insignia elite ecoflex 2.0 160bhp - Insignia knock

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Mon 14 Dec 2015 19:53
insignia elite ecoflex 2.0 160bhp - Insignia knock - kenny

I have a 2012 insignia 2.0 diesel with 35k on clock and get knock/pinking/rattle sound when engine is cold and accelerating at around 2000rpm , as soon as temp gauge hits its normal position the knock/pinking/rattle goes, This only seems to show when weather gets colder as during summer its not there, no fault codes or warning lights have ever shown up,

The car is mostly used with shell diesel, engine oil and filter changed recently as it was happening before I changed it. Not done fuel filter yet but next on my list.

could it be glow plugs?

Not sure what else to check after that and no point taking it to a dealer if no codes are showing?

cheddar

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Mon 14 Dec 2015 22:09
insignia elite ecoflex 2.0 160bhp - Insignia knock - craig-pd130

Some diesels do knock noticeably during acceleration in the warming-up phase. My previous Passat PD130 and Mondeo IV TDCI used to do it, and it was worse in winter weather when ambient temps were below about 10C.

The glow plugs are usually still active in warm up, but during warm-up the richer mixture used during acceleration will combust more violently.

If it's predictable when cold and goes when warm, I wouldn't worry about it.

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Thu 17 Dec 2015 12:36
insignia elite ecoflex 2.0 160bhp - Insignia knock - kenny

Just a wee update on this, today before heading to work i disconected the wiring harness for glow plugs and noise is wasnt there, just to be sure it wasn't the warmer temp that we have here today i stopped and reconected the glow plugs and the noise was back. Just tried it again and same result so something in the glow plug circuit is causing it.

Next logical step is to disconect all glow plugs and reconect 1 at a time until noise come back and hopefully find the culprit.

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Thu 17 Dec 2015 18:46
insignia elite ecoflex 2.0 160bhp - Insignia knock - elekie&a/c doctor
Disconnecting the glow plugs does not really prove anything.You need to be careful here,as I think one ore more of the glow plugs incorporates a pressure sensor.Whar equipment has been used to test the system?
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Sun 4 Sep 2016 22:49
insignia elite ecoflex 2.0 160bhp - Insignia knock - gavin gerhold

Cheddar,

Did you get any further with this problem ?

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Mon 5 Sep 2016 10:19
insignia elite ecoflex 2.0 160bhp - Insignia knock - Railroad.

You may have a worn or faulty fuel injector. The purpose of the pre injection phase, prior to the main injection phase is for noise reduction. A good scantool should be able to show the injection phases in respect of the ECM controlling them in graph form, but it cannot show how fuel is actually being injected. For that the injectors will have to be bench tested. Also if the injectors have ever been removed and refitted in a different order than before the operating codes may not be correctly entered into the ECM, meaning the ECM will not have the correct information to correctly operate each injector. This is worth checking.

Glow plugs are also for noise and emission reduction when the engine is cold, but they should switch off after a short while after startup. So if your problem occurs for more than a minute or so after starting a glow plug is not likely to be the cause.

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