Water Pump

[Gooman18]

Hey guys. I'm trying to help my friend get her car running again. We replaced the thermostat and it overheats quickly. It's a 98 Altima with a 2.4 L. Approximately 121xxx miles. It died while she was driving. The cooling fans dont turn on at all when its running, but kick right on when the A/C is turned on. Upper radiator hose is hot and lower hose is cool to the touch. Any suggestions?

[ctwright]

You need a coolant temperature sensor more than likely. This is what sends the temperature data to your ecm which then in turn sends power to your radiator fan relay which then the contacts inside the relay close sending power to your radiator fan. Also a fault with this sensor can affect the fuel injection system. Check the radiator fan relay(s) first though.

I'm also thinking though from what you are describing you still need a thermostat. I've heard of new ones being defective. Take it out, put it in a pot of water, let it boil, and see if it opens up. If not the new thermostat is defective and you should get another one.

[Gooman18]

Could that cause the idle RPM to be very high? When idling the RPM is around 1500 RPM when put in drive it drops below 1000. That sensor, is it sold at Autozone?

[ctwright]

Originally Posted by Gooman18

Could that cause the idle RPM to be very high? When idling the RPM is around 1500 RPM when put in drive it drops below 1000. That sensor, is it sold at Autozone?

It is probably around 20 dollars or so for you vehicle, not sure just call them and ask.

The high idle maybe b/c of that not sure, could be the throttle position sensor, is the check engine light on, faults with either of these sensors should through a code?

[Gooman18]

No no lights at all. Like i said i replaced the thermostat and topped off the coolant. I read that it could be air in the system. I poured the coolant in slowly to try and prevent any air bubbles. Do you think i should bleed the system anyway? She doesn't want to drive it if it's going to overheat.

[ctwright]

Originally Posted by Gooman18

No no lights at all. Like i said i replaced the thermostat and topped off the coolant. I read that it could be air in the system. I poured the coolant in slowly to try and prevent any air bubbles. Do you think i should bleed the system anyway? She doesn't want to drive it if it's going to overheat.

To add coolant, you need to do this, you need to fill it up like you said, till it finally stops going down. You need to leave the cap off, start the car and let it run for 5 minutes or a little more. Stand at the radiator with more coolant to add after the thermostat kicks in and the water starts going down again until if finally fills up to the top again and stops. Then put the cap back on.

[Gooman18]

Ok. Will give that a shot. Thanks.

[ctwright]

PS

I over looked something. It's possible you may have a clogged radiator. You can check this by when you fill it up with water, squeeze on the bottom hose and see if it changes the water level any or bubbles come up, if so it's probably good.

[Gooman18]

we checked the radiator and its good but when the car is on with the cap is off it starts to over flow is that normal?? and btw thank you for ur help.

[ctwright]

Originally Posted by Gooman18

we checked the radiator and its good but when the car is on with the cap is off it starts to over flow is that normal?? and btw thank you for ur help.

Yeah that's when it's time to throw the cap back on. It is doing it while you are putting the coolant in right? Did you notice the level go down any first and have to put more in? How did you check the radiator?

[Gooman18]

ok because it would bubble then we turned the car off and then it gurgled.

[Gooman18]

okay so in the morning when they open we should go get a

BWD AUTOMOTIVE - Coolant Temperature Sensor correct???

[Gooman18]

we used the method you mentioned to check it. im really hoping its the sensor.

[ctwright]

Originally Posted by Gooman18

okay so in the morning when they open we should go get a

BWD AUTOMOTIVE - Coolant Temperature Sensor correct???

Well, I'm trying to figure out why it's not setting off the service engine light. It should be if it's bad. Does the light come on when you first turn the key on? If you don't see a check engine or service engine soon light on when you first put the key in the on position the bulb is probably blown. And something could still be setting off a code and you wouldn't know.

[ctwright]

I'm gonna get off here and get some sleep, write back when you get a chance about the check engine light, I'll try to check back in the morning. I'd hate for you to get a part you don't need. The radiator fan relay may be bad which instead might be the reason for the fans not coming on.