Alfa 156 Selespeed jumping when temp clock reads over 90oc

[Paul 5]

I own a 2000 156 Selespeed with 76k kms, annually serviced and cam belt changes every 3 years.

65k km service June 2011 - Alfa recognised service and mechanic told me not to fill with petrol as petrol was going off and causing car to be sluggish. He recommended changing the spark plugs to help it heat up quicker ($800 job), said I'd think about it.

72k km service in March 2012 - i took it to another garage and he said the spark plugs would easlly see 80 to 100k kms. He said the last service did not change the coolant or filters properly. Told me to take it on a long good run and i did about 3 weeks later. However since this service, in traffic the car heats up very quikcly and when the temperature gauge goes over 90oc it bucks and jumps when it takes off from stop position. It can be quite dangerous especially if in a long traffic jam. However if cars then gets about 60km p/hr the temperature drops back down and its fine again. I thoutgh it would go away but its not and I'd like to know some idea whats wrong before i return to the mechanic, i can't afford another major service atm.

[colcol]

Where do i start?, Petrol does go off, but only after it has been in tank over 6 months, without driving, if it has gone off, then take it for a big drive and almost run it dry, and fill up with good branded petrol, Caltex, Mobil or Shell, no cut price rubbish, as you only get what you pay for, Have a look on ebay for 8 twin spark spark plugs, or look at EB Spares or Alfa Workshop in the UK, should be $150 delivered???, and an half hour to fit them, unless the plugs are fouling up, stick with the standard heat range, they should last at least 100,000klms, as all the fuel is unleaded and doesn't foul plugs, the last service, the filters were not changed properly???, what they are the wrong filters, wrong brand, put in backwards??, please explain what you mean by this, the coolant is usually Red or Pink in color, and if it has rust in it, then have it flushed and changed to a brand name ie PARAFLU, NULON, REPCO etc coolant, if it is running too hot, have the thermostat checked, as it is a problem area on twin sparks, the Selespeed needs hooking up to an Alfa Examiner to see what the issue is with the Selespeed, this is for an Alfa Service Provider only, you may have a dud sensor or a sensor that needs re-setting, or the Selespeed may need recaliberating, [an annual job], Colin.

[AGM155]

Also worth checking the water pump - just before I had the belts done on my JTS I noticed it getting a bit hot and rough in traffic. When the belt (and water pump) change was carried out I was told it had not been done the last time (this was prior to my ownership) and that the pump was on its last legs. Since the replacement water pump I have not noticed any further temperature issues. Having said that armchair diagnosis is one thing - I think your best avenue is to take the car to a respected dealership or specialist and get a proper diagnosis from someone who knows the cars.

[colcol]

Spot on AGM156, the water pump should be changed every second cam belt change, that is 6 years or 100,000kls, they are not that expensive, mine was a brand name, $84, when you change the cambelt, the water pump is sitting there looking at you, an extra half an hours work to change, while you are doing the cam belt, as it is a pulley for the cam belt, if the water pump seizes or starts leaking, its curtains for the cam belt and about a second later for your engine, i have not heard of the water pumps not pumping properly when they get old, they usually leak and get noisy, Colin.

[Paul 5]

Thanks guys, that has been really useful. I am taking her in next week to have it sorted.