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So I don’t know much about cars, my engine check light has always been on since I bought the car. I took it to a garage to have the diagnostics checked and the mechanic told me that my crankshaft sensor is faulty. The car occasionally doesn’t start. The engine turns over but doesn’t fire up. Does anyone have any suggestions. Thanks

It sounds like the mechanic is on the money. The crankshaft sensor will pop that light on and stop it starting

The unfortunate part is its a pig to change as its located behind the starter motor

Get this replaced, and your problem will go away.

Thank you, I have looked on other forums and some people have also suggested the coolent sensor may also be a problem worth looking at as my EPC light is also on

Coolant sensor wont stop it starting from cold Itll stop it starting when the engine is warm

They are also very prone to failure, so I would look at changing it out. Only use an OEM or a febi part as the cheap copy parts (topran etc) will not last and will fail prematurely.

If the coolant sensor had failed, it wouldve showed on the diagnostics also. It wont hurt to change it, but im almost certain your problem is the crankshaft sensor.

That did also pop up, unfortunately the previous owner filled the radiator with that pink foam stuff which apparently has copper in it and consequently interferes with the sensor so I will change that too. Thank you so much for the advice on parts

Genuine G13 VW coolant - 2x 1.5L bottles, the rest water (ideally distilled) is what you want when you change the coolant

Hi Alex

In your opinion do you need to take the starter motor out or can the sensor be accessed via the air intake manifold, don’t want to start it via the starter motor if it can be replaced by an easier method

Its underneath the starter motor. Theres no access without it removed. Starter motor is only two bolts though and just withdraws

You can do it without removing the intake manifold, which to be fair, is alot more work to remove by comparison.

Access to the crank sensor is awkward though, and its held in with a single hex socket bolt (allen bolt) which is known to seize and round when attempted to be removed

Your mechanic should have the exact error code to point at the fault. Sounds like he has, as Alex says I'd agree with the initial diagnosis.

Take a look at this thread

viewtopic.php?t=62059

Been there, done that, got the T shirt