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Ross , Diagnostic and repair technician
Category: UK Car
Satisfied Customers: 1158
Experience:  Licensed diagnostic and repair technician
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Astra 2005, 1.7dti 100ps. Recently began to refuse to start when hot.

Resolved Question:

Astra 2005, 1.7dti 100ps. Recently began to refuse to start when hot. Five min of cooling down it would go. This period has grown to over 30 min. Now also stumbles occasionally under load and has cut out at low revs and won't restart until cool. No warning lights coming on.
Submitted: 3 years ago.
Category: UK Car
Expert:  Walt-Mod replied 3 years ago.
Hi,

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Expert:  Greg replied 3 years ago.
Name isXXXXX goal is to provide you with excellent service – if you feel you have gotten anything less, please reply back,

This is a known issue with the Crank shaft sensor ,

What you will have to do is check and see if you are getting spark to the plugs when you have a no start situation .

Also check and see if you are getting fuel to the cylinders ,this you can check with a can of start helper , when you have a no start spray the start helper down the throttle body
at the same time as trying to start ,
If the engine starts then you are losing fuel delivery which would point towards a malfunctioning fuel pump that is shorting out when hot, when cools down will work again until hot.may notice this happen more often with a low tank of petrol ,if this is the case replace the fuel pump .

If the engine does not start with the start helper then have the crank sensor checked .

Need further assistance then please get back to me with the reply box below.

Kindest regards Greg
Customer: replied 3 years ago.

It's a diesel!

Expert:  Greg replied 3 years ago.
Hi .

Sorry will have to opt out and put you onto another expert that has experience with this car of yours ,please wait someone will be along if they are on line ,may take an Hr or two .

Rgds Greg
Expert:  Ross replied 3 years ago.
Hi, welcome to Just answer! My name is XXXXX XXXXX i will help with your question

Greg mentioned the crankshaft position sensor, this was a known fault on the petrol models, however it is also a common problem i see on the diesel models on a regular basis. The sensor is used to tell the injectors when to inject, so without this signal the engine will cut out, the fact you say it happens when hot is classic of the crank sensor, its also one of the very few sensors that will NOT cause the engine management light to come on, they tend to fail as the get hot, once cooled down, they start working as normal, part of its normal operation is to give no signal (ignition on but engine off) so the engine management knows no different, hence no warning lights.

With no fault codes these problems are difficult to diagnose, but from my experience the crank sensor is nearly always the cause of this, so will definitely be the first place to look, and being relatively cheap and simple to replace, its probably cheaper than going for in-depth diagnostics to tell you the same thing.

I hope I’ve provided the information you were seeking. If you are happy with my service, please provide a rating. If not, please let me know so l can continue to help you. Thank you, Ross.
Ross, Diagnostic and repair technician
Category: UK Car
Satisfied Customers: 1158
Experience: Licensed diagnostic and repair technician
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