1989 Isuzu Trooper


#1

I have a 1989 Isuzu Trooper and i was wondering if there is a device on the engine that keeps the engine from starting if there is insufficient oil present. Im wondering if this is the case before i think about replacing the engine. Any info would be greatly appreciated


#2

Never heard of any like that on a porduction car or any kind.


#3

If it has a carburettor, these era carbs have a fuel shut-off solenoid that need to be energized to allow fuel into the carb. If the solenoid goes bad, the truck will not start.


#4

The wiring diagram shows the 2.8L engine circuit has a Backup Fuel Pump Relay which is energized by the oil pressure switch. The Fuel Pump Relay is controlled by the ECM (engine computer). So, I would supposed that if oil pressure fell too low (as from excessive loss of oil) the oil pressure switch would cut power to the Backup F/P Relay and it would cut power to the fuel pump.
It is unwise to defeat the oil pressure switch. It cuts the engine off, by cutting the fuel pump off, to save the engine from a very expensive repair. There is something wrong with the engine if it can’t hold oil pressure. It may be engine bearing wear, or oil pump wear, or low oil level. Fix the smaller problem before it becomes a much bigger problem.


#5

Well, strange but true. The 1973 - 1978 Jaguar XJ6 had an oil pressure cut out switch installed, though I’ve only ever seen 1 car with it still in place - unfortunately I owned the car, which stranded me when the pressure switch failed. Took me an hour to find the problem. That switch was also removed the next day.

That XK block always did burn oil even when new, I guess the reasoning was better to stop the car than blow the engine due to low oil level.


#6

Through about the mid '60s to about 1980 Chrysler wired the oil pressure switchs on all their makes of cars into the ignition system which shut down the engine if the oil pressure got drasticlly low. Isuzu may have adopted a similar system, although Isuzu has had a lot of problems with the Trooper. In fact, Isuzu used to import trucks to North America but they discontinued, rather abandoned, because warranty repairs were too expensive to maintain. I’ve heard a lot of bad news about the Troopers. Things like people not being able to purchase major power train components. I have a co-worker who has spent the last two years finding, and dealing with a new engine and the little things that you end up replaceing after an engine replacement. As a result, he had to buy a new car and the dealership would not take the Trooper as trade.
Get rid of that Trooper while you can.


#7

I heard of other makes having them