2003 M45 Overheating while standing

Forum for Infiniti M35 and M45, and Nissan Fuga owners.
mipinc
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Car: M45

Re: 2003 M45 Overheating while standing

Postby mipinc » Mon May 31, 2010 8:51 pm

I tired the a new radiator cap but no luck. When I push the gas, the fan speed goes up and the temperature go back to normal. I tried this by pulling the cable in the TB. Only if the temperature stay below 80 f, I wouldn't havee to worry about this issue :confused:


myother45isalesbaer
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Car: 2004 M45 Q70 awd,4.5

Re: 2003 M45 Overheating while standing

Postby myother45isalesbaer » Tue Jun 01, 2010 9:37 am

Isn't the fan powered off the water pump? If so, what are are describing it could be water pump going.

I still question the tempature sending units on the engine. Not sure how many they are or where they are located.

I'm old school and not up on Infiniti's lastest ways. I'd try contacting Q45. He responded to you several posts back. He seems to have a wealth of knowledge and many techs he can tap into. Without actually seeing the car with a shop manual in hand I'm taking my best guesses.


mipinc wrote:I tired the a new radiator cap but no luck. When I push the gas, the fan speed goes up and the temperature go back to normal. I tried this by pulling the cable in the TB. Only if the temperature stay below 80 f, I wouldn't havee to worry about this issue :confused:

myother45isalesbaer
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Car: 2004 M45 Q70 awd,4.5

Re: 2003 M45 Overheating while standing

Postby myother45isalesbaer » Sat Jun 05, 2010 11:40 am

Did you get this resolved. I am very interested in what the problem was.

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UpStar
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Re: 2003 M45 Overheating while standing

Postby UpStar » Sun Jun 06, 2010 8:22 am

myother45isalesbaer wrote:Did you get this resolved. I am very interested in what the problem was.

Yeah..Im curious as well. It has to be something electrical at this point. Maybe the radiator fan unit device or possible one of those massive fuses under the hood on the left hand side. I had a similar issue with my old acura legend and it turned out to be the electrical unit that kicks the rad fan off/on. WASNT CHEAP!!! Hurry and get it looked at especially with this summer heat nearing. good luck amd keep us posted.

Q45tech
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Re: 2003 M45 Overheating while standing

Postby Q45tech » Sun Jun 06, 2010 11:28 am

Important to have test equipment that gives you an ACCURATE coolant temperature.
Like all Nissans the inside display is esentially worthless as it is not even close to linear.

IR temperature gun
Software that will display what the main ecu coolant temp sensor tells ecu.


As much as Nissan cheapen up things after 1997 and 2002. I'm still betting on 7+ year old radiator which might be clogged internally from abusive coolant changes [product or time interval].

Remember the radiator at best drops the coolant by 15-20F [inlet vs output].

The heat output from idle to cruise [2000 rpm] is an accurately known quanity for every 4.5 liter engine.Say 5 HP at idle [no ac] and 20 at cruise.

Take the entire system appart observe and test.

mipinc
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Car: M45

Re: 2003 M45 Overheating while standing

Postby mipinc » Mon Jun 07, 2010 1:25 am

In the last few days the temperature has not gone up to middel 80s where I see this problem. So far the temperature is staying in not namal range. I would agree on Nissan not displaying the correct information. My fuel level is messed-up like every one else but after couple of samll taps i goes back to normal level. The issue I see with the temperature is that it goes up and down much faster than the fule gauge so I am sure there is something gogin on radiator, fan, or something in the cooling system that brignthe temperatur down when the rpm is above 2000.

myother45isalesbaer
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Car: 2004 M45 Q70 awd,4.5

Re: 2003 M45 Overheating while standing

Postby myother45isalesbaer » Wed Jun 09, 2010 12:53 pm

Sounds to me like the coolant is not moving fast enough. When rev'ed up it cools down? I would suspect bad water pump or clogged up radiator. Don't trust the in car temp gauge. Those are very often way off. Did you ever check the sensing units on the motor? The temp gauge and gas gauge are really seperate issues realated to electonics.

If you think about it logically....what turns faster when you put RPM's on the motor. The water pump, which will force more coolant to circulate. If you have bad or restricted circulation through the radiator that will slow the coolant down. It will not get cooled down as it should.

Please let us know. We are very interested in the final solution.

mipinc wrote:In the last few days the temperature has not gone up to middel 80s where I see this problem. So far the temperature is staying in not namal range. I would agree on Nissan not displaying the correct information. My fuel level is messed-up like every one else but after couple of samll taps i goes back to normal level. The issue I see with the temperature is that it goes up and down much faster than the fule gauge so I am sure there is something gogin on radiator, fan, or something in the cooling system that brignthe temperatur down when the rpm is above 2000.

OPM45Owner
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Car: 2003 Infiniti M45

Re: 2003 M45 Overheating while standing

Postby OPM45Owner » Wed Jun 23, 2010 2:12 pm

Had the same problem of overheating, would return to normal once RPM went above 2000. Fushed radiator, still overheated. Changed Thermostat, still overheated. Spoke with two dealers who both said to clean the radiator and condencor that even a small amount of dirt could cause reduced airflow/overheating. Hosed down radiator and wiped down condensor. Car has not overheated since, have been running a week in 90 degrees and slow stop and go traffic. Mechanic still can't believe that that was the problem but it worked.

mipinc
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Car: M45

Re: 2003 M45 Overheating while standing

Postby mipinc » Thu Jun 24, 2010 6:46 pm

I have washed the radiator with no pressure and noticed black dirt lines in the water trail. Not sure if it was from radiator or engine cover. I will drive it tomorrow in the day to see if this also fix my problem. How did you wash the fan side of the radiator?

mipinc
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Re: 2003 M45 Overheating while standing

Postby mipinc » Fri Jun 25, 2010 1:18 pm

OPM45Owner, you are the man!! Good news!! The car is not overheating at all even after 10 minutes standing with AC on in 80+ temperature. I hosed down the radiator with notmlar waterflow from the from and the back through fan and behind the fan housing by removing the 2 screws on-top and sliding off one side at a time to get enough space to get the water in. I just can not belive that this could be this simple but it worked!!! Now time to work on the fule gauge issue for whcih i just put in the Chevron gas treatment to remove the sulfer on the fuel sending unit. I will keep you posted on that issue as well.

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Re: 2003 M45 Overheating while standing

Postby UpStar » Fri Jun 25, 2010 8:44 pm

Nice! :dblthumb: Lets hope it holds true. Good luck and glad you got some results.


OPM45Owner,

So radiator flush didnt work, but hosing down radiator and condesor did the trick? :confused: Im a little confused on the whole hosing down radiator and condesor concept, but whatever works.

Q45tech
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Re: 2003 M45 Overheating while standing

Postby Q45tech » Fri Jun 25, 2010 11:36 pm

Mercaptans [organic sulfur compounds] created in the refinining process can attack the printed circuit resistances in fuel level sender system. No easy solution other than entire sender replacement, if level accuracy is to be returned to brand new.

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TorontoM45
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Re: 2003 M45 Overheating while standing

Postby TorontoM45 » Wed Jul 07, 2010 7:02 am

hello Mipinc,
could you please tell me if i need to take out the radiator to hose it down? I have the exact same issue as you and im not really good when it comes to repairs and not much of a mechanic here. should i take it a mechanic shop or is it something i could do myself. thanks in advance.

nuge
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Car: Infiniti M45

Re: 2003 M45 Overheating while standing

Postby nuge » Thu Sep 06, 2012 7:32 am

I have the same issue. Where is the condesor located inside the engine bay?

7414
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Re: 2003 M45 Overheating while standing

Postby 7414 » Tue May 14, 2013 11:57 pm

mipinc wrote:I have washed the radiator with no pressure and noticed black dirt lines in the water trail. Not sure if it was from radiator or engine cover. I will drive it tomorrow in the day to see if this also fix my problem. How did you wash the fan side of the radiator?


I'm kind of late but can you go a little into detail as to what you diid to clean the radiator, thanks

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Re: 2003 M45 Overheating while standing

Postby Larz » Wed May 15, 2013 2:26 am

This may help explain why the temp gauge shows so high. I recently had my cooling system serviced at the dealer - they flushed out the old fluid, did some kind of treatment to it, and refilled it with new fluid. I got about 2 streets away from the dealer and the air condiitoner started blowing warm air and as I looked at the speedo, the temp gauge was completely at the top! I pulled off the road, switched the engine off and immediately called my service guy. There was no puddle of fluid under the car, no evidence of coolant in the engine bay, no odor of coolant, no steam coming off the engine, no evidence the car was actually overheating although it acted like it had. My service guy drove over to meet me, checked out the car, and he followed me back to the dealer. Turns out there was a pocket of steam in the system and they had to re-flush it to get rid of the pocket. It has run fine since then.

ThirdCoastBadBoy
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Re: 2003 M45 Overheating while standing

Postby ThirdCoastBadBoy » Wed Mar 10, 2021 2:52 pm

OPM45Owner wrote:
Wed Jun 23, 2010 2:12 pm
Had the same problem of overheating, would return to normal once RPM went above 2000. Fushed radiator, still overheated. Changed Thermostat, still overheated. Spoke with two dealers who both said to clean the radiator and condencor that even a small amount of dirt could cause reduced airflow/overheating. Hosed down radiator and wiped down condensor. Car has not overheated since, have been running a week in 90 degrees and slow stop and go traffic. Mechanic still can't believe that that was the problem but it worked.
I’ve been trying to figure this out for awhile now. I’ll try washing down the radiator and condenser today. I hope it works for me.

Dxta
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Re: 2003 M45 Overheating while standing

Postby Dxta » Wed Mar 17, 2021 9:22 pm

Reds12t wrote:
Thu May 27, 2010 5:02 pm
myother45isalesbaer wrote:Question....what is a hydraulic fan. I thought these were electric. Is it power by hydraulic pumps? I never heard of such a thing. Please explain. Are you just taking about a hydraulic clutch that kicks in as the heat goes up. This old dog needs and education on this one.
It is a strange set up for sure. These cars have a hydraulic pump that is built into the water pump, it drives a hydraulic motor that is attached to the fan shroud. There is also a small radiator mounted in front of the A/C condenser, you can see it through the grill. The hydraulic fluid reservoir is mounted on the drivers side cylinder head. If you take off the engine cover, you will see it, it is just the standard Nissan power steering reservoir.

Image

It is the brown reservoir in the bottom left of the picture. I ditched that whole set up for an electric fan, much simpler!
Please can you explain how you did the conversion of your hydraulic fan to the electric one here? Do you have pictures of some details to share? I have the same model of M45 2003 too.

Thanks


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