The thermostat for the 3.5 Liter is under a flange bolted to the top of the block (in the valley), connected to it is a black pipe that connects to the lower radiator hose. This flange has four bolts that are accessed only after removing the intake manifold. Removing the housing that connects to the upper radiator housing optional.
Its under the intake
I would start by checking the thermostat, it may not be opening.
1999 Isuzu trooper
Radio antennae are located in the rear side windows.
The sister vehicle of the Isuzu Trooper is the Acura SLX
Under the intake manifold, its very difficult!
In the fuel tank
the thermostat for this engine is located at the top front of the engine under the elbo that conects the hose to the top tank
blown fuse?
how to set the timing on 3.5 liter engine on a trooper 98
ATF-III
I believe that it's just above the Front Right spark plug coil. It has a vacuum hose attached to it.