M20 320i idling problem!

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patrick320i
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Sat Jan 26, 2013 1:18 pm

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! :D
will post some pictures soon
its a 1983 320i pre-facelift :)
Silverfang
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Sat Jan 26, 2013 2:06 pm

I'd check the following and possibly replace.

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

Check crank position sensor
BMW and Opel, both RWD, both german, both good fun
http://www.clockservicing.co.uk/ For any clock repairs try here.
jimmyspeed
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Sat Jan 26, 2013 2:06 pm

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
abelai
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Sun Jan 27, 2013 11:14 am

Also check tps is working otherwise dme won't know you want to idle
If I can't fix it I'll f**k it up so bad nobody can!!
Grrrmachine
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Sun Jan 27, 2013 11:42 am

Air slide valve and associated plumbing would be my guess:

http://www.e30zone.net/e30zonewiki/inde ... lide_Valve
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patrick320i
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Sun Jan 27, 2013 11:42 am

will try a couple of these try and see whats wrong with the engine..... thanks a lot for the info :)
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Brianmoooore
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Sun Jan 27, 2013 9:08 pm

Grrrmachine wrote:Air slide valve and associated plumbing would be my guess:

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