tomf

Has anyone replaced the front motor mount on a 99 es300 with vvti? What's the difference between the front motor mounts for engine's without vvti and those with vvti? The reason I ask is because all the motor mounts I've seen on the web specify without vvti. Thanks Tom

LeX2K

There are 2 types, regular mount and active. You can easily tell what you have, look for a connector/wires going into the mount. Active version may be a dealer only part not sure.

tomf

Thanks for the insight, Lexus2000. I've looked at the mount. There are wires that seemed to be attached to the mount but not going into it. I've attached a picture. Maybe you have a better idea of what to look for than I. Thanks.

P.S. My research indicates that the 99's had an Active Control Engine Mount. Was this an option or come standard? Did some of the 99 es300s not have an Active Control Engine Mount?

LeX2K

I'm not sure, try looking up the parts at toyodiy.com. Failing that, call a Lexus dealer and get a part number and go from there.

I did a bit of searching and didn't come up with much, but I think starting in 1999 they all had the active front mount.

tomf

I'm pretty sure that it's active. I found a site that lists parts and various model's and there are two different front engine mounts. One for VVT and those without. Mine is VVTi. I guess I'll have to look closer at the wires. I also saw a thread asking about a Vacuum Switching Valve that had a line running into the mount. https://www.clublexus.com/forums/es3...999-es300.html I guess I'll be buying it from a dealer.

LeX2K

What makes you think the mount is bad?

tomf

The reason I'm thinking it might be bad is that sometimes when I accelerate from a stop I hear a clunk sound. Not sure from where the clunk is coming. I also looked to see if the engine moves when I put the ES in drive, reverse and step on the accelerator with my foot on the brake. I all cases there seems to be significant movement of the engine. Based on my research those are indications of bad motor mounts. I'm just in my research phase now. I hear the rear mount is a real B.I itch to replace because the right drive axle goes through the same bracket that holds the motor mount. But the dog bone is easy. So I'll do the easy stuff first and see if there is any improvement.

If you have anymore insight please keep it coming

LeX2K

I've done a rear mount replacement, it's not easy. The other mounts are a piece of cake in comparison. If you do start replacing mounts, then do them all at the same time, otherwise the weakest mount will be stressed and it will fail quickly. This is especially true for the dog bone, people that have replaced a rotted out one had it fail shortly afterward because the other mounts were also bad.

I would go OEM on all the mounts if possible, depending on the price.

nhstevehz1

Sorry for jumping in late (newbie here).

Yes, that is an active control mount. The wire is connected to a control valve that modulates vaccum to the mount at an opposite frequency to the vibration of the engine. This smooths out any vibration the engine may create at low rpms.

To remove, loosen the transmission mount nuts (or remove them completely). Remove only the nuts that fasten the mount to the sub-frame. You will have to remove the two plastic hole covers from the sub-frame to get at the nuts.

Place a floor jack under the engine to support it. I used a block of wood as a cushion. Place the jack toward the front of the egnine (LH side). Remove the bolt on top of the mount and the three that fasten to mount to the sub-frame. One of the bolts is removed from underneath so you will have to remove the cover under the car to get at it.

Remove the vacuum valve connector and release the clamp that holds the wire to the mount.

Raise the engine with the jack until you have enough clearance to remove the mount from underneath. I also removed the hydraulic damper (it looks like a mini shock absorber) to provide extra clearance.

To bench test, remove the vacuum hose that connects the valve top the mount. Coonect a vacuum tester (such as a mighty vac) to the mount and create about 25in hg of vacuum. If it holds for 1 minute, then the mount is OK. Replace if the vaccum drops even a little. The mount contains a fluid. Check the bottom for any leaks.

To bench test the valve, check the continuity between the two connector terminals. It should read between 19 and 21 ohms. Check the continuity between each terminal and the metal housing. If there is continuity, replace the valve. The part number is located on the blue and grey tag that you show in your picture. Look at the blue part of the tag for the toyota part. The bottom part of the tag contains the Denso number.

Sorry I don't have any pictures for this.

I agree with Lexus2000. I would use only OEM parts for this but they are not cheap.

For part numbers and pricing, try lexuspartsnow dot com. The prices aren't bad but you may be able to find other sites that are a bit cheaper. I also use parts dot com.

Good luck!

tomf

Problem solved. Two of the bolts on the front engine mount were extremely loose. I tightened them down and clunk is gone.

FYI: another symptom was a single clunk when I turned either direction. It sounded like something was shifting in the engine compartment. I only discovered the problem by observing the front motor mount when my wife put the car in drive and pressed the accelerator. Then it was obvious.

Thanks for everyone's help.