Vauxhall Astra G Petrol - 2003 Vauxhall Astra Cutting Out

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Wed 9 Sep 2015 11:03
Vauxhall Astra G Petrol - 2003 Vauxhall Astra Cutting Out - OllieZ

Hello,

I have a 2003 Vauxhall Astra 1.6 Petrol Elegance. For the last few months it has been suffering with an intermittent problem which nobody can get to the bottom of. The car is low mileage and starts fine every day. When warm it will start to 'judder' and lurch, this resolves after a few minutes if you keep your foot pressed on the accelerator. However, if you need to stop or press the clutch in, the engine will not idle and it will stall. After a couple of minutes the engine will start up again and will run and idle fine. The problem will then repeat in another 30 mins time!!

The car has been seen by two local garages who are unable to find the fault (both cleaned the throttle body with no improvement), I have also taken it to Vauxhall who said that no fault codes were being displayed - and they also cleaned the throttle body!! I have also ran a full tank of petrol with Fuel Injector Cleaner through to see if this helps - it didn't! It has also had a recent service which didn't make the problem go away.

Someone suggested that the EGR valve could be sticking open but the Vauxhall garage dismissed this as no EGR fault code was being displayed. Can you think of anything else to try? The car is otherwise in good condition and I am hoping to find a fix!!

Many Thanks

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Wed 9 Sep 2015 13:22
Vauxhall Astra G Petrol - 2003 Vauxhall Astra Cutting Out - hardway

If you'd come in to mewith that description my first thought would be a fault with the coolant temperature sensor,

And I realise the cars been code read but a CTS changes voltage output depending on coolant temperature,

It has a high resitance at say 10 degrees and much lower at say 70 degrees.

so cold resistance of 4000 ohms and the ECU "puts the choke on"

hot is around 200 ohms and "the choke is off"

Now ANY restance reading inside these values and THERE WILL BE NO FAULT CODE.

But if a faulty CTS reads anywhere near 4000 ohms when the engine is hot you'll get pretty much exactly your symptoms.

Reading live data on a scanner will tell if the CTS is suddenly making a big fluctuation

So CTS or wiring/connectors is my thought.

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Wed 9 Sep 2015 13:22
Vauxhall Astra G Petrol - 2003 Vauxhall Astra Cutting Out - Peter.N.

Air leak on the inlet manifold?

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