1.0L Corsa 1998 pinking - Society Corsa
Hi all,

Got a bit of a pinking problem with my 1.0 Corsa at between 3000-3500 rpm in 4th and 5th gears. I've tried running it on Shell V-Power / BP Ultimate for a few weeks, and even given it a dose of STP System Cleanup. The spark plugs are correctly gapped, new, and look in fine condition. The engine management light has never come on (apart from briefly when starting up) which makes me think the knock sensor is fine... Am I right in thinking that a diagnostic check won't show any faults because the engine management light has never lit?

Don't know if it's related, but the car will often 'hiccup' when setting off after standing in traffic for a while. The fuel and filters are new and the EGR valve was replaced by the previous owner at the last service.

I'm just a poor student who can't stomach the idea of playing with the timing, or even worse paying for someone to look at it. Could the timing chain be poorly tensioned? I'm really struggling for easy solutions and ideas now. A bit of a headache really.

Could anyone help please?
1.0L Corsa 1998 pinking - andwoz
could be your mass air flow sensor,quite common faults
1.0L Corsa 1998 pinking - Collos25
Do you know any of the cars history it could have had a head skim and not used the correct gasget therefore increasing the compression ratio or a may simply be the timing that is out .If you are unsure on how to test it then you will have to use a man that does, you could also be expecting to much of the car and trying to put to much load on it in to high a gear.
1.0L Corsa 1998 pinking - Dynamic Dave
The spark plugs are correctly gapped, new, and look in fine condition.

Are these multi electrode plugs? If so, they are factory preset and no attempt at regapping them should be made.
1.0L Corsa 1998 pinking - Kingpin
What is cold starting like, does it start OK and run fine until fully hot? Sometimes this can give you a clue if it's OK when getting plenty of petrol when warming up but the fault only shows up when it is hot and running lean.
Have you checked for any air leaks in the manifold area, hoses split etc? Not sure if your car still has one of those hot air intake devices to guide warm air into the engine when it is cold but these can cause problems.
I think the timing is set on these, no distributor etc. If the spark plugs are set OK then I would give the ignition HT leads a glance. Eliminate ignition and air leaks before moving on to the fuel system or sensors. From what you say the problems may be caused by a weak mixture or difficulty igniting the mixture when under load or light throttle openings. Besides that as others have said it could be an air flow sensor or even a more fundamental problem with the compression ratio being raised due to cylinder head skim in the past.

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