Please Help: 1996 Geo Prism Dies When Put In Gear

[a little odd]

Thank you in advance for any and all help- I am posting this for a friend.

She has a 1996 Geo Prism that keeps stalling out when put in gear. I have not looked at it myself but it idols fine but sputters and dies when she tries to drive it...

She knows: it has a bad valve - I don't know if bent or stuck or what? but it was driven before with it without problems...

She had a friend suggest it could be bad timing...with a bad valve it sounds like that could be the problem but?

Are there any other things that could be inspected first? How do we diagnose and/or troubleshoot what the problem(s) may be? Thanks !

[Bitter]

if that 'bad valve' has gotten worse she could be running on 3 cylinders not 4, which could cause it to die.

[Kiwi-Corolla]

Have a read of this thread:

any ideas? Car idles, but then dies when put into drive