I'm thinking my water pump is going out.

Car overheating. Runs hot around 220-230 while cruising. When i stop at a stoplight, then the temp goes up to the red. But i have found that when i rev the engine to around 2000rpm while in neutral, the temp goes back down.

The coolant level is full. Just topped it off this morning.

The fan relays are bad, but i do have a manual fan switch to turn them on and off.

The coolant light comes on periodically for no reason, seeing how my coolant is topped off.

Any thoughts?

 

Is the weep hole on the water pump leaking? Is the water pump original?

The low coolant light is likely the sensor in the radiator. They are very finicky.

 

There are a FEW cases of the mechanical pump having the impeller come off, I would expect that to cause a complete stop of water flow and rpm would hurt not help.

The mechanical usually fails by leaking out the weep hole. What you are reporting just doesn't sound like mechanical waterpump failure to me. I wonder if you hurt a head gasket with the bad relays and mechanical fan switch.

 

I'll have to check the weep hole. and reving the engine helping it cool off just sounds like the pump starting to go. it's like the higher I rev it, the more it cools off.

 

I can't tell you what the problem is. BUT, I can tell you that my car did that for years before I put an EWP on it. I just always put it in neutral and revved it a little if I was a red light or traffic. I have had an EWP for ~5 years and have never had that happen to me since installing it.

 

I really don't see that as a mechanical pump failure but then again I actually understand things.

Far as the electric pump, they move more water at idle but less at mid to high rpms, you know like the engine sees when it is actually making power.

That did make me think of another possibility though. Maybe the cooling system is just full of junk or the radiator needs to be cleaned inside and out. That is the only conditions I can think of where a mechanical pump being sped up would help cooling on a stockish setup.

Again and maybe read this very slowly so it sinks in, the mechanical pump generally fails by weeping when this happens the impeller is still spinning full speed. There is a timing chain and a gear drive, no room for slip it either spins or something in the system fails and it doesn't spin.

I would view it cooling off with increased rpm as more proof it is NOT the pump than proof that it is. If you find it weeping I would continue looking for the cause of the overheating because weeping wont cause overheating till the level gets low or at the very least you get airpockets.

 

so seeing how there is a possibility that its not the water pump, would you suggest doing a coolant flush? would a flush clean out the inside of the radiator? if I do that and replace the fan relays, and the problem is still there, how would I know if my head gasket is shot?

 

also, my heat isn't blowing hot air

 

I would change the water pump just to be safe, its not that expensive, and its well worth it. If your pump goes out and you overheat, you will likely blow a head gasket or even crack your block from heat, (happened to me about a month ago). The repair costs and hours laboring in my friends garage were much more than the price of the water pump I ended up having to replace anyways....

 

Do you have a thermostat. My friends car did that and the cause of it was no thermostat

 

So there are other cooling system issues you are ignoring. I suggest you find a competent mechanic and write the check because you are not skilled or open minded enough to resolve this on your own.

 

theres a reason why people come to this forum: and thats to learn about these cars. people like you who tell them "oh screw it, go have a mechanic do it" aren't why I come to this board. I know i'm not as skilled as some people when it comes to cars, but i know for damn sure that I can fix them once i find out what is wrong with them. I come here to learn and improve my car knowledge so i can fix the problem. I'm just trying to give you every bit of information i have so we can diagnose it, and I've never said you were wrong in any of my posts. i figured whatever is causing the overheating, may be effecting my heat too, as both problems started at the same time. So before you go posting **** like "go have a mechanic do it", go ahead and press the "back" button on the top of the browser screen and scroll to a different topic. Thanks.

 

further evidence: coolant looks like it needs to be changed. but would this cause such bad overheating?


also bled the coolant system.

 

No heat or low heat is usually a heater core that is gunked up in these cars. Usually...not always

How old is the T-stat? It might be smart to spend the 10$ or whatever it is and get another one. I think oreilly has one for 10$, its nothing special but its something cheap to check. Maybe its getting stuck and opening late? who knows, those things can be tricky when they fail.

Since your fans are running and its still getting that hot, then something def isnt right.

Honestly, The condition of the coolant in the system has always baffled me. We were told as a sales pitch that after it is tested, in the winter say "its more likly to freeze" and in the summer say "it doesnt cool as well". after testing it with one of those floaty doo-hickys (yes I said it). But then you look at people who run straight water and have no issues in the south and coolant is mostly water anyways.

I think you should flush it, just to get the **** out of it. they can be BAAADDDD. I wouldnt do the power flush that some places offer. I have seen people do flush kits on youtube and they get WAY dirtier nastier results then a power flush ever does. I say youtube because i havent done one yet, but seeing what they get out of it is amazing. I used to do power flushes when I was 17 at a quick lube, and they didnt look anything like that, green went in, green came out. the flush kits turn out brown first, till the more you do you get back to clear.

Also, if the car is running with the rad cap off, can you see it moving the coolant through? You should see it being cycled through.

If the rad fans are on, the pump is cycling fluid, and your air dam is intact...The next obvious thing would be to flush it and do a t-stat. When that doesnt work, you should look into a water pump.

You could also bypass all that right now, and go get it tested for a head gasket if you think its that. If it passes that test then do the flush and new t-stat.

Im no ASE mechanic, thats just what I would do if I had your car right now, knowing what I know.

You should get new relays for your fans as well. Wireing them up, unless you have a switch that was made for it with good wire, is a bad idea. Some punk used like 18ga wire on mine and the fuse panel melted. Funny thing is that the fans WORKED when I plugged them into the factory harness!!!!

 

I checked out the relays to the fans. ended up swapping the fog light relay for the fan relay and the fog lights still worked. if the fan relays were bad, wouldn't swapping them to the fog lights cause the fog lights to not work? also, how bad does that coolant look in the picture? when I pulled the coolant dipstick, there was alittle bit of dried up crusty looking stuff on the dipstick. after letting the car get hot and checking the dipstick, there was alittle bit of smoke comming out of the coolant dipstick tube.

 

Your last post makes me think you have more than a bad pump and / or coolant issue. First go google "shbox" and heater core flush to see of that will bring back your heat. It did for mine for a day and then I ended up replacing it since it was so far gone. Next there's a really good write up on this site for flushing your own cooling system / block better than any shop will... But I wouldnt waste time on that yet. rent a cooling system pressure tester from autozone or where ever and see if it's holding 15psi. Report that back. Check your oil. What color is it? The car smoke at all? Was your cooling system level on start up? Check it every time before start up from a dead cold. Once any air is gone the coolant level shouldn't fluctuate.

 

A '96 runs orange/Dex Cool. That pic it looks green. What coolant are you using?

 

I'm not really sure what the previous owner had in it. but i topped it off with some prestone 50/50. I thought Dex-Cool was bad?

 

It's bad if you expect it to live for 100K+ miles without changing it. What's supposedly bad is if you mix the two together. It causes a reaction and the end result is the coolant becoming gelled which fubars the entire cooling system. Is the coolant currently in your system green or orange?

 

i believe it had Dex-Cool in it before, because it was a orangeish-redish color. I wasn't aware you couldn't mix them. I only added maybe a quarter of the prestone jug to top it off. Guess I should do a coolant flush, and quickly too. Do you think that would be the cause of the coolant issues?