Alfa Romeo Owners Club of Australia Forum

Technical => 160 Series (90, 75, 164 Sedans) => Topic started by: supervanawesome on May 08, 2015, 09:43:28 PM

Title: 75 twin spark runs rough when cold
Post by: supervanawesome on May 08, 2015, 09:43:28 PM
My 75 2.0 tspark seems to be grumpy when started from cold. Will usually cut out unless i keep the revs up for around 30 seconds and will hestitate and loose power for the first few minutes of driving. All new plugs and ignition , no obvious vacume leaks and have cleaned idle control valve. Idles and drives good once warmed up. Has anyone else had this issue?
Title: Re: 75 twin spark runs rough when cold
Post by: Duk on May 09, 2015, 08:57:54 AM
Check the coolant temperature sensor for the ECU. Make sure it plugged in and that the pins in the plug are actually attached to the wires.
Title: Re: 75 twin spark runs rough when cold
Post by: GTVeloce on May 09, 2015, 05:24:05 PM
As Duk said, check the temp sensor. It is awkward to get at being buried underneath the no. 4 inlet manifold and above the starter motor but if you remove the AFM and black concertina piece you should be able to get a multimeter onto the pins of the senor where you can check the resistance and cross reference it to a suitable chart (ohms v temp) like found here;
http://www.hiperformancestore.com/Motronic.htm
See section 7. I have found a proper chart somewhere but can't remember where.