- Apr 21, 2009
on 1.9tdi, 2002, 110
Thats a very vague description mate. Do you mean that the car is struggling to maintain its idle speed? If its dropping under about 700rpm, the oil light will illuminate to show low oil pressure.on 1.9tdi, 2002, 110
Chain tensioners in Saab and Nissan engines fail regularly, they are 2 examples from personal experience which can allow the chain to slip over the teeth or in the worst case, to jump the sprockets altogether.Chain drives Do Not Slip. They can fail, if one part seizes and the teeth get stripped off the cogwheels, but that isn't slip. Even less likely, the tensioner could have failed allowing the chain to disengage from the sprockets, but again that isn't slip in the loss-of-friction sense. Chain drives don't rely on friction, but on mechanical engagement of the chain roller with the sprocket teeth. Very efficient too.
Low oil pressure is not a good sign, and would have me walking away too. Rattle on startup is another sign of poor oil circulation. It may be as simple as a blocked oil filter, but if it hasn't been spotted and corrrected already, I'd worry about what else might have been left undone on the car.