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m40 rough running

Posted: Sun Feb 01, 2015 10:04 pm
by Ash318i
So I have an M40 engine which starts perfectly when cold or warm, no problems. The only problem when cold is maneuvering, the car is hardly responsive to the throttle and stalls very easily. Any help would be appreciated.

Re: m40 rough running

Posted: Thu Feb 05, 2015 1:58 am
by Ash318i
Does anybody have any ideas?

Re: m40 rough running

Posted: Thu Feb 05, 2015 6:28 am
by sweep
Cold start device ?

Re: m40 rough running

Posted: Thu Feb 05, 2015 6:33 am
by TPS
Does the TPS click?

Re: m40 rough running

Posted: Thu Feb 05, 2015 4:30 pm
by Ash318i
yea I can hear it click when I move the throttle from idle. I dont know if it has any cold start system.

Re: m40 rough running

Posted: Sat Feb 07, 2015 11:09 pm
by aze30
air leak is what id be first searching for....one of the breather pipes on my car was perished and cracked allowing unmetered air into the inatke causing very rough running and stalling at times.
the breather pipe from the idle control valve was perished as was the one from the cam cover to the inlet throttle body...after replacing these the car runs superbly!

get some carb cleanr and spray it around the hoses to see if you hear an increase in the engine speed while its ticking over on idle

Azzy

Re: m40 rough running

Posted: Sat Feb 07, 2015 11:14 pm
by magpie
idle control valve or a split inlet trunk that runs from throttle body to AFM [ air flow meter ] .

remove this trunking and check the underside for cracks/splits .

Re: m40 rough running

Posted: Sun Feb 08, 2015 2:12 am
by Ash318i
Ill try all of these, thanks guys