Club 80-90 Forums

Not T25 related but.

I have a seat Toledo (51 plate) with a 1.9 tdi engine fitted. Its been a proper pain in the a*** but for the past year its behaved itself.

This evening however after parking it for a few mins, I restarted it and it knocked and didn't fire up. I tried again and all was well.

I drove home and tried again. ok . I switched it on and off a few times and once it made the nasty knocking noise.

It sounds like a piston hitting a valve but it has had new hydraulic tappets fitted a year or so ago because the valves would stick open and you would lose compression.

Do the bottom pulleys slip on these engines? - but then why would it only do it occasionally? and it drives just fine.

what do you mean by knocking?

big end style knocking or engine going to rip itself out of car knocking

Piston and valve coming together sort of noise. Quite mechanical. Although I really cannot believe it is as its going very well still. I have tried starting and stopping it again a number of times and nothing now. Baffled.

Probably diesel knock.. detonation.
Is oil leaking into the turbo or building ip overnight (blue smoke)
Too much fuel ( grey smoke)
Use any water?

Have you checked/ changed both fuel & air filters?
Is cold start mechanism working right? Staying on too long. Has it any plugin disgnostics ?
Run some injector cleaner through it maybe... ill get you the name of good stuff ibfound on a stall at CamperJam.. magic fuel additive for diesels.