cooling problems
Thread Starter
Newbie
Joined: Apr 2005
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cooling problems
The electric fans are not clicking on. I set them direct temporarily to avoid over heating. at low rpm the keep the temp normal. at high rpm the temp is above 100.
I have a mechanic replacing different parts, the problem still there.
I need your help
I have a mechanic replacing different parts, the problem still there.
I need your help
MBWorld Fanatic!
Joined: Nov 2001
Posts: 4,260
Likes: 6
From: Philadelphia area
2010 ML550, 2010 E350 4M, 1966 Corvette Convt C2
Well its not a bad fan motor as they come on when wired direct. Then its either a bad fan relay, bad temp switch or possibly a problem with the circut. Should not be difficult to trouble shoot if your shop is decent. But since they wired them direct which is a poor excuse for a repair I think you should find another shop.
Senior Member
Joined: Mar 2005
Posts: 462
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From: By the City by the Bay, CA
2001 E320 (210.065), Brilliant Silver; 2002 Ducati ST-2, Arrest-me Red
Potentially different problem
The fans do two things, keep air moving through the radiator at low vehicle speeds and cooling the A/C condenser when you have the A/C on.
However, if you are seeing overheat when driving at speed, then you have a different problem because the car's own movement through the airstream is what cools the radiator, not the fans. On different vehicles I've seen loose (or corroded-through) impellers do this, as well as blocked cooling systems, debris between the radiator and condenser (you'd be surprised what can get in there), missing air deflectors, bent cooling fins, bad thermostats, worn out hoses (that were so soft they sucked themselves partially closed, thus limiting coolant flow), etc. Add in an ECU that might be over-leaning the mixture causing the engine to run extra hot, or a clogged catalytic converter (same result) and there are myriad potential culprits.
All of that aside, I agree with the other post: get the car to a different shop. Anyone can change spark plugs and rotate tires, but chasing issues like this is what separates the men from the boys.
Good luck and post a follow-up with the final fix,
Greg
However, if you are seeing overheat when driving at speed, then you have a different problem because the car's own movement through the airstream is what cools the radiator, not the fans. On different vehicles I've seen loose (or corroded-through) impellers do this, as well as blocked cooling systems, debris between the radiator and condenser (you'd be surprised what can get in there), missing air deflectors, bent cooling fins, bad thermostats, worn out hoses (that were so soft they sucked themselves partially closed, thus limiting coolant flow), etc. Add in an ECU that might be over-leaning the mixture causing the engine to run extra hot, or a clogged catalytic converter (same result) and there are myriad potential culprits.
All of that aside, I agree with the other post: get the car to a different shop. Anyone can change spark plugs and rotate tires, but chasing issues like this is what separates the men from the boys.
Good luck and post a follow-up with the final fix,
Greg
Thread Starter
Newbie
Joined: Apr 2005
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Thanks for the response, there are two issues here.
1) The electric fans are not click on. With or with out a/c.
2)With outside temp. below 75 degrees F. The engine temp. at high or low rpm for 2 or 3 hours of use is below 100C. Highway or city use.
With outside temp above 80 degrees F. The engine temp. goes to 110 C at high rpm after a couple of hours of use and with the a/c on at high or low rpm.
What has been done:
remove electric fans and clean the condenser unit.
replace cooling fan blade.
replace temp. sensor on top of engine, two pin sensor.
replace sensor by water pump.
replace coolant and flush it twice
What I am about to do:
Later this week I am bringing the car to another repair shop.
What I am trying to avoid is replace a lot of part and not resolving the problem.
Again, thank you guys for your suggestions.
1) The electric fans are not click on. With or with out a/c.
2)With outside temp. below 75 degrees F. The engine temp. at high or low rpm for 2 or 3 hours of use is below 100C. Highway or city use.
With outside temp above 80 degrees F. The engine temp. goes to 110 C at high rpm after a couple of hours of use and with the a/c on at high or low rpm.
What has been done:
remove electric fans and clean the condenser unit.
replace cooling fan blade.
replace temp. sensor on top of engine, two pin sensor.
replace sensor by water pump.
replace coolant and flush it twice
What I am about to do:
Later this week I am bringing the car to another repair shop.
What I am trying to avoid is replace a lot of part and not resolving the problem.
Again, thank you guys for your suggestions.
Newbie
Joined: May 2005
Posts: 1
Likes: 0
cooling problems
Try checking the flow out of the water pump. Ity is a common problem with aluminum impeller blades to corrode off. Usually this is more apparent at low speeds where there is less air cooling on the rad fins, but it's still worth a look
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From: Hollywood North
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Hopefully this may help someone who has this problem today:
TO CHECK TO SEE IF BOTH AUXILIARY FANS ARE WORKING DO THIS TEST:
Step 1 - With the car off, insert key and turn ignition to the second position where the lights are lit up on the dash.
Step 2 - Press and hold both "Auto" buttons on the Climate Control unit for approx. 10 seconds and then let go (Try it again at 15 seconds if this test does not work the first time with 10 seconds).
- Both Black Auxiliary Fans should turn on and spin.
If only one fan spins, you may have a problem with the fan itself, the fan relay or a circuit to the fan. The chances that both fans do not spin during this test is very slim as both fans should not break around the same time.
The issue that I had was that the Driver's side Auxiliary Fan was shot and did not spin during the test. The Passenger side auxiliary fan was spinning. So, I swaped out the driver's side fan and viola. Fixed - spins. Comes on at approx. 103 cel and shuts off at 98 cel.
Another tip if your car starts to overheat while driving is to manually turn on the fans by doing Step 2 above while driving - this can save your engine/head gasket. My stealership thought that it was the viscous fan clutch and recommended that I change that, the Fan Relay, Thermostat and flush the coolant and then change the Coolant Sensor if the problem was still there. That easily would have been $600-$800. Morons.
Hope that this helps someone.
TO CHECK TO SEE IF BOTH AUXILIARY FANS ARE WORKING DO THIS TEST:
Step 1 - With the car off, insert key and turn ignition to the second position where the lights are lit up on the dash.
Step 2 - Press and hold both "Auto" buttons on the Climate Control unit for approx. 10 seconds and then let go (Try it again at 15 seconds if this test does not work the first time with 10 seconds).
- Both Black Auxiliary Fans should turn on and spin.
If only one fan spins, you may have a problem with the fan itself, the fan relay or a circuit to the fan. The chances that both fans do not spin during this test is very slim as both fans should not break around the same time.
The issue that I had was that the Driver's side Auxiliary Fan was shot and did not spin during the test. The Passenger side auxiliary fan was spinning. So, I swaped out the driver's side fan and viola. Fixed - spins. Comes on at approx. 103 cel and shuts off at 98 cel.
Another tip if your car starts to overheat while driving is to manually turn on the fans by doing Step 2 above while driving - this can save your engine/head gasket. My stealership thought that it was the viscous fan clutch and recommended that I change that, the Fan Relay, Thermostat and flush the coolant and then change the Coolant Sensor if the problem was still there. That easily would have been $600-$800. Morons.
Hope that this helps someone.
Last edited by newguy2008; Jul 10, 2009 at 01:41 AM.
