Mechanics

CAR OVER HEATS NORMAL WHILE IN IDL

2000 Mercedes Benz ML430

Engine Cooling problem
2000 Mercedes Benz ML430 V8 All Wheel Drive Automatic 87 miles

Hi my car over heats normal when in idle or driving. I have replaced the radiator fans and the engine fan clutch. It has enough antifreeze and everything else. I think it started when my MAF went out and I replaced it with an aftermarket. But that didnt work out right either because the engine would not recognize it it would turn off the check engine light off but the car would over heat and the fuel to air mixture was way off that it even cracked my CAT converter. After I drove the car for a little bit with that MAF sensor the car would overheat and shut off. Then I bought a factory MAF and put it in the car ran great but the engine does not stay at normal temperature it just goes up and down. If I park somewhere and stay at idle for a minute the engine temp rises when I start driving it goes down and I cannot figure out what the problem is.
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Vladislav
January 9, 2009.




Do your radiator fans come on when the overheat occurs? Is the engine thermostat sticking?

Tiny
James W.
Jan 9, 2009.
No the fans do not come on when it over heats.

Tiny
Vladislav
Jan 11, 2009.
In the fuse block under the hood on the driver's side, check 30a fuse #44. This fuse feeds the fan relay for the cooling fans. If fuse is good, check the fan relay in the same location. Next, check 25a fuse #41 for the circulation pump and the relay next to it. Let me know what you find.
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Tiny
James W.
Jan 11, 2009.
2000 Mercedes-Benz ML430 over heating problem, I have changed the fan and pulley

Tiny
Dadesco@yahoo.com
Jun 20, 2012.
Start with a leak down test to confirm a head gasket

check the thermostat for proper operation.

The radiator could also be clogged as well.

Do not drive this until you have it repaired as you may damage the motor

Roy

ASEMaster6371
Jun 20, 2012.

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