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  • [Corsa B 1993-2000] Misfiring when loaded in high gear

    Hi,

    Have a 1996 Corsa Merit 1.2 5door petrol with a timing problem.

    When I go uphill in too high a gear, the 'pinking'/misfiring happens. It increases from nothing as the engine labours. Dropping to a lower gear solves the problem. It happens with new fuel so not a problem of old fuel.

    I was thinking it was due to timing, but I do not understand the way the load makes the timing go out of synchronism. I'm concerned it might get worse.

    Ideas much appreciated.

    Thanks Max.

  • #2
    If you go up hills in too high a gear the engine rpm isn't sufficient to allow the engine to generate the power needed to drive up the hill. The 1996 1.2 is a detuned version of the old Nova engine. On the Nova fitted with a carb it had towards 58-60bhp. The single point injection 1.2 Corsa began life with only 45 horses, and by now several of them will have escaped.

    It is a small detuned engine - it won't climb hills in too high a gear. Drop down and let the engine rev more freely.

    If you don't believe the problem get on a bike and try riding up a hill in top gear. Your muscles will struggle. Then drop down the gears and try again. It's simply physics.
    1972 Viva restoration thread - http://www.thecorsa.co.uk/projects-b....html#post1534

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    • #3
      Originally posted by Taurus View Post
      If you go up hills in too high a gear the engine rpm isn't sufficient to allow the engine to generate the power needed to drive up the hill. The 1996 1.2 is a detuned version of the old Nova engine. On the Nova fitted with a carb it had towards 58-60bhp. The single point injection 1.2 Corsa began life with only 45 horses, and by now several of them will have escaped.

      It is a small detuned engine - it won't climb hills in too high a gear. Drop down and let the engine rev more freely.

      If you don't believe the problem get on a bike and try riding up a hill in top gear. Your muscles will struggle. Then drop down the gears and try again. It's simply physics.
      Hi T.,

      Thanks for reply.

      Yeah, the engine used to not make any noise as it laboured uphill, just t steady loss of power and dropping gear stopped t engine stalling.

      Interesting info. about t Nova engine. Was t engine detuned in connection with lower spec. fuel injection? Why would they lower t hp - to get lower fuel consumption?

      If tuning was done would the hp and fuel consumption be increased by much? And would this mean a 'modified' car and increase the insurance? Or considering the cost, worth it? Thing is, I like my corsa, it's a good wee car for my use.

      I am going to change t oil and filter. I have read that a Mann filter is a good spec., but I have been unable to find out where to buy one. Can u recommend a suitable replacement? I don't think Bosch is good quality, considering the price.

      Again, I appreciate your advice.

      Thanks,
      Max.

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      • #4
        They detuned the carb engine when they went over to injection to meet emissions regulations.

        No point modifying the 1.2 8v engine, just drive it on the limit knowing you really can't break it. Give it regular oil and coolant changes, replace the cam belt and water pump every 40k, and they'll run for ever.

        Mann filters are good - no idea what factors stock them in your neck of the woods though. Just find a good factors and stick with them. You can use Halfords filters in them no problem. The spin on filters aren't as critical as the 16v cartridge type.
        1972 Viva restoration thread - http://www.thecorsa.co.uk/projects-b....html#post1534

        Comment


        • #5
          Corsa 1.2 engine

          Originally posted by Taurus View Post
          They detuned the carb engine when they went over to injection to meet emissions regulations.

          No point modifying the 1.2 8v engine, just drive it on the limit knowing you really can't break it. Give it regular oil and coolant changes, replace the cam belt and water pump every 40k, and they'll run for ever.

          Mann filters are good - no idea what factors stock them in your neck of the woods though. Just find a good factors and stick with them. You can use Halfords filters in them no problem. The spin on filters aren't as critical as the 16v cartridge type.
          Hi T.,

          Thanks again for advice. Sorry for delay in responding.

          Much appreciated.

          Max.

          Comment

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