overheating help please!!

[gophrsplatter]

can anyone suggest what i should do with my car. after 4-5 miles it overheats and i have to park it and wait till it cools, i've heard it might be the termostat going out or the water pump or there is air in the lines and the radiator needs to be bled. last night in the cold night air i drove fine slight noise when gas is pressed down like a click click click noise, very slight though only when gas is added stops when i take foot of gas pedal, then the resovoir will be bone dry the next morning i thought it sounded like the thermostat is stuck b/c last night it took a while driving around at 25 mph speeds to test it riding slow with 1000-2000rpm and the temp said the engine is still cold but when i gave it more gas to test acceleration the temp sensor jumped up and would remain up like there was no cooling. just changed oil and filter and replaced all fluids which helped a little but when driving down the street it overheats and takes 15-30 min to cool down. couple weeks ago had it overheat when i was pulling into my neighborhood and on the turn the whole thing shut down. there is no noticeable leak on any hoses, the heater worked fine before but not very well when i tried it last time. any help will be appreciated i just need to figure out if i should just take it to a shop or if i can do this so i can get back out on the road again. also it idles a little higher by a couple hundred rpms at tops 1000rpms. ususally at 6rpms. no major leaks very minor but can see older fluid leakage and a couple drops of green fluid from radiator no puddles on ground.
Modified by gophrsplatter at 1:45 PM 3/13/2006

[ItzGenX]

When it comes to the cooling system, you do not want to leak or lose ANY coolant. When you come up with missing coolant, usually there's a problem. Now you need to find out where this fluid is going. Depending on what car you have will also help figure out the common problem for the scenario. I personally think you should stop driving it. Overheating causes further damage to the engine itself due to the heat stress and warpage possibility. Are you burning coolant? (sweet exhaust smell) Pull the thermostat housing and pop the thermostat out (not usually hard on most cars, especially nissans). Then reinstall the housing without the thermostat, so that you can rule out one problem. Correctly fill the cooling system with the engine running and heater on full blast. To help evacuate some of the air in the system, you could either open the bleeder screw or lift the front of the car off the ground about 2 1/2-3 feet. As the system warms up, continue topping the coolant off as needed until the temp gauge is normal and radiator is fairly warm (almost hot) to the touch. Do a final top off, put the cap on (make sure the black rubber at the bottom of the cap is not chipped or cracked, if so get a new one). Now fill the reservoir to the 'min' line and let it idle while you watch the temp gauge for overheating (do not let it overheat). If it does want to overheat, then you have other problems. Also, make sure there is no compression bleeding into your coolant. To test this, open the radiator cap and top it off (when cold). Start the engine and get a little warm (doesnt have to be operating temp). Now rev the engine to about 4k. Have someone watch the coolant as this is being done (remember the cap is off). It should SLOWLY run over the sides and then go back DOWN. If it SHOOTS out, you have a blown head gasket for sure. If that test goes fine, there is still the possibility with the head gasket being blown and coolant burning into the exhaust (white smoke/steamy--neutral/sweet smell). It is best before you do any of these tests, buy a bottle of cooling system flush for $5 at an auto parts store and flush ur coolant system as it tells you on the bottle. It also wouldn't hurt if you take a look at your water pump. You can warm up the car and look at ur water pump as the engine is running. On the water pump, there is a hole somewhere on it behind the pulley that will leak if the water pump seal or bearing has gone out in it. Also, if you are feeling adventurous, pull the pump and inspect how the impeller looks (could be rusted and missing a fin or two). As it has been stated, it is tough knowing exactly which route I gave you since we do not know what car you have, so I gave you a little of everything.

[gophrsplatter]

my exhaust is burning normal same smell and no white smoke, last night i tried to drive it to get the temperature up there was no reading at first but 1.5-2miles into the light drive the temp gauge goes up to the middle and stays i pulled into a 7eleven to let it cool down but i didn't let it get close to overheat i think it is a temp sensor but i don't know how to take off the housing i know where it is but need help.

[gophrsplatter]

the temp gauge won't read at all but will suddenly jump up to mid range and will go higher if i go over 1krpm or cruising ....didn't sound like water pump wouldn't there be a loud pinging noise from the bearings??i'll bled and flush the system tommorow but i think it might be the temp sensor especially since it is probably stock and there's 144k on it...someone let me know how to go about changing temp sensors on a 96 240sx se. ican find the radiator hose fitting but how to get in..

[s13_drftone]

check termostat, and water pump

[180fan]

There is probably air behind the thermo. Behind that same thermo housing, you'll see nearby a sensor with a yellow or red plug. That's the CTS for your ECU. The one next to it with a single spade is the one for your instrument cluster.

What could be going on is an air bubble right at this housing and when the hot water behind the sensors gets up to the sensors it causes the temp gauge to jump and the ECU to say "oh snap, things aren't quite as they seem!"

If you're changing coolant, it'd be a good idea to change the sensors as well.

[gophrsplatter]

now i have a problem i went to pull the car in today to change the thermostat and there is a leak on the frontside of my engine block...looks like the underside of the water pump possibly.. could the coolant be backed up enough to cause this it is about a drop every 30 seconds small right now but i'm sure will get bigger within the day...should i just take it to a shop..it sounds like a water pump gasket has started to go..i just got the thermo though should i still try the thermo and system flush?? if there is a leak like that the resovoir tank was 2inches lower today than a couple days ago...i don't think it's a head gasket..no oil leak, no white exhaust smoke or sweet smell...just sounds like a leak on a gasket maybe...how long should stock gasket last on that water pump about 20k miles ago?? if there is a leak then the new fluid or flush or changing the thermo won't matter right?? also if it has a leak like that could that be the cause of the overheating or a side effect of the heat? i don't think it's a bearing b/c the noise but with a leak or the compression lost be enough to make thos readings come up like they have been...someone please post a reply asap any help is appreciated thx.

[180fan]

The water pump gasket is just some RTV. Yeah if the leak is coming from the weeper hole at the bottom of the water pump you're in for a new water pump. Those should last quite a while though. Check to see if the leak is coming from the water pump meeting the block or the actual water pump.

I suspect you just need to pull the water pump and redo the sealant on it. No biggie. Just be sure to get enough rtv there but not so much you clog up the works.

[gophrsplatter]

there is no more overheating i drove around and kept it idling to check ,i replaced the thermo and seal and added more coolant...when engine is running more drips from the fluid hit ground..i can kind of hear a bearing when i drive ..looks from underneath the leak can't see from top but it is directly below the water pump... when i stoped i can hear air bubbles bubbling in the resovoir but the temp gauge never went above normal...car had surges when i first started it...revs at 1000rpm once warmed up it droped down to 6-800rpms...doesn't leak bad when off..once every 30 seconds when car was warming up1 every 3 seconds. can i get some kind of stuff from autozone to stop the leak or will i have to pull the whole water pump off...if that's the case i'll take it to my buddies at the shop let the m have some fun...

[180fan]

Not much of a fan of stop leak. It's a bandaid for a bigger problem. I say pull the pump regardless and finish off the problem before it gets worse.

[gophrsplatter]

i can smell the sweet smell in the exhaust when the engine is warming up but no white smoke, will the car be alright for a couple days or how important is it to change out the gasket.. can i get to work w/out blowing up?

[rogoman]

i can smell the sweet smell in the exhaust when the engine is warming up but no white smoke, will the car be alright for a couple days or how important is it to change out the gasket.. can i get to work w/out blowing up?

If you smell the 'sweet smell' in the exhaust and you're losing coolant at an appreciable rate; also observe if there is a lot of moisture at the tip of the tail pipe after the engine is fully warmed up, then there may be a blown head gasket.

If there's a small leak at the water pump, don't be too concerned, but if the water pump is making noise, replace it ASAP or else when the pump shaft breaks, you'll have major problems.

[gophrsplatter]

there isn't any fluid on the exhaust but the exhaust smelled differently than normal.i guess when the car overheated it also warped my wire tops b/c now they don't touch the block when all the way down, there is definently a leak at the water pump gasket but i'm not 100 percent about the head, will the water pump gasket be enough to cause another overheating? just on the bottom right half of the gasket. how much are water pumps going for at a good price.

[S13Coupe]

I think waterpumps are about $30-$40, but I'm not sure exactly what it was last time I got one.

[gophrsplatter]

someone tell me if this sounds like a head gasket...my car surges when accelerating like a jump in the transmission but the transmission is fine, also does my resovoir tank sound like the coolant is gasping for air when i park it .

[180fan]

Headgasket, pop the oil filler. if it looks like coffee, headgasket.

[gophrsplatter]

when i stop the car and turn it off i can hear the radiator fluid bubbling like it's gasping for air in my resovoir tank...why is it doing this?

[rogoman]

when i stop the car and turn it off i can hear the radiator fluid bubbling like it's gasping for air in my resovoir tank...why is it doing this?

What could be happening is that there may be a blown head gasket which is causing some cylinder air to be pushed into the coolant system; some of this air may be finding it's way to the reservoir.

You need to do a compression test on all the cylinders.

[IvoryJ30t]

you should be able to find a head gasket test kit.

it detects the presence of combustion byproducts in the coolant.

the bubbling is either a bad head gasket, or a faulty radiator cap.