any diesel experts

[ohwell123]

hi we have a seat leon 07 tdi, at first i though the big end bearing had gone i used to build racing cars so im pretty good with mechanics just looking which road i should venture down

it makes a knocking sound that comes and goes sounds like morse code

however ive noticed the knocking sound only comes when the engine is what i call "hunting" like when a petrol engine runs on 3 plugs instead of 4 and the dashboard vibrates etc this happens when you pull up ie in a car park space

however as as soon as you put your foot down the car pulls fine and then will sound perfect for a while

im having to pay for my dogs heart failure so would be grateful where anyone else would start with this

i can appreciate the glow plugs etc we have no warning lights on the dash


so basically the knockin only comes with this sudden running rough episodes

[Qualified_Survivor]

sounds to me as if you have air in the system or the fuel pump is playing up. Try cleaning the fuel filters then bleed the system.

[ohwell123]

ill take a look it performs and sounds fine when you floor it though?