Hi all

I've removed my tandem pump in order to have greater access to a leaking flange housing. However, after replacing the tandem pump, the car won't start.

I can confirm fuel is being pumped by lift pump and the filter is full of diesel having opened the inlet pipes. However, no fuel is being pumped back by the tandem pump on the return pipe

I've checked the vacuum line on the tandem pump while the engine is turning and there does seem to be a vacuum so the pump is definitely turning.

Also, when replacing the tandem pump, I cleaned the metal gasket but didn't replace it. I'm wondering now if i needed to replace with a new gasket or do I need to bleed the tandem pump somehow? I've hooked it up to VAG and the engine has no fault codes stored and I have tried the recycling the pump by turning the key off and on but really don't know what to try next.

Just to confirm there was no issues with the car starting before I decided to remove the tandem pump... (what was i thinking!!)


Thanks in advance