E30 Zone

hi there, i've recently baught an e30 as a project cause it still needs a lot of work when i baught it it ran just fine and had no issues whatsoever but now its giving me problems.... it starts at first time but it then automatically revs to about 3,000 on its own and then the revs fall till it stalls and does the same thing everytime i try starting it..... anyone got any idea what the problem is ?

in the meantime i'm getting it free of rust!
will post some pictures soon
its a 1983 320i pre-facelift

I'd check the following and possibly replace.

Blue temp sensor - replace (£5~)
Clean and check idle control valve.

Check crank position sensor

a good start is to check for perished hoses and vacuum leaks, there are so many vacuum operated systems on the earlier cars

- spray some brake/carb cleaner around the hoses/gaskets when its running if theres a leak the idle should rise

Also check tps is working otherwise dme won't know you want to idle

Air slide valve and associated plumbing would be my guess:

http://www.e30zone.net/e30zonewiki/inde ... lide_Valve

will try a couple of these try and see whats wrong with the engine..... thanks a lot for the info