I have a 2000 Accord with the V6 and recently had the transmission rebuilt. Right after getting back the car, I noticed a slight shudder at stop lights and my transmission position gauge on the instrument cluster wasn't lit for whatever position the shifter was in. Also the check engine light came on. I took it back to the shop and have been told that the shudder was a broken motor mount, which I saw the engine rocking some when it was run through the gears by their service manager. The check engine light apparently came from the automatic transmission range switch having a problem. From what I've read, this doesn't tell the TCU what gear you're in and may cause some problems with shifting. I know for certain it negates the cruise control. When I drive the car it shifts just fine. My main question to you all is my motor mount has the vacuum assist. Would this in any way affect the vacuum assist and allow the motor mount to not work properly or is it just a coincidence? I would hate to have the mount replaced and not need to. The first time I noticed the check engine light was right after I felt the first shudder. I appreciate any thoughts you guys have.

 

You should find out what code was presented and post that code. It may reveal more about your problem.

I don't think a transmission code would affect vacuum supply to the engine motor mount. Vacuum is supplied when engine speed is low. I could not find any description of the motor mount vacuum control other than a solenoid valve switches this supply on/off. I would suspect ECU only enables vacuum supply whenever idle is below some rpm limit, perhaps 1000 rpm.

good luck

 

No, it needs the range switch.

The solenoid is switched based on whether it's in gear or not.

The mount goes soft at idle in gear (R or D).

The mount goes hard in P or N or anytime it's not idling. I don't know whether it uses RPM or TPS to say when it's not idling.

 

I'm going to get the switcg replaced today. I'm hoping that this also fixes the mount problem. If not I'm going to have to get the mount replaced this weekend.

 

After fixing the trans switch & before replacing the mount, check the vacuum-control system.

- Loose or broken vacuum hose leading down the mount?
- Bad electrical connection at the solenoid valve?

You can test the mount system...
- Have someone put the car into D or R and hold the brake.
- Reach down & unplug the electrical connection to the solenoid.
- That should make a big difference in the smoothness of the engine (felt by the driver).

 

The code was P1706. As for the switch, the shop is giving me the run around. Why? Because I already paid them, but hopefully the switch will get done Tuesday. I'm hoping that it takes care of two problems at once. We'll just have to see.

 

Well I got the switch replaced this week and the issue with the mount seems to not be happening at stop lights or from dead starts, but does seem to be still happening when I go from neutral to reverse or drive. If I run through the gears in a relatively normal speed it seems to work just fine.
But now I have a new problem. My starter won't seem to engage from time to time. It doesn't seem like a dead cell on the battery. It's acting like when you leave the car in drive and try to start it, no activity at all from the starter. I'm going to take it down to the dealership tomorrow, if it'll start. I don't think it's anything that the other mechanics done, unless the range switch was out of whack or something, but if that were the case then I'd think the check engine light would be on again. I'm guessing that there's a relay on the starter that may be going bad. I've got a friend who had that happen on the starter on his Sebring a couple of years back and it's doing the same thing.