Please help: 172 popping out of 3rd gear at high revs

[jmw1979]

Hope somebody can help with this problem. I have a 53 plate 172, 60 k on the clock. A couple of times the car has popped out of 3rd gear during high acceleration, while the engine continues (somehow) to maintain the revs without my foot on the accelerator. Effectively the car seems to go into neutral, whilst the engine continues to rev unaided with total loss of power - the only way to get the car back into action is to then engage the clutch and slip it in into 4th which solves the issue. A major problem during an overtake though!!:S

This has only happened once or twice, and only ever in 3rd gear under high revs. There are no other noises coming from the gearbox, or problems with the gear shifts which are completely smooth, and the gear box all seems totally A-Ok otherwise. No other issues at all.

Bit of a strange (and worrying) problem, I hope somebody might be able to help??:S

 

[DrR]

Trade it in.

Could be an dodgy mount maybe?

 

[Jonff]

In my other 172, that use to happen but only it 1st at high revs, never did find out why though. As DrRollo says though, could be a dodgy mount.

 

[jmw1979]

Thanks guys. Trade in is an option. What is the cost of new mounts? Might not be a major issue then?

 

[Dave Hester]

3rd gear syncro sounds like it's going to pop. Quite a common fault

 

[jmw1979]

What's 3rd gear syncro? Any idea on the cost to fix the problem.

 

[Dave Hester]

Check out my rs gearbox..............who's had problems thread In Clio discussion

Anywhere from £400-£1000 depending where you go

 

[gtruk]

Sounds nothing like a synchro issue. Specially if you have what you describe as a smooth gearbox. What it probably is and has been said is the gearbox engine mounts. You have the dog bone one on the bottom, and you have a larger one on top of the gearbox under the battery.

Your best bet would be to either replace the dogbone mount at the bottom and check the top one, or go on ktec's website and look for there replacement dogmount/bushes.

I dont see it being a major cost to you, and there is no need to trade in your car That was meant in humour.