Hi, everyone! My 1993 240 suddenly lost 4th gear. I read online that a bypass kit can fix this issue permanently, so I bought a bypass plate and when I checked under the car, there was already a bypass plate installed! With confusion, i then removed the old bypass plate and installed the new one, still no 4th gear. I also replaced the corresponding fuse and a known-working overdrive relay, but no luck. As far as my knowledge goes, if there is a bypass plate installed, neither the fuse nor the relay will matter, is it correct? Also, thanks ahead for any advice on how to make my 4th gear work again! Have a nice day!

 

You are correct - all of the electrics - switch, relay, wiring related to the overdrive solenoid are simply there to power the solenoid - and it's no longer there.

Your 4th gear is not working due to a mechanical problem inside the transmission - either in the valve body or the clutches. That transmission is purely mechanical, it shifts due to changes in fluid pressure. You'll need someone with that old school knowledge.

 

A stuck transmission kick-down cable can also keep it out of 4th gear. Check to see if the kick-down cable is binding. It is the lower cable connected to the throttle body. Make sure that it retracts normally upon release of the accelerator pedal.

 

Thank you for your reply, guess I’ll try to loosen the plate and start the car as my last try then, btw do you think if I take it to a shop, will the repair be costly? Appreciate it!

 

That's a different way to drain your transmission fluid, but will be effective.

 

By doing so I was expecting it to blow out the stuff that blocks the 2 passage where the bypass plate sits on. Hope it works.

 

I also own a 1993 Volvo 240 and upon bringing it to the mechanic for a different issue, he told me that the fourth year was not working and told me that he was planning on drilling a hole in the solenoid so it doesn’t encumber the transmission fluid as a bypass option. I don’t know exactly what that means because I’m not a mechanic, but rather than the failing solenoid, not allowing any transmission fluid in, drilling a hole in the plate would allow free fluid passage, thus unlocking for gear, if the transmission isn’t further damaged. I haven’t been driving it much above anywhere above the second gear range since my knee surgery so I didn’t notice anything but I bought the car and it’s always been like that so I might’ve just not been aware of the issue when I bought it.

I'm dropping it off at the shop on Monday for him to determine whether or not this is a fix. He’s been working on them since they came out of the factories and he’s a new mechanic to me so wish me luck and perhaps what I find out could help you too if you haven’t solved it already.