20 Most Recent 1993 Isuzu Trooper - Page 6 Questions & Answers

the voltage is normal, did you check the voltage at the dash or at the sensor? you should have the same voltage at the dash if you do then replace the spedo unit, also does the odometer work? if the odometer works then it id definitely the gage. but you are on the right track that is how we test them in the shop if their is a good voltage sweep ( we test them with a lab scope but a good volt meter will work as well ) have fun let me know if their else any thing else i can do for you

for the tire?

try undoing filler cap. vent may be blocked

REMOVE THE PLASTIC COVERING FROM THE STEERING COLUMN UNDER THE STEERING WHEEL. YOU PROBABLY WON'T HAVE TO REMOVE THE WHEEL. THERE SHOULD BE SCREWS ON THE BOTTOM SIDE OF THE PLASTIC PIECES . THE SCREWS THAT HOLD THE IGNITION LOCK CYLINDER IN PLACE MAY HAVE SECURITY HEADS, [ROUND , NO SLOTS OR HEXES] YOU WILL NEED A SMALL CHISEL & A SMALL HAMMER TO START THEM TURNING.

IF YOU ONLY WANT TO REPLACE THE ELECTRICAL PART, " THE BLACK PLASTIC WITH THE WIRES " ALL YOU HAVE TO DO IS REMOVE THE SINGLE SCREW FROM THE OPPOSITE END WHERE THE KEYS GO & PULL OUT THE PLASTIC SWITCH.

14mpg city
17 mpg highway

Remove the air intake and spray starting fluid into the throttle body while someone is attempting to start the truck (use short burst and don't use too much). If the truck starts and runs briefly then you have a fuel delivery problem. I'm assuming that this truck is fuel injected, so turn the key to the on position and listen for the fuel pump humming. Also, have a mechanic check the fuel pressure at the fuel rail. Any auto parts store can tell you what the fuel pressure should be. If it is below the accepted threshold then your fuel pump is bad. Also check for a relay that controls the fuel pump (rather than a fuse)

"whoa big fellar" before you star pointing at big$ probs try fuel filter. Also when was last tune up? Sometimes something simple as carbon build up can cause lack of power. I would start with a "ground zero" tune up and go from there before you start throwing parts at it to only find out it was dirt in an injector

easy they bolt to existing fittings ,but make sure you are not infringing any local vehicle laws by fitting them ,check with your local vehicle testing station as the vehicle will not pass the annual test unless the steps are on the paperwork of the certificae of homoglonation for this vehicle

get vehicle scanned for a problem code if light is on. 02 could be a bad 02 sensor in exhaust. any auto parts store will scan for free. have a good one !

The reason why your OD light is flashing is the speed limiter in the dash will need to be replaced. It could also mean that your over drive switch on the gear lever has gone bad. The best thing to do is plug in a OBD II scan tool (on board diagnostics) and obtain the trouble code stored inside your Isuzu vehicle computer.

Means you computer has detected a problem and it needs scan to get the Code.

ISUZU HAS A RECALL ON LEAKY INJECTORS ON THAT TRUCK GIVE THEM A CALL The injectors use the engine oil at very high pressure to inject the fuel, and semi synth oil just can't withstand these high pressures for very long. It breaks down, loses it's viscosity, and then the injectors won't work properly.
Change the oil to fully synth, and you should see a huge difference. (Do both oil filters while you're at it too). 1. Injectors. Usually the electronics in them fail and cause a miss fire.

2. Injector Sleeves. Causing diesel to leak into the sump and in severe cases the oil/diesel mixture filling up to such an extent that the vehicle actually runs on its own, on the mixture. This can cause the engine to rev to the maximum until all the oil/diesel mixture is burned or the engine basically destroys itself.

3. Rail Pressure Sensor. If the E.C.U cant determine what pressure is at the rail the vehicle may not start or stop running . A fairly simple fix with only the rocker cover needing to come off.

4. Rail Pressure Control Valve. This controls the pressure supplied to the rail. Engine will not start if this control valve is faulty.

5. Turbocharger. A very unreliable unit. Seals usually go after 50000miles.

6. Dual Mass Flywheel. Seldom give trouble but I have seen a few that have. If the new flywheel is taken off and not put back in the same way as the old one (lined up via a half moon shaped mark) the engine will not start as the flywheel sensor will be unable to determine the position of the flywheel.

7. Throttle Position Sensor. Fairly troublesome. Usually no deteriation in driveability but will bring on the engine light.

The engine is a gem when running correctly but unfortunately its a rare occurrence. I think the 02 onwards models had a lot of modifications done to them such as improved injectors etc.

You are actually causing less wear & tear if you put your foot on the brake & shift into neutral then shift into 4 wheel & out of 4 wheel drive.

your check engine lamp is probably on because the vehicles computer is not receiving a vehicle speed signal, because your speedo is not working. You need to check the sensor on the gearbox and the head unit in the dash cluster. The gearbox sensor has three wires, one is power to the sensor and should read 12volts with ignition on (but engine off), a second wire is the earth for the sensor and should read 0volts and the third is the signal wire which can read anything from 5 to 12 volts. This signal should jump between zero volts and the signal voltage (5 to 12 volts) when the gearbox is rotated by turning a rear wheel (with the other wheels chocked to prevent the vehicle moving..and rotate the wheel by hand as some of these vehicles have a limited slip differential which can cause serious accidents if you try this with the engine turning the wheels...so don't). If the sensor is not getting 12 volts, check fuses and harness connections, if the signal voltage is missing check the head unit as this comes from the head unit to the sensor. If the signal voltage does not fluctuate when the wheels are rotated, or stays at zero volts, suspect the sensor.

Most vehicles run the drain hoses down into the wheel wells. This would give you access to the tubes by removing the plastic inner fenders and probing the tubes with a piece of wire . If leaves have plugged the tubes from the top you will have to take off the windshield wipers, open the hood, and remove the panel that runs across the bottom of the windshield. You will locate the tubes on the outer edges of the vent ares at the lowest points. You should have enough access to reach in with your hand or a yard stick and remove the debris build up blocking the tubes. Again using a long piece of wire (in the tube) and a pitcher full of water you should be able to gently wash the rest of the mud out of the wiper/air vent well and out through the tubes.

Engine not at operating temperature--Cold Converter,Thermostat Stuck Open
Malfunctioning Mixture Control--O2 Sensor reading lean all the time.
Coolant Temp Sensor high resistance or open circuit
Bad Converter

EGR Valve--most likely cause

look in the phone book under welding or fabrication. you need to get someone on it who knows what he is doing. and the thing is over 17 years old, there might not be enough metal left there to work with.

There are three components that will enrich the fuel mix: 1)engine coolant temperature sensor. If this is not working or the signal is interrupted by a wire breakage then the engine will run rich. The coolant sensor informs the ECU (high resistance) that the engine is cold at start up and so the ECU responds by increasing the fuel injection cycle to enrich the fuel air mix. Later on as the engine warms the resistance of the coolant sensor drops and the injection cycle is reduced by the ECU. If the sensor is faulty or has become disconnected (wire break or corrosion of the socket pins) the ECU assumes that the engine remains 'cold' and the engine runs permanently rich. 2) O2 sensor, operates completely independently of the EGR, if it is faulty and signals 'too much oxygen' then the ECU will significantly enrich the fuel mix to try and balance what it thinks is an excess of air. 3) Fuel pressure regulator. If the diaphragm has broken or there is a leak in the vacuum line this will result in higher than needed fuel pressure in the fuel rail at idle. The vacuum line acts against the spring pressure holding the valve closed. At idle, the inlet vacuum pulls back on the diaphragm reducing the fuel pressure required to open the valve. Low fuel pressure coupled with short duration injection times will mean a lean mix at idle. If the vacuum is compromised or the diaphragm damaged then the increase in rail pressure will make the fuel mix very rich to point of flooding the engine

When you do the brakes on those, and your light stays on, try bleeding the brake (start with the right rear, left rear, right front, then left front) Be sure to pump the brakes before you bleed them. If that doesn't work, you may have an issue with your ABS unit, and it might need to be replaced.

For 1993 Isuzu Truck Trooper 3.2L MFI SOHC 6cyl the ECM (Engine Control Computer) is located in front seating area, center, under dash, front of console, mounted on firewall.

Fig. : Component locations-1992-95 3.2L engines (click for zoom)

Hope helps.