Scenario:

Racing along having a blast. Round the bend just before the pits on the KY oval and a car pulls out sideways in the track. Collision occurs throwing me into a pit stall wrecking the car and giving me a stop an go. I can creep to a pit box but the car is not repaired. It goes into pit stop mode but only lasts a second or two and says pit over..... Is this a bug or is it supposed to be like this? In reality a car with this much damage would surely be out of the race but if I had landed just outside of the pit entrance my car would have been repaired when going to the pit box.

Sorry if this has been addressed before.

Its because you were serving your stop and go penalty, most probably. You'd have to leave the pits, and do another lap before you could pit.

IIRC it is part of the penalty that you are not allowed to repeir or refuel. Or else you could just adjust the pit strategy accordingly and no harm would be done.

but it's still a problem, because you should have to chose if you want to do your penalty stop or a repair stop.
You should be able to tell LFS that you want to do a normal pitstop the next time you pit. of course you would have to do your penalty stop later.

Because a lap on Aston GP can be very long with a damaged car

Quote from ColeusRattus :

IIRC it is part of the penalty that you are not allowed to repeir or refuel. Or else you could just adjust the pit strategy accordingly and no harm would be done.

This is true, but it would be better letting him do his normal pitstop. He would have to complete his penalty after that lap. It is really a security issue to force a damaged car around the track once more.

So normal pitstops should be doable, even if a penalty is pending.

As suggested, you should be able to choose if you want to do the pit-stop or the stop&go, this is very important if you don't have enough fuel to do another lap.