There's an ATRA bulletin out about a defective EGR valve causing a TCC-like shudder sensation at lower speeds. I've only had one vehicle do it and it felt more like a lean engine miss to me. The diagnostic procedure is to disconnect the lines from the EGR valve and see if the problems go away. I'd provide a copy of the bulletin, but I'm already on TiNA's bad side.

The Odysseys have a serious problem with cooler/converter oil flow when hot and in lockup. The oil exiting the converter is always directed to the cooler. The converter charge oil (fluid going in) is what applies the TCC. The pressure difference between the converter charge oil on the front side of the TCC piston, and oil exiting the converter on the back side of the TCC piston is what applies the TCC piston.

What ultimately happens is that the flow of ATF in and out of the converter effectively falls to a trickle (or stops all together) and causes a low clamping force of the TCC piston on the converter cover (face). This slip is not smooth and it's a very quick "slip-grab-slip-grab" repeatedly like you're driving over a washboard road.

A lean engine miss under load can often duplicate this feeling and I've seen it misdiagnosed by some really sharp techs. The reason this takes place is that when they disable the TCC, the problem seems to go away. What's REALLY HAPPENING is the lean engine miss is STILL THERE, but you can't feel it because NOW the converter isn't locked up and the fluid coupling nature of the torque converter hydraulically dampens out the lean engine miss to where the driver can't feel it any more. The miss is STILL THERE. You just can't feel it because it's being dampened out.

Take it from a transmission man who knows.

Larry Bloodworth
Technical Information Specialist/Technician
Tanner Transmissions
Draper, Utah, USA