Transmission/Clutch Issue

[James Matteu]

I was helping a friend with her car. She says that her car cannot go into gear while the engine is running. Then while the engine is not running, the transmission can shift into any gear.

 

She drives a 1994 Honda Accord EX Sedan 5-speed manual with the 2.2 liter SOHC VTEC Sequential Multiport Fuel-injected Engine. All stock with a cold air intake.

 

When I got there, she had a lot of air in her clutch's hydraulic system so we bled the Clutch first.

 

Bleeding the Clutch:

I started by removed line going to the Clutch Master Cylinder, poured fluid directly into the Clutch Master Cylinder; then replaced the line. I did this to reproduce the effects of a bench bleed. I then filled the reservoir, put a vacuum line on the Slave Cylinder Bleed Screw and dropped the open end of the vacuum line into a clear plastic bottle with about 2" of Brake Fluid in the bottle to keep the vacuum line submerged in brake fluid. She pumped the clutch, I opened the Bleed Screw and watched as first bubbles came out of the vacuum line, then fluid with smaller and fewer bubbles. I continued to refill the reservoir until the fluid coming out of the Slave Cylinder end had very few bubbles.

 

Clutch Function:

With the car off, I put the car in reverse. I then started the car while holding the clutch in. I let the clutch go with the Emergency Brake engaged, knowing the car would stall since the car would not move. This tells me:

- the Shift Cable and Select Cable were able to select reverse

- the hydraulics had sufficient pressure to move the Release Bearing

- the Pressure Plate was able to “grab” the Flywheel and stall the motor.

With the car off, I left the transmission in no gear. Turned the car on, and then tried to put the car in gear. The Gearshift Mechanism did not go into any gear. I could not even "feel" the gears. It was the same feel as if you try to find 1st gear and the car is moving 40mph. If I pushed hard, the idle would drop.

 

Clutch Electronics:

I have reviewed the system and see a Back-Up Light Switch, Vehicle Speed Sensor, Clutch Interlock Switch, and Clutch Switch. I know the Clutch Switch works with the Cruise Control System. The first time I looked over the car, the plastic stopper the goes in the Clutch Pedal that pushes in the Clutch Switch was missing; I shoved a piece of rubber in the hole as a make-shift plastic stopper. It was still there today, but again, this switch only works with the Cruise Control and should not have anything to do with the normal operations of the transmission. I did notice today that the Clutch Interlock Switch was NOT plugged in. She said that it was the wrong Switch for that car since the connector would not plug in; I verified this and then suggested removing the pins from the connector and sliding them into the female end mounted on the Clutch Interlock Switch.

 

My questions for everyone: What does the Clutch Interlock Switch do? Can it cause the symptoms Macda has been having? She says the connector has been disconnected as long as she has had the car, and it did use to run fine, so I am not sure that this has anything to do with the problem.

[Pballer2005]

quick search said that the interlock switch is what prevents the car from starting while the clutch is not depressed. so assuming what i found was correct, the car shouldn't even start if that switch is not connected. other than that i have no idea