The very bottom of the front, passenger-side suspension coil spring on my 97 Saab 900 has broke. It is piece of coil that rests on the metal guard that supports the coil. The car doesn’t seem unstable when driving. Is this an urgent repair? And can a mechanic replace just the coil or does the whole suspension need replacing when the coil spring is replaced?
This is a repair that should be replaced as soon as possible. If the coil spring decides to spin on the strut, which can happen now that the bottom part is broken, it can spin right out of the strut assembly and cut into your tire. I have seen it happen before. Some people drive for months or years on a broken spring; others end up cutting a tire as soon as it happens. I wouldn’t risk it for too long.
To replace the spring, you can either replace a pair of springs by themselves (they are sold in pairs, and if you install only one new spring, the car will probably lean and handle strangely), you could replace a pair of strut assemblies with springs, mounts, etc (many companies sell preassembled struts, such as Monroe’s Quick Strut), or you could purchase a used strut assembly from a salvage yard. The “whole suspension” does not need to be replaced.
Like mark9207 said. I would just emphasize that whatever you do to one side must be done on the other at the same time.
You have to fix it. The spring will break again. Yes, it did on a 65 Ford Fairlane which had a misdesigned front suspension but if it breaks once…