andresr23

A/C: THE A/C IS ONLY WORKS AT THE VELOCITY OF 4 AND AT TIMES IT DOESNT BLOW AIR THROUGH THE FRONT VENTS, ONLY THROUGH THE TOP ONES ON THE DASHBOARD. SOMETIMES I LEAVE THE VELOCITY AT EITHER OF 1,2, OR 3 AND IT WORKS FOR A WHILE AND THEN IT STOPS WORKING. I ALREADY REPLACED THE RESISTOR. DONT KNOW WHERE TO CHECK NEXT.

ENGINE HEATING UP: IVE NOTICED THAT WHEN DRIVING IN THE CITY AND THERE IS USUALLY ALOT OF TRAFFIC, THE TEMPERATURE TENDS TO GO UP. I TURN ON THE A/C AND THE TEMP GOES BACK TO NORMAL, BUT IF I HAVE THE A/CC OFF, IT HEATS UP UNLESS IM DRIVING HIGHWAY SPEEDS. THE TEMP ALSO RISES WHEN I USE THE 4X4.I HAVE A NEW RADIATOR AND A NEW WATER PUMP INSTALLED ABOUT 2 WEEKS AGO.

IVE ALSO NOTICE AN ISSUE WHEN I PRESS THE GAS, IT DOESNT WANT TO ADVANCE, LIKE IF IT CHOKES UP, AND IF I FLOOR IT I HEAR A SLIGHT POPPING NOISE AND IT TAKES OFF LIKE NORMAL, LIKE IF SOMETHING IS CLOGGED UP OR LIKE A MINOR VACCUM LEAK. I REPLACED THE TPS SENSOR AND THE IAC VALVE ALSO.

ANY SUGGESTIONS?


99 XJ
4.0 INLINE
4.5 RC SUSPENSION LIFT
31s GOOD YEAR DURATRACS

davejelly

Alright lets tackle this one at a time.

1. Get an OEM quality blower motor resister. Look into the quality of your climate controls?

2. Does your electric cooling fan kick on when you turn the AC on? (Its driver side behind the radiator) The fan should kick on immediately if the AC is turned on. It should also kick on when the engine hits a certain temperature (Can't remember the temperature exactly). Its possible the fan is running when the AC is on because its the first part of the circuit... If the fan is waiting on a faulty temperature sensor it might never kick on if the AC is off. Make sense? Im leaning towards a faulty fan or sensor or both.

3. Lets fix 1 and 2 first.

Tex-J

[QUOTE=andresr23;3086363]A/C: THE A/C IS ONLY WORKS AT THE VELOCITY OF 4 AND AT TIMES IT DOESNT BLOW AIR THROUGH THE FRONT VENTS, ONLY THROUGH THE TOP ONES ON THE DASHBOARD. SOMETIMES I LEAVE THE VELOCITY AT EITHER OF 1,2, OR 3 AND IT WORKS FOR A WHILE AND THEN IT STOPS WORKING.

Stops working entirely or stops blowing through the main vents and just blows through the defrost vents? If it stops working entirely, then it's likely a bad resistor and/or install. If it continues to blow, but only through the defrost vents, then it's likely a bad blend door.

I ALREADY REPLACED THE RESISTOR. DON'T KNOW WHERE TO CHECK NEXT.

See above.

ENGINE HEATING UP: IVE NOTICED THAT WHEN DRIVING IN THE CITY AND THERE IS USUALLY ALOT OF TRAFFIC, THE TEMPERATURE TENDS TO GO UP.

Goes "up" to what? Just a little over 210? To 220? 240?

I TURN ON THE A/C AND THE TEMP GOES BACK TO NORMAL, BUT IF I HAVE THE A/CC OFF, IT HEATS UP UNLESS IM DRIVING HIGHWAY SPEEDS.

Sounds like your mechanical fan clutch is going out. In your '99,turning on your AC kicks on your AUX cooling fan, which is why the engine temp drops when you turn on the AC. Otherwise, the coolant temp sensor on your thermostat housing should be turning on the AUX cooling fan on at 220f, even with the AC off.

THE TEMP ALSO RISES WHEN I USE THE 4X4.I HAVE A NEW RADIATOR AND A NEW WATER PUMP INSTALLED ABOUT 2 WEEKS AGO.

Check your mechanical fan clutch.

IVE ALSO NOTICE AN ISSUE WHEN I PRESS THE GAS, IT DOESNT WANT TO ADVANCE, LIKE IF IT CHOKES UP, AND IF I FLOOR IT I HEAR A SLIGHT POPPING NOISE AND IT TAKES OFF LIKE NORMAL, LIKE IF SOMETHING IS CLOGGED UP OR LIKE A MINOR VACCUM LEAK. I REPLACED THE TPS SENSOR AND THE IAC VALVE ALSO.

That problem could be a multitude of things. As the other poster said, get your overheating issue figured out first, then go from there.

extrashaky

If I'm reading your description correctly, it sounds like a vacuum leak. The vents are operated from vacuum. If there's a vacuum leak, it can make the air come through the defrost vents only and not through the dash vents.

Sounds like a bad fan clutch. The temp is normal at highway speed because air is moving through the radiator. When you stop, the viscous fan clutch is supposed to start turning the fan as the temperature rises to pull air through the radiator. Yours has failed, so it's not turning the fan when it's supposed to.

The fan clutch is around $40 and not a difficult fix. I find it's easier to do if I remove the upper radiator bracket so that I can tilt the radiator to give me a little more room to work.

Sounds like your electric fan is working correctly. When you turn the AC on, it kicks the electric fan on, which brings your temp back down. The electric fan is also supposed to kick on at a set temperature, but only as a backup to the mechanical engine fan.