2003 Megane 2 subframe bolt does not stick

[JouniMe]

I removed a big 18 mm sub frame bolt from rear part of the front sub frame (right side) and now I can't put it back. It is like there are no threads at all in the other end of the hole. I can't see to the upper end of the bolt. Megane 2 HB 2003, 1.4, 5 doors model. What went wrong?

The car is otherwise ok, but it doesn't pass the inspection because of the missing bolt. How do I fix this?

[vanmanpaul83]

How easy was it to remove the bolt? Is it possible you've completely stripped the threads in the chassis? Are you sure the bolt you are using is the correct bolt? They are real long bolts.These subframes can be completely removed and then jacked up into position and the bolts are long enough to start the threads whilst supporting subframe. The bolts then pull the subframe correctly into position due to the dowell type design of the Bush. If in doubt put a jack under subframe and remove the other subframe bolt and compare the bolt size. There is a support plate that goes over the subframe bush with two more bolts each side.

[DougM]

My understanding of this is there should be a captive nut at the other end. Other forums discuss putting a spanner on the other end to hold it still.