I am having a problem with a set of seats I am trying to put in my 87 Iroc.The seat back latch will work fine with the seat on the floor of my garage.But when I put the seat in the car the seat back will not lock into position.I don't know what year the seats are out of.I thought all third gens were pretty much the same.Thanks for any help,Steve

 

There is information out there that says that the seats aren't designed to lock unless they're tilted at a certain angle OR there is a sudden change in inertia of the vehicle they're installed in (inertia lock similar to the seatbelts).

What I did to make my seat (only one, haven't done the other) so that the back will only come forward if the lever is pulled (you know, like just about every other car on the road) was to simply pull up on the upholstery and install a screw and spring against the inertia lock lever. No problem since.

 

Thanks Maverick.sounds like a good fix.

 

There are 2 issues with the spring fix...

1. It's pretty difficult to see inside the seat back mechanism.
2. It's best done with the upholstery off. I didn't (and still don't) care about the upholstery on the seats since it's damaged. You will hear ripping. The upholstery needs to be pulled up over the mechanism almost all of the way to get to where you need to drill the hole for the screw that will hold the bottom of the spring that will push against the inertia lock.