Hi, I posted a thread a few months ago about why my marea wouldn't start from cold sometimes - it seems that it may be down to the TDC sensor according to my local fiat garage chap! anyone know how easy/hard this is or if you can check if it definitely is this thats causing the problem and also if it's not a DIY job then how much approx does it cost to get it done at a garage!? Cheers in advance, Lindsay

You can check it on a osilliscope (best method) or do a resistance check (probably around 7-850 ohms),never changed one on a marea to be honest but I should think it would be easy enough just a 10mm bolt & from above.

chap at fiat said that you had to use a special tool as there was a critical position for it to work??????????

When you push in the new sensor make sure it is flush & not at a angle then put in the bolt just dont overtighten it,yes the gap is critical but aslong as you fit the correct sensor there will not be a problem.If you want to give me £40 to fit i'll happily do it

Which type is fitted, in the engine block or an external bracket/rotor type?

There is no adjustment on the external type, gap should be between 0.5 and 1.5 mm.

On the internal one measure the depth between housing and rotor tooth, then measure the length of the sensor. The gap between the end of the sensor and the rotor must be between 0.8 and 1.5 mm. This can be tricky without the 'special tool' but if you are careful can be done with a bit of wooden dowel and a pencil.