How old is the petrol in the tank?
Petrol goes off after 6 months to a year.
The thing which looks like a fuel filter near the fuel pump underneath the car is the accumulator, it holds the fuel pressure in the injection system to help with hot starting.
Main fuel pump and accumulatorhttp://www.ebay.co.uk/itm/mk1-golf-gti- ... Sw~epZgj44
Accumulator http://www.ebay.co.uk/itm/BOSCH-Fuel-In ... Swo6lWF6Ey
Sorry for the eBay links but can post up pictures now photobucket wants silly money to host pics.
The car will run if the accumulator is faulty you will just have problems starting the car when it's hot till the fuel pressure increases so will take more cranking to start, when cold the 5th injector and warm up valve will add more petrol.
The filter in the engine bay is the main filter which should be changed and it should be under pressure if you loosen the connections to it so watch out for spraying petrol and have a cloth handy to catch the petrol and don't tip the filter as it should be full of petrol.
Every 2 years or 20,000 miles is when you should replace the main fuel filter.
There is a filter/gauze on the end of the lift fuel pump inside the fuel tank and another filter/gauze in the fuel line going into the fuel pump underneath the car and that's it for filters, these 2 filter/gauzes do not need replacing unless damaged and can be cleaned.
I would check inside the fuel for rust etc buy removing the lift pump and fuel gauge sender (access via the hole underneath the back seat) if still not starting or lack of fuel at the engine.
Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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