1995 Brumby Ute. Running rough. Why doesn't it idle?

1. Error Code 24. Intake Air Temperature Sensor.
Solution:
Check the following:
- IAT Connector and wiring.
- Intake Air Temperature Sensor.
- Engine Coolant Temperature Sensor.
- ECM.
2. Rough Idling when the engine is hot.
The following are the reasons due to which the engine can perform bad when it is hot.
- Fuel pump control circuit.
- Fuel pump pressure.
- Fuel injectors.
- Non Return Valve clogged, located on the lower side of car chassis above the fuel tank.
- Engine compression, valve clearance, spark plugs.

expose the carburetor throat and start the engine keeping it running with your hand on the throttle. try and control the idle at its lowest possible rpm and look inside the throat. if it is showing ANY dripping fuel or even wet flaps then it is stalling because of too much fuel and the carb. will have to be cleaned or serviced.

after water pump did you burp air from system? as for the timing chain did you put the old worn out timing chain in the same postion you taken it off? and you sure you didnt knock off a vacuum hose somewhere. to check that while engine running spray choke cleaner along hoses if idle rises you near the leak ,BE CAREFUL CHOKE CLEANER IS FLAMABLE

Hello Friend:

Your Thermastat is located in a Dome Shaped Housing,just take your hand put it on upper radiator hose and follow it to the engine ,you'll run into a hose clamp around the hose thats holding it on the Thermastat Housing.

Make sure your car is cold, then put a pan underneath vehicle below the thermastat housing,You'll loose a Little Coolant ,So this Way you can catch it.

Just Loosen the Rad. Hose Clamp and Pull off the Hose from the Thermastat Housing.Then you'll have a couple bolts holding on the Housing,Remove the Bolts and The Housing should be FREE to come off.If its a Little Stubborn ,Lightly Tap on It with a Plastic or Rubber Hammer a nd it will come off.Your Thermastat is under the Housing.

After off Clean Both Surfaces on the Housing remove All the Old Gasket material and Gasket Sealer .Then just put your new thermastat housing in with the Spring part facing Up.

Put Gasket Sealer on The Thermastat Housing and Put new Gasket on and Line up your Bolts Holes.

And Also piut a Small bead og Gasket Sealer on The Engines Surface. Tighten Down Good and Snug ,But Don't Over Tighten.

Put the Hose back on Tighten Clamp and Fill Radiator Back up to Top.

Please let me Know how my Answer and Solution Helped you By Voting .Thanks From d_hubbs

Check vacuum leaks , by spraying carburator cleaner around intake manifold gasket and vacuum hoses connections . See if engine picks up the idle speed while you doing it , and if it does , locate leak and fix it. Most common , intake manifold gasket brakes.

I had this problem with a Mazda I had and I did everything I could think of.  Check for vac leaks again and then check air cleaner hoses.  I suggest this, because I found mine right smack dab in the crevasse of the air intake for the air cleaner.

1995 Geo Truck Tracker 4WD 1.6L TBI SOHC 4cyl
The PCV Valve is located under hood, center, upper engine area, top of engine, mounted in passenger side of intake manifold.

The low gas mileage and the versatility that your 1995 through 1999 Geo Tracker offers are two benefits of owning it. The maintenance needs to be kept up on your Geo Tracker. One form of this maintenance is to replace the valve cover gasket once you have driven 100,000 miles or more.

1. Allow your engine to cool. Disconnect the negative battery cable. Remove the air inlet hose and air intake case or air cleaner housing. Detach the PCV valve hose from the PCV valve. Separate and remove the spark plug wires and the accelerator cable from their clips.
   
2. Loosen and remove the valve cover bolts. Lift the cover up and off. Using a flathead screwdriver, gently nudge the gasket out of the gasket seating area. Using automotive engine cleaner and a clean cloth rag, clean the gasket seating area.
   
3. Place the new gasket in the gasket seating area. Put the cover back into place. Put the bolts in and then using a torque wrench tighten them. Do not over tighten the bolts or the gasket will not fit correctly. Reconnect the spark plug wires and the accelerator cable in the holding clips.
   
4. Reconnect the rubber hose to the PCV valve. Install the air intake case, or air cleaner housing, and the air inlet hose. Reconnect the negative battery cable. Add oil to the car and start the engine. Allow the car to run 10 to 15 minutes. This will allow the oil to lubricate the engine while it moves to the top.
   

I hope helps with this (remember rated this help) Good luck.

Explorer Thermostat LocationHere is advice for finding the thermostat:

• Follow the upper radiator hose from the radiator to the engine and there is a housing that houses the thermostat. Take it off and when you reinstall the thermostsat, make sure the spring goes toward the engine.

• The thermostat is located on the motor block under the three bolt flang that the top rediator hose connects to. Remove the three 10MM bolts and the thermostat can be removed for replacement.

How to Change an Explorer Thermostat

• 1. Remove the air cleaner air duct from the throttle body and air cleaner.
• 2. Follow the upper radiator hose to the engine to locate the thermostat housing. The housing is located at the front of the intake manifold.
• 3. Loosen the hose clamp, then detach the hose from the fitting. This can be difficult. If it's stuck, grasp with a pair of adjustable pliers and twist to break the seal. Then pull it off.
• 4. Remove the bolts and detach the housing cover. Be prepared some coolant may leak out as the gasket seal is broken. Remove the thermostat.
• 5. Install the new o-ring onto the thermostat (no gasket is needed) and install the thermostat into the intake manifold with the spring side pointing toward the engine.
• 6. Make sure the air release valve is in the up 12 o'clock position. Install housing cover and bolts. Reattach the hose fitting and tighten the hose clamp. Fill the cooling system with a 50/50 mix of coolant and water, and burp the system.

he thermostat housing is located on top of the motor, underneath the air intake assembly. The easiest way to remove it, is just take off the air cleaner assembly. Unscrew the plastic nut on top of the air cleaner (above the throttle body), and then remove the 4 screws that hold the top onto the air filter box. It will start to lift off now, but there's several hoses and vacuum lines attached. The rubber hoses should have plastic clips holding them in place, these can be CAREFULLY separated with a screw driver, and then just pull the hoses off. The vacuum lines are underneath it, CAREFULLY pull these off, or pry them off with a screw driver. Make sure you remember which ones go where! With this off, the housing is easy to see, the upper radiator hose on the driver side of the car goes right into it. Remove this hose, be prepared to spill some coolant. Have towels ready to catch/mop up what you spill, and have some extra coolant handy to replace what is lost when you're done. There should be a couple bolts holding the housing on, remove these. There might be a sensor in this as well, I don't remember, unplug it if it's in the way. Pull the housing cover off, and the thermostat should be right underneath. It just lifts out, make sure you put the new one in the same way the old one came out, in other words, don't put it in upside down, it won't work. Also, make sure you have a new gasket for the housing, you should never reuse the old one. If needed, clean of any old gasket material or sealant, try not to get any into the coolant. It's not required, but it never hurts to use some RTV sealant when you put the housing back on. Reinstall everything, add coolant if needed, and don't forget to recheck the coolant level after the engine heats up, it'll probably drop once the thermostat opens up.

Here is the most common cause of surges and stalls and low idle rough idle, it is the idle speed control air-bypass valve and throttle valve (IAC for short), they get full of gunk over the miles and cause idle issues (stalls, low idle) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.