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Corsa B 1.2 startup behaviour

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  • [Corsa B 1993-2000] Corsa B 1.2 startup behaviour

    Engine starts OK, runs for a minute or two,-then stalls. Restarts OK but revs up for a few seconds and then returns to normal idle. Engine can idle for ages after this with no problems. Usually occurs when temp is below freezing. -Any ideas on what causes this behaviour?

  • #2
    Sounds like a sticky idle control valve and/or throttle body. Try cleaning them with some carb cleaner.
    1972 Viva restoration thread - http://www.thecorsa.co.uk/projects-b....html#post1534

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    • #3
      There's a chance that I may do that before the weekend before the real cold sets in. February here can present temps down to minus 50 centigrades. Not much fun fixing cars outside under such conditions. Need to buy an electric coolant heater as well. We had minus 38 for a couple of days and the corsa refused to start when I was going home from work. Had to let it sit in the parking lot til the temps started rising enough to get it going again. In february that would mean until spring :-)

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      • #4
        Guess you're not in the UK then?
        1972 Viva restoration thread - http://www.thecorsa.co.uk/projects-b....html#post1534

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        • #5
          Northern Norway, three hour drive away from bloody Siberia.

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          • #6
            Ah - somewhat cooler than the usual temperatures the Corsa was designed to run at. One consolation is that you probably get to see the Northern Lights, something I've always wanted to see.
            1972 Viva restoration thread - http://www.thecorsa.co.uk/projects-b....html#post1534

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            • #7
              Yes, I get to see the northern lights,-lovely sight and well worth a trip.
              The Corsa is fine in these temps provided a coolant heater is installed. Either a 500 watt heater element in the engine block or a 1000 watt heater+pump in one of the radiator hoses. It is a bit cold when taking it for short trips but fine on longer distances. My Corsa has no coolant heater and the coolant is a bit too diluted so it starts to become slushy at about -20 deg. C.
              I planned on replacing the coolant today with a more contentrated mix since the temps rose to a mere -7 deg. and guess what, it was -30 again this morning.
              Despite that it did in fact start, so I tried to unhook one of the hoses from the radiator but gave up. Cold rubber and aluminium and brute force isn't a good idea, but I did manage to apply a bit of pressure to the hose after the clip was loosened,-enough to leak out a pint of coolant which I replaced with concentrated clycol.
              Problem now seems to be air in the system which seems to hinder the flow of coolant because the engine gets up to well over 95 deg. in a real hurry while the blower inside the compartment blows icy cold air. Where's the best point to get the air out? The coolant temp sensor? Tried to locate it but no luck.

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              • #8
                The 16v engines are virtually impossible to bleed - the only real solution is to drain the system and refill really slowly - but I guess that's not something you'd want to do with your current weather conditions. When you refill these engines you need to do it at the smallest trickle to avoid airlocks.

                There are two coolant temperature sensors on the B version of the 1.2 16v engine. The one for the temperature gauge is on the EGR housing top right of the engine block as you look into the engine bay. It is a small bolt in item (about 11mm from memory) with a single wire running to it. The other one is the Coolant Temperature Sensor for the ECU, which tells the ECU when the engine warms up so it knows to lean out the fuel/air mix. That's on the water pump housing on the left hand side of the engine. Neither usually allow the system to bleed due to the design of the engine cooling system.

                One trick which sometimes works is to park the car on a steep slope facing downhill, the idea being that it encourages air to move from the block to the header tank, run the engine with the cap off the tank and keep squeezing the big pipes running to the radiator. Be careful because with an airlock the engine fan can come on very quickly and without warning so keep hands and clothes well clear of it.

                The best way to add concentrated antifreeze to the system without undoing any pipes or causing any chance of an airlock is to siphon the contents of the header tank out and then replace with neat antifreeze. Do that a few times and you'll get fresh neat antifreeze into the system very easily.
                1972 Viva restoration thread - http://www.thecorsa.co.uk/projects-b....html#post1534

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                • #9
                  If you are topping up to increase the strength of your antifreeze be sure to use a full strength one.Many are already pre diluted to equal what is normally used when the car leaves the factory.This gives protection down to minus 36,but only if no water has ever been added to the system. In norway you will need at least this much protection,if not more with windchill. If for instance you have one part 'minus 36' antifreeze to two parts water you will only get protection down to minus 18, nowhere near enough, even in the uk. I would drain down and start with fresh antifreeze. The full strength stuff is much stronger, about minus 60 I think,but I'm not sure.

                  Incidentally,changing subject from engine coolant to screenwash , for your climate its worth being aware that winter screenwash does not always give good value when diluted. If you mix a litre of minus 60 windscreen wash with a litre of water you dont get two litres of minus 30. Its only good for about minus 24
                  Last edited by Bugman; 11-01-2015, 10:44 AM.

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                  • #10
                    Minus 40. I'm in no hurry messing with the car today. I've seen what minus 20 does to 0W40 oil, it runs real slow. Minus 40 will make it next to solid.
                    Starting an engine now is begging for disaster. My old Mazda 323 on the other hand fired right up in minus 42 with the choke mechanism not even working, but the Corsa is the wife's car so I'm not about to start WW3 anytime soon :-)

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                    • #11
                      wow,thats cold. But bear in mind if your antifreeze is not up to strength you can seriously damage the engine,radiator etc without even using the car unless its on a heater.

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                      • #12
                        Originally posted by Bugman View Post
                        wow,thats cold. But bear in mind if your antifreeze is not up to strength you can seriously damage the engine,radiator etc without even using the car unless its on a heater.

                        I've never seen antifreeze+water freeze solid as pure water does. Instead it becomes slushy and the slush gets thicker the colder it gets. Also I've heard that antifreeze contracts with low temps instead of expanding. That said,-it's still a bad idea to start a car in very low temps when the antifreeze has become slushy. It seems that the water pump just digs a cavity in the slush but can't seem to move it in order to create circulation through the cooling system. If the temps are moderatly cold the engine manages to heat up the rest of the system by conduction quite fast. In extreme cold temps on the other hand the coolant inside the engine block will not be able to heat up the radiator+hoses before a long time has passed. -Long enough time to cause the engine to overheat. When the system finally warms up the over-heated engine will get a good dose of freezing cold coolant. A nice way to get a cracked engine.

                        In fact,-the car does have a heater. Found that out after taking a better look than last time. But, the engine acts differently when on the heater. It seems to "hold back" a bit on low revs. Could it be that the ECU gets a bit confused by the slightly heated coolant before the engine is fully warm. Never experienced this behaviour when starting from a cold engine.

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                        • #13
                          The ECU determines the fuel/air mix by measuring the coolant temperature - so yes - if you pre-heat the coolant it'll fool the ECU into leaning out the mix too soon.
                          1972 Viva restoration thread - http://www.thecorsa.co.uk/projects-b....html#post1534

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                          • #14
                            You seem to be aware of the risks of running a slush puppy cooled car!
                            Full strength coolant antifreeze gives protection down to minus 80, but you shouldnt use it neat.For your climate the optimum strength is 70% antifreeze 30% water, which gives protection down to minus 64C.
                            For the information of those in the uk ,here the 'standard' 50/50 mix is best,giving protection down to minus 37C. Its often sold slightly cheaper already diluted .Even this might give a dilution chart,but personally I wouldnt dilute much further, especially up 't' north.

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                            • #15
                              Originally posted by Taurus View Post
                              The ECU determines the fuel/air mix by measuring the coolant temperature - so yes - if you pre-heat the coolant it'll fool the ECU into leaning out the mix too soon.
                              It is when the revs are low and I'm trying to accellerate too fast that it happens. Lean mix seems like the cause. When starting from freezing cold the smell of gas can be noticed a mile away. It's obvious that the ECU gives the engine plenty of juice under those circumstances, but when pre-heated no smell of gas.
                              -Oh,- b.t.w. the stumbling that I complained about on this forum all summer has stopped as soon as the temps got low in the winter. Perhaps it'll return when the temps rise again. My hope is that the car stops permanently one day so I can find the culprit.

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