. Is this an issue for the 4th gen?

I have jack stands and two floor jacks.. I'm fairly quick at strut and axle (with seal) replacements. So I've been successful at working on my 4th gens.. Should I try this at home?

[audtatious]

I've never seen anything about ECU damage due to motor mounts. Sounds kinda odd to me.

Go through the FSM to see how difficult it is working on the I30 mounts: http://www.nicoclub.com/FSM/i30/1999/

Hopefully that will steer you in the right direction.

[OwnerCS]

Here's a post from Loystock about toasting the ECU from a bad electric engine mount or IACV

post6218840.html?hilit=mounts%20ecu#p6218840

It looks like from Loy's post the electric version can be disconnected to keep from damaging the ECU.

I would like to try running without an electric mount. I believe a MT mount is non-electric.. There is about $100 difference in price for the electric mount.

This car already lost one ECU (before I bought it with a bad ECU). I didn't prove the original ECU was toasted by the IACV so I've always been looking for another suspect.

Loystock - please chime in with some experiences.. :-)

[audtatious]

Hm....I didn't remember the motor mount being electronically monitored or controlled.

Been too long without a Maxima-style vehicle I guess

[OwnerCS]

Tonight I unplugged the electric front motor mount.. A local Infiniti mechanic said I won't need to worry about frying an ECU with it unplugged.. So I plugged in my OBD2 scanner and after unplugging the mount, no CEL codes were raised..

[loystock]

I'm sorry for the delayed response. I've been on the road for a while with intermittent internet access, except for my cell phone.

The drivers (power transistors) for the electronic engine mount, just like the IACV, are mounted in the ECU. If there is a short circuit either in the IACV or electronic engine mount, it will most likely 'fry' the ECU. The electronic engine mount is used to minimize engine vibration being transmitted to the chassis when engine is idling or at low RPM. As the engine RPM goes up, the electronic engine mount stiffens. In most cases, you will not feel a difference when the electronic engine mount is disconnected. And yes, it will not trigger the CEL.

[audtatious]

I learn something new every day.