Patrick Gallant

Hello,

I have just pulled the exhaust manifold off my 88 Civic, 1.5 litre, dual
point injection. I had a look inside the exhaust chambers and noticed
something strange, the exhaust valves on #2 and 3 were normal looking, dark
black with a bit of carbon build up. The exhaust valves on #1 and 4 are as
white as snow!!!! I thought maybe injector trouble, burning to lean, but
this would affect all cylinders equally. I tested the resistance on both
injectors and they are within the limits specified by Honda. Any
suggestions of what else might be causing this??

Thanks
Patrick

Eric

Patrick Gallant wrote:
>
> Hello,
>
> I have just pulled the exhaust manifold off my 88 Civic, 1.5 litre, dual
> point injection. I had a look inside the exhaust chambers and noticed
> something strange, the exhaust valves on #2 and 3 were normal looking,
> dark black with a bit of carbon build up. The exhaust valves on #1 and 4
> are as white as snow!!!! I thought maybe injector trouble, burning to
> lean, but this would affect all cylinders equally. I tested the
> resistance on both injectors and they are within the limits specified by
> Honda. Any suggestions of what else might be causing this??
>

One of the things that comes to mind is that it could possibly be
antifreeze. I head gasket problem doesn't seem to likely since one would
expect that to show up on paired cylinders, e.g., 1 & 2, not 1 & 4.
However, it could be that there's another source for antifreeze getting into
the engine such as a pinhole leak in the water jacket of the intake
manifold. I had this happen to me on an older Honda. Inspection of the
intake manifold revealed a streak of dried white antifreeze running down the
inside of one of the intake runners. Pressure testing it showed that there
were air bubbles coming out. I had good luck with a used manifold from a
wrecking yard but your mileage may vary.

Eric