Over Heating
 

hello everyone i am trying to help out my neighbor she has a 1998 Saturn sl2 1.9 liter 4 door

she has a overheating problem i have read this thread and have done most of the things yous have posted in here

she went to a shop they replaced head gasket, water pump, thermostat, flushed out radiator and still had overheating problem the shop told her she cant have a thermostat in her car??? she made them put it back in

she came to me for help i found this thread thank yous
i have changed the temp sensor, this fixed the gauge from jumping up an down
i noticed the reservoir tank leaking on bottom she is out now getting a new one also the fan does not turn on i did do the test of turning on the ac full blast fan still did not work i did the jumper test and the fan turned on she is getting new relays for ac and the cooling fan
also the is a new reservoir tank cap

if this does not work what else could it be? thank you

On a car that age, I would replace all the hoses if they have not been changed before. Hoses have a couple layers to them and sometimes the inner layer can collapse and block coolant flow, but the outside looks good.

One hose I would pay particular attention to is the bleed hose. It is a very small hose (diameter) that goes from water outlet on the drivers side of the engine to the bottom of the reservoir. Part of the line is a hard line (steel) and part rubber. I would replace the rubber, but check that the steel part is clear. If this hose is blocked in any way, air will get trapped in the engine and it will overheat, no matter how much you do to the rest of the cooling system.

Let me add something here, when the engine starts to overheat, she should turn the heater all the way to the hot position and the cabin fan to 3 (next to the highest speed). If she does not feel hot air coming out the vents and the coolant temp doesn't start to drop, that is a strong indication that the bleed hose is blocked.

well i just let the run and the new cap started to leak the car the got to almost red zone on gauge an fan still didnt turn on the antifreeze started to shot out of car

Go get a pressure tester at your local Autozone or Advance on the loan a tool program and run a pressure test on the system. Any leaks should show up. You put a deposit on the tool and when you return it, you get your money back.

okay we are going to take all coolant lines off and see if there is anything blocking the replacing bad ons then will do a pressure test..

what about this fan not turning on at temp or with ac on?:confused: remember already changed temp sensor fan relay and did the jumper test ( ran a wire to lower left to upper right prong hole) and the fan works

About all I can suggest is to start tracing some wires and see if you can find either a broken or frayed wire or maybe a corroded connection. Wish I could be of more help, but I'm more of a "hands on" type of mechanic.

On these cars the fan is controlled by either the engine computer or body computer

RjS take a minute and go to the new member area and give yourself introdution. When done open the USER CP and add your first name, location, and car info to your "signature".

When you jumpered the relay, you just proved that the fan is working and that power is getting to the relay. The relay needs to be replaced.

Not clear, has the relay already been replaced? If so, pull the relay and jumper the two rear (in relation to the front of the car) and see if the fan comes on. If not, the jumper wire underneath the underhood fuse block is open. If it does come on when jumpered but not when the AC is on, then pull the relay and check the front/passenger side pin for continuity to ground with AC on. That is the wire that goes to the PCM to find ground to turn on the relay. I would suspect a bad wire before a bad PCM unless the PCM has a bad ground, but I think that would cause a lot of other issues.

But I'm not sure that is your whole problem. It would be if the car only overheated with the AC on, but with this cold weather, the fan should not have to come on to keep the engine cool. I'd be looking for a blocked hose. Then I'd check for exhaust gasses in the coolant, possibly the head gasket job wasn't done right or the head or block is cracked.