Re: 87 4KQ engine problems - fixed!

["Craig Parkin" <cparkin@telusplanet.net>]

Thanks to all those who responded to my rough-idle problem. The fault
was in the coolant temp. sensor and not the OXS sensor after all. The
temp. sensor was an open-circuit with the engine cold (20 deg. C). I
guess the fuel-injection system thought it was sub-zero, making the
mixture very rich. The system must not be smart enough to be able to
tell that the sensor has failed and put the mixture setting somewhere in
the middle of the range. A replacement sensor measured about 2700 ohms
with the engine cold.

Craig Parkin
1987 4KQ 236,000km
black with no more black clouds trailing