Re: [DML] idle problems

[Martin Gutkowski <martin@xxxxxxxxxxxxxx>]

Warren Wallingford wrote:

> there is a temp sensor that tells the ECU to let more air in when the engine is cold-the Contant Idle Switch or Thermister.  These go bad in a characteristic way.  The engine will idle fine until it warms up, then as the engine warms, will rev higher until it settles into a 2000-2500 rpm idle.  The thermister is located in the coolant distrubution pipe under the intake manifold.  It cannot be unplugged or overridden exept by disabling the ECU.  This failure is very irritating.
>  
>
Yes because it's such a sod to get at :-)

Just to add, these invariably fail open-circuit (and sometimes the 
connector can go bad resulting in the same symptoms) but is incredibly 
easy to diagnose. If you look at the top of your idlespeed ECU, you'll 
see that the pin-out for the plugs is numbered. Look for pins 9 and 11, 
and put an ohm-meter across them in the plug. From memory, the reading 
should be between 700 and 2200 ohm depending on engine temp. If it's O/C 
you immediately know where to look.

Martin





To address comments privately to the moderating team, please address:
moderators@xxxxxxxxxxx

For more info on the list, tech articles, cars for sale see www.dmcnews.com

To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/dmcnews/

<*> To unsubscribe from this group, send an email to:
    dmcnews-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/