Engine Overheating? cooling fan starts working too late?

Any signs of overheating besides the temp gage? Is the coolant level OK? Does the coolant in the recovery reservoir boil or boil over? How long since you changed the thermostat?

Some fans won't kick on till about 220 degrees. You may need to use an infra-red temp detector to double check your gage. You just point it at your engine and pull the trigger, it gives you a temp read-out in degrees F.

Any applicable trouble codes? Some of the national brand autostores will check codes for free.

Any signs of overheating besides the temp gauge?
- Yes

Is the coolant level OK?

-OK

Does the coolant in the recovery reservoir boil or boil over?
- No

How long since you changed the thermostat?

-In a week


Some fans won't kick on till about 220 degrees. You may need to use an infra-red temp detector to double check your gauge. You just point it at your engine and pull the trigger, it gives you a temp read-out in degrees F. Any applicable trouble codes? Some of the national brand auto-stores will check codes for free.

- Above your comment, I understand it!

Excuse me, please see my add image. I think when engine temp goes over point number One, fan kicks on. but engine temp is over point number Two, Fan works, and temp needle is on center, fan stops!
What happen?

Another thought, maybe something wrong with fan motor. I've seen faulty fan motors, run intermittently. Took fan motor apart and those little brushes were wore down to the nub.

Maybe Fan control has problem?

You could check voltage and ground at the fan connector when problem is ongoing. I can't think of anything else.

The fan does not run intermittently. As you can see, Fan kicks on too late, it stops so early.

Good morning!

Is it Ok that I add to engine the fan control, "Hayden Automotive 3651 Adjustable Thermostatic Fan Control " that it is found on www.amazon.com for Chevy venture 1999?
I guess that it is not bad thinking.
How do you think of it?

Your low speed fan relay energizes at 221 degrees f. It should energize if the ac is on.

All three fan relays should energize if the temp exceeds 235 degrees F or the ac pressure is greater than 275 psi.

I'd have to verify the temp in degrees F. If the fan/s are cutting on and off, that is intermittent.

Check for trouble codes. If there is a problem with the pcm--cooling fan relays-- or coolant temp sensor wiring circuit, there should be trouble code.

I can't comment on that aftermarket part you are thinking about using, I've never used it. You will have to do what you think is best. It's your decision.

I have a 2000 Chevy Venture and have the same problem, but I wouldn't say the fans turn on close to the red. The fans turn on when the temperature gauge points to about the 2nd mark past the top. Chevy venture fans turn on at about 220F, which in my opinion is way too hot. I suspect GM designed it that way so the engine and transmission will fail sooner. Heat is like the main cause for engine and transmission failure. Chevy ventures have alot of transmission failures and I wouldn't be surprised if it has something to do with this 220 degree fan turn on design. I don't know this for fact, but it's what I'm suspecting. I'm going to purchase an aftermarket fan controller for my venture and set it so that the fans turn on at about 180 to 195 degrees F. In the old cars, with fans driven directly by the engine drive shaft, the fans turned on as soon as the engine was turned on. The speed of fan varied with the speed of the engine. With my Venture, the fans hardly ever turn on even though it runs quite hot. This in my opinion is just wrong.

Hey,

Great addition to this thread! Please feel free to help out on the site whenever it can add information that will help.

Best, Ken

1999 Chevy Venture 6 cyl Front Wheel Drive
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The car is overheating and backing coolant out the overflow bottle. After about 10 minutes the cooling system will go to about 20 psi. The engine starts right up and runs smooth. Is this a cause of lower engine damage or is it just a bad head gasket, and why.

did you have a leak or work done to it recently. you may have a air pocket causing the coolant to overflow. check and see if there is a leak.

I have the same problem and it was the result of a leak. The problem i am having is getting the air out,i would appreciate any ideas to help with this.

open both bleeder screws once in a while when the van is running, this will help remove any air in the system

Engine Cooling problem
1999 Chevy Venture 6 cyl Two Wheel Drive Automatic 93000 miles

Van lost heating, my husband replaced thermostat, it acted up again, so he replaced another element (cannot recall name). A few weeks later, van lost heat & i noticed it was overheating. I tried to drive home, the van powered down 1 block from home - waited a few mins & continue to drive home.

Husband was done fooling with this, and I took van to family mechanic to have another thermostat put in. Mechanic says it has a blown head gasket & wants $1500.

We do not concur with his diagnosis because all fluids are where they should be. There is no evidnce of any loss in oil, trans fluid, or coolant.

Currently looking for another mech that's quick (other mech we know has a back-up of at least 1 week all the time).

Any suggestions? Would you agree with a head gasket? Is there something else we should be looking for?

[quote:610e1fbe5b="marthfamily"]Engine Cooling problem
1999 Chevy Venture 6 cyl Two Wheel Drive Automatic 93000 miles

Van lost heating, my husband replaced thermostat, it acted up again, so he replaced another element (cannot recall name). A few weeks later, van lost heat & i noticed it was overheating. I tried to drive home, the van powered down 1 block from home - waited a few mins & continue to drive home.

Husband was done fooling with this, and I took van to family mechanic to have another thermostat put in. Mechanic says it has a blown head gasket & wants $1500.

We do not concur with his diagnosis because all fluids are where they should be. There is no evidnce of any loss in oil, trans fluid, or coolant.

Currently looking for another mech that's quick (other mech we know has a back-up of at least 1 week all the time).

Any suggestions? Would you agree with a head gasket? Is there something else we should be looking for?[/quote:610e1fbe5b]

Check coolant again with vehicle running is it bubbling if it is does it smell like exhaust fumes? if it does then yes you most likely have a blown head gasket. And that is also causing the over heating.

Another thing to check is your radiator, with engine cold run your finger up or down the fins if the turn to dust then most likely you need a radiator. Also check radiator cap.


.

Engine Cooling problem
1999 Chevy Venture 6 cyl Front Wheel Drive Automatic
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Could you please tell me where the thermostat is located on the engine? Thanks

it is located on the back side of the engine below the throttle body

Engine Cooling problem
1999 Chevy Venture 6 cyl Front Wheel Drive Automatic 89500 miles

When ever I turn on the air on the car, there is a very loud noise coming from the engine, like if there was something hitting every time it turns. As soonest I turn off the air, the noise goes away. What do you think would be the issue?

Check and suspect AC compressor clutch

Engine Cooling problem
1999 Chevy Venture 6 cyl Four Wheel Drive Automatic 138000 miles

THE LOW COOLANT LIGHT HAS COME ON AND IS NOW BLINKING CHEACKED FULID AND IT IS FULL WAY IS THE LIGHT ON

If coolant level is full but low coolant light remains on , suspect faulty coolant level sensor

Engine Cooling problem
1999 Chevy Venture 6 cyl Front Wheel Drive Automatic

I bought this 1999 Chevy Venture when I was driving it would stay cold for a long time then heat up then drop down cold again and keep doing that I changed the thermostat and the waterpump is good
there is no head gasket problem and the fan seems to be working.What is my next step?Flushing my system?or could it be a sensor?

Hi:
When you say it heats up then cools down fast, are you refering to the engine temp or the heater in the car? Also, if you replaced the t-stat, did you bleed the system? You may have an air pocket causing this to happen.

Let me know.

Joe

Engine problem
1999 Chevy Venture 6 cyl Automatic 100509 miles
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my engine is over heating in I have exhaust coming in from the vent if i turn on the heater or air. I do not have water in oil. I check to see if I crack head .Do you think my fan has gone out

[quote:6a00f8c677="linda powell"]Engine problem
1999 Chevy Venture 6 cyl Automatic 100509 miles
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my engine is over heating in I have exhaust coming in from the vent if i turn on the heater or air. I do not have water in oil. I check to see if I crack head .Do you think my fan has gone out[/quote:6a00f8c677]

Ok first I have a overheating problem well I did a couple things ive put it back together and now I believe I did not connect the vacuum lines correctly it shuts off right away

It sounds like you have a vacuum leak. here is a guide to help you find it with the vacuum hose routing diagrams:

https://www.2carpros.com/articles/stall-at-idle

Check out the diagrams (below). Please let us know what you find.

my 1998 chevy venture is overheating but not loosing coolant from radiator but u smell anti freeze resovoir fluid is orange

Then you have a leak....either a hose or intake manifold gasket...pay the 97 bucks to have Chevy diagnose it...it is WELL WORTH IT!

if you smell it inside the vehicle your heater core most likely has a leak, before taking it in another thing to check is the coolant level in the radiator, sometimes it the cap is bad, or the resevore tube isnt down far enough it won't drain into the radiator. this happened to my inlaws 98, they had no heat and just looked under the hood at the tank when we went to change the thermostat we discovered the radiator was half empty

Engine overheated. Had already replaced the radiator because of a leak. So next was the water pump and thermostat. That didn't fix the problem, so the manifold intake gaskets were replaced. It was OK for awhile, about 50 miles. The needle will flucuate rather wildly, going up when idling at a light, then back down while moving. The radiator overflow tank will be totally full. When the bleeder valve is opened a lot of air will escape. No coolant in the oil. Mechanic says it could be head gaslet, but could also be cracked block or head. He recommends putting in a different engine. Last time I drove it any distance, I stopped at about 80 miles because it was staying very hot, opened the bleeder valve, bleed out a lot of air. What can or should I do?

Hello
Thanks for the donation.

You need to have a dye test performed on the engine that will reveal any cracks in the head gasket and the heads. I would not go buying a new engine just because of this issue. I am not sure why the mechanic would have told you to do this without first performing the tests to ensure that the heads are indeed damaged and needing replaced. If it is only a head gasket then it would be better and cheaper just to replace the gasket, not the whole engine..



Thanks for using 2CarPros.com!

My mechanic said he hadn't done the dye check, but had checked carefully and couldn't find any evidence of any leeks. I have been driving it for a couple of weeks, I open the bleeder valve when I park(usually a lot of air). Before I head out I close the bleeder valve, and often add to the radiator. The overflow tank is totally full, but the radiator will accept a couple of quarts, added slowly so air can escape. No sign of antifreeze leeks, or white vapor at the tailpipe. Where is it going? It hasn't overheated, but the needle flucuates, from cold while moving, up to hot while idling and back down again when moving.


[quote:9253e98659="bluelightnin6"]Hello
Thanks for the donation.

You need to have a dye test performed on the engine that will reveal any cracks in the head gasket and the heads. I would not go buying a new engine just because of this issue. I am not sure why the mechanic would have told you to do this without first performing the tests to ensure that the heads are indeed damaged and needing replaced. If it is only a head gasket then it would be better and cheaper just to replace the gasket, not the whole engine..



Thanks for using 2CarPros.com![/quote:9253e98659]

Still showing symptoms of a blown head gasket or cracked head to me.. Without performing the dye test there is really no way to tell for sure if the head is cracked but if your mechanic saw no signs of the gasket being cracked than it is likely that the head itself is damaged.

Had thermostat replaced two weeks ago. Have less than 300 miles since. Also the fluids were changed. My low on coolant light has been coming on every two weeks ,since about 100,000 mi.so I add coolant mixture to overflow frequently. Have had overflow tank changed and waterpump and hoses. I live on ss so don't have maintenance money. Friends have been working on it.

Had thermostat replaced two weeks ago. Is it still overheating after the replacement?

Have it block and pressure tested-do the block first to pinpoint a combustion leaking into the cooling system or a gas analyzer to sniff for hydrocarbons at the radiator fill neck.

Pressure test: do not do a pressure test if there's leakage at the headgasket this might cause coolant into the cylinders and lock it up or bend a connecting rod if cranked thereafter. The headgasket should be repaired before doing the pressure test.

If the block and pressure test passes check the following: Thermostat,Pressure test the Rad. cap,Clogged radiator,Fan clutch,Radiator electrical fan,collaspe hoses,water pump.

Thank you for your quick reply. I'll talk to my mechanic, I guess that's why he looked for engine. He mentioned something called Blue(something)that is supposed to fill cracks, etc. Said he still had half a can(enough to do the job). He didn't like it and didn't want to use it. But my question; if the engine needs to be replaced anyway, what would it hurt to try. Do you know the stuff and what other problems it may cause?
The van looks good and runs good, otherwise.
Thanks, Alice

Thanks for the info. Doesn't sound good.

The pressure in the cylinders during compression will usually blow away any gasket sealant that you use so I don't recommend it. Since you are probably going to be getting a new engine however, it really isn't going to hurt anything to use it as a temporary fix.