corsa 1.2 choke

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Thu 17 Oct 2002 23:54
corsa 1.2 choke - needhelp
I have a corsa 1.2 8v and the fuel economy is raher bad only about 30 mpg. However The hot air feed from the exhaust manifold goes nowhere into the air box it only has the cold air feed. If I was to drill a hole into the airbox to take the hot air feed this would allow the engine to warm up quicker yes???? But would this cause me any problems when the engine has reached operating temp. The automatic choke stays on for a long time due to no warm air entering the engine and I assume this is causing bad fuel economy.......
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Fri 18 Oct 2002 12:51
corsa 1.2 choke - John S
needhelp

There should be a hose from the exhaust manifold heatshield running to the air filter box on your car. There is no need to start drilling holes in the airbox - either reconnect the hose that's there, or buy a new hose!

I don't believe it will make much difference to the warm up time though, as this hot air feed is primarily intended to improve the vapourisation of fuel during cold starts.

If the car is taking a while to warm up, then the problem could be the coolant thermostat. When I had one of these it seemed to warm up reasonably quickly and soon dropped off the fast idle. Fuel economy depends very much on useage, but I don't believe we ever got below about 34 on a tankful, even with a lot of short runs.



Regards

John S
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Fri 18 Oct 2002 21:10
corsa 1.2 choke - Andrew Moorey (Tune-Up)
Corsa is fuel injected and so does not have the warm air facility.As John S says, check T/Stat function, should be up to 90+ reasonably quickly if temp loiters around the 50 mark that is where the juice is going. Also what method do you use for calculating mpg, please don't say "well a tenners worth goes from here to here on the gauge........" Brim the tank, run a good distance and brim the tank again at the same pump. Remember that generally speaking cars will use more fuel in cooler conditions. Also take into account the type of driving you do and the length of journey.
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Fri 18 Oct 2002 23:22
corsa 1.2 choke - needhelp
i have a journey of 15 miles to work every morning and on a full tank of fuel as in totally full I can get 330 miles to a tank before the petrol light comes on. I don't drive the car hard and most of the journey is dual carriageway. Only really drive at about the 50-60mph mark.

The weather is rather cold at the min and it can take the best part of 10mins or more before the temp hits 90. Its had a major service recently I did this myself so I know evrything else is fine. Thermostat seems to be a good idea though. I'll check it this weekend and get beck to you.

Thanks very much for your input


matt
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