1993 1.2 Engine smoke - petervm
Hallo
Twingo 1.2L (Renault R4 engine) 1993

The car has done only 40,000 miles. It is in mint condition. The engine works perfectly well, but recently acidy fumes started to come from around the air filter, but not (!) from the exhaust. This happens when the engine has warmed up, but it does not seem to effect the working of the motor.
What can cause this and what repair is needed?
Many thanks for your help.
Petervm
1993 1.2 Engine smoke - Screwloose

Are these exhaust fumes, or oily smoke from the crankcase?
1993 1.2 Engine smoke - petervm
Hard to tell, but I do not think that it is exhaust smoke. More like heated or burned oil from crankcase, due to broken piston rings (although this would also provide evidence in the exhaust system) or blocked intake pipe return.
There is no smoke coming from oil filler when cup is removed.
1993 1.2 Engine smoke - Screwloose
Could it be oil dripping on to the exhaust manifold?

Edited by Screwloose on 16/11/2008 at 17:35

1993 1.2 Engine smoke - petervm
Definitely no. The smoke comes from either side of the air filter housing where the cover does not fir properly. It is also visible when driving the car or it can be smellt from the air intake. The amount of smoke is quite considerable, but so far no loss of oil is visible.
1993 1.2 Engine smoke - Screwloose

If this is piston blow-by from a breather hose; when and how did it start? Have you had a search with a torch to see where it originates?
1993 1.2 Engine smoke - petervm
Having examined the engine in more detail, and having driven the car, it became clear that the smoke was not oil based but a water/coolant mixture. As the water level in the radiator dropped, it appears that the head gasket is blown. We are going to look at the breather hose as well, but I am now quite sure that the culprit is the head gasket.
Many thanks for your help.
Petervm

 

Value my car