M35 overheating in the weirdest way. Please help

Forum for Infiniti M35 and M45, and Nissan Fuga owners.
SeveLampley
Posts: 37
Joined: Tue Feb 18, 2020 8:04 am
Car: 2007 Infiniti M35-k23 silver, 5 stage paint correction, 2 ceramic coats, full bolt on, uprev tuned, d&s rotors, hawks hs1 pads, dot 5.1 steel lines

Post

Hello, I gotta 2007 Infiniti m35. I’m going to preface this by saying that it did this in the summer, but to a much lesser degree, I attribute that to the weather. Recently, the temperature outside has been dropping and this my first year with my M. Anyway, in April I put in a motorad thermostat Bc it was overheating to about 75% of the c—>h gauge (not counting the bonus space for H) it already had a motorad in it but I chose to still go with the one I had ordered (I now think that is what is going wrong) anyway, fast forward to now, I can’t drive anywhere without having the heat in full blast in order too keep the temp a little below half. I noticed something, completely different from anything I’ve seen. If I drive the hell out of it for a few seconds, that temp DROPS I mean if I gun it for 5 seconds it where it needs to be. So yesterday I put a new radiator in (didn’t cheap out on the radiator) And with the increased ability to cool, came overheating... I’m sick of this by now. I’ve bleed the system every way you can, still can’t drive two miles before the temp gets to ≈70% I’ve already ordered the OEM thermo stat (all of the parts stores sell the same motorad t-stat, just under their brand names) so I guess what I’m trying to say is am I barking up the wrong tree thinking it’s the t-stat or has anyone else had these problems, I love my M and have spent countless hours making it the most enjoyable car to drive as possible
—KEY POINTS—
-temp drops when I floor it (only if it’s above the “normal” temp
-upper hose seems to be under HIGH pressure after driving and it s hot
-Lower Hose is ambient temp(When overheating)
-I’m using conventional coolant (don’t have $ to burn if it’s gonna over heat anyway)
-new radiator yesterday
-new motorad thermostat in April AND today
-no signs of a blown head gasket
-no lights on the dash
-new radiator cap w the pressure release valve
-the fans seem to be working as they should (goes in to both speeds)
-temp seems to rise faster AND higher if the A/c is on
-High power sound system (Sony 600w 4 channel & kenwood 1000w, 2 kicker comp r 10s) Maybe something drawing power making the gauge go crazy?(I don’t think so but thought I’d put it out there)
I’m at a loss, anyone had this issue or hate that the only t-stat u can find in a pinch is f-ing motorad? :mad:


Costee
Posts: 336
Joined: Wed Oct 24, 2012 5:14 pm
Car: 2006 Infiniti M45 Sport
2012 Nissan Murano SL
Location: Lagos, Nigeria

Post

It seems more is involved here. I'd refer you to the FSM: EC99-102 (symptom chart), and EC 154-159. The bottom line is there is probably an issue with the IPDM, and maybe the ECM too.
Btw, you didn't mention whether the MIL (SES) light was lit.

SeveLampley
Posts: 37
Joined: Tue Feb 18, 2020 8:04 am
Car: 2007 Infiniti M35-k23 silver, 5 stage paint correction, 2 ceramic coats, full bolt on, uprev tuned, d&s rotors, hawks hs1 pads, dot 5.1 steel lines

Post

Costee wrote:
Sun Oct 04, 2020 6:47 am
It seems more is involved here. I'd refer you to the FSM: EC99-102 (symptom chart), and EC 154-159. The bottom line is there is probably an issue with the IPDM, and maybe the ECM too.
Btw, you didn't mention whether the MIL (SES) light was lit.
There are no lights at all and there never have been during my time of ownership

User avatar
telcoman
Posts: 5763
Joined: Sat Jul 08, 2006 11:30 am
Car: Tesla 2022 Model Y, 2016 Q70 Bye 2012 G37S 6 MT w Nav 94444 mi bye 2006 Infiniti G35 Sedan 6 MT @171796 mi.
Location: Central NJ

Post

SeveLampley wrote:
Sat Oct 03, 2020 10:59 pm
Hello, I gotta 2007 Infiniti m35. I’m going to preface this by saying that it did this in the summer, but to a much lesser degree, I attribute that to the weather. Recently, the temperature outside has been dropping and this my first year with my M. Anyway, in April I put in a motorad thermostat Bc it was overheating to about 75% of the c—>h gauge (not counting the bonus space for H) it already had a motorad in it but I chose to still go with the one I had ordered (I now think that is what is going wrong) anyway, fast forward to now, I can’t drive anywhere without having the heat in full blast in order too keep the temp a little below half. I noticed something, completely different from anything I’ve seen. If I drive the hell out of it for a few seconds, that temp DROPS I mean if I gun it for 5 seconds it where it needs to be. So yesterday I put a new radiator in (didn’t cheap out on the radiator) And with the increased ability to cool, came overheating... I’m sick of this by now. I’ve bleed the system every way you can, still can’t drive two miles before the temp gets to ≈70% I’ve already ordered the OEM thermo stat (all of the parts stores sell the same motorad t-stat, just under their brand names) so I guess what I’m trying to say is am I barking up the wrong tree thinking it’s the t-stat or has anyone else had these problems, I love my M and have spent countless hours making it the most enjoyable car to drive as possible
—KEY POINTS—
-temp drops when I floor it (only if it’s above the “normal” temp
-upper hose seems to be under HIGH pressure after driving and it s hot
-Lower Hose is ambient temp(When overheating)
-I’m using conventional coolant (don’t have $ to burn if it’s gonna over heat anyway)
-new radiator yesterday
-new motorad thermostat in April AND today
-no signs of a blown head gasket
-no lights on the dash
-new radiator cap w the pressure release valve
-the fans seem to be working as they should (goes in to both speeds)
-temp seems to rise faster AND higher if the A/c is on
-High power sound system (Sony 600w 4 channel & kenwood 1000w, 2 kicker comp r 10s) Maybe something drawing power making the gauge go crazy?(I don’t think so but thought I’d put it out there)
I’m at a loss, anyone had this issue or hate that the only t-stat u can find in a pinch is f-ing motorad? :mad:
Replace your thermostat with a OEM one from Infiniti.
Use the correct coolant as specified in the FSM/owners manual.
Use the correct OEM radiator cap for your vehicle. NO aftermarket cheap parts!
After replacing the required coolant, leave the radiator cap off as the vehicle warms up and observe and add coolant to the open radiator as necessary and observe any air bubbles coming out.
Once no more coolant is required, Do a pressure test on your cooling system.

EdBwoy
Moderator
Posts: 3507
Joined: Tue Dec 25, 2012 12:47 am
Location: Indiana, USA
Contact:

Post

Your description points to a coolant flow problem. And I will highlight that you should not go chasing the water pump - yet.

I will reiterate what has been said above. At minimum start with these:
1. OEM thermostat
2. OEM radiator cap
Working with a proper 50/50 coolant/distilled water mix would be a smart move too. Obviously, OEM is best, but there are options out there. should-you-use-blue-or-green-coolant-ye ... 22612.html

Costee
Posts: 336
Joined: Wed Oct 24, 2012 5:14 pm
Car: 2006 Infiniti M45 Sport
2012 Nissan Murano SL
Location: Lagos, Nigeria

Post

Remove the thermostat altogether and let's see whether you'll still experience overheating. If you do that rules out the thermostat as your culprit.

SeveLampley
Posts: 37
Joined: Tue Feb 18, 2020 8:04 am
Car: 2007 Infiniti M35-k23 silver, 5 stage paint correction, 2 ceramic coats, full bolt on, uprev tuned, d&s rotors, hawks hs1 pads, dot 5.1 steel lines

Post

Costee wrote:
Mon Oct 05, 2020 10:20 am
Remove the thermostat altogether and let's see whether you'll still experience overheating. If you do that rules out the thermostat as your culprit.
Put the OEM Thermostat in and, as I suspected, It’s perfect. I still have my same radiator cap (has a pressure relief valve, made bleeding the system a BREEZE) moral of the story OEM THERMOSTAT Under NO circumstance should ANYONE use an after market one. All of the part stores sell the same one, I’ve had three of them, ALL of them defective. So once again OEM THERMOSTAT please, for the love of god....

eyedeekay
Posts: 34
Joined: Tue May 21, 2019 6:14 pm
Car: 2006 Infiniti m35

Post

duplicate
Last edited by eyedeekay on Sat Jan 02, 2021 7:28 pm, edited 1 time in total.

eyedeekay
Posts: 34
Joined: Tue May 21, 2019 6:14 pm
Car: 2006 Infiniti m35

Post

SeveLampley wrote:
Sat Oct 10, 2020 1:26 pm
Costee wrote:
Mon Oct 05, 2020 10:20 am
Remove the thermostat altogether and let's see whether you'll still experience overheating. If you do that rules out the thermostat as your culprit.
Put the OEM Thermostat in and, as I suspected, It’s perfect. I still have my same radiator cap (has a pressure relief valve, made bleeding the system a BREEZE) moral of the story OEM THERMOSTAT Under NO circumstance should ANYONE use an after market one. All of the part stores sell the same one, I’ve had three of them, ALL of them defective. So once again OEM THERMOSTAT please, for the love of god....


Wished I found this thread earlier, I actually just replaced a MOTORAD thermostat with a second one LOL. Do you think this points to it being the thermostat in my case? The car runs pretty hot, the coolant ranges from 203 to 220 Degrees Fahrenheit and like in your case, the lower hose is strangely cold (my heater works however).

Also where did you find an OEM thermostat by chance, do you know if dealers even carry these in their warehouse, I would like to replace the thermostat asap. (Edit: buying one from z1)

edit: just saw the autozone reviews, and motorad has 2 stars with issues we are having. STAY AWAY. Also, I had to replace cooling fans because I think the MOTORAD thermostat overworked it to death, the new fans I got are always running nearly or at full blast.

Thanks

User avatar
VStar650CL
Technical Expert
Posts: 8294
Joined: Thu Nov 12, 2020 1:25 pm
Car: 2013 Nissan Altima 2.5 SL
2004 Nissan Altima 2.5 S

Post

Don't know if anyone has asked this, but did you put the bypass hole ("burp" hole) in the 'stat between 10 and 2 when you changed it? Sounds like the system is airbound. To bleed a 3.5 with a mis-located hole is difficult to impossible without standing the car on its arse.

eyedeekay
Posts: 34
Joined: Tue May 21, 2019 6:14 pm
Car: 2006 Infiniti m35

Post

Well for update, replaced the MOTORAD with an OEM thermostat and the car runs much cooler now. Also, the car is faster, apparently the ECM cuts ignition timing for every 5 degrees Fahrenheit increase after 200 Degrees Fahrenheit, and my car would run consistently around 207 and upwards to 223 Degrees. Now I run between 180-195 Degrees with AC on. Again thanks for the post, I would have been stump if you didn't share your results.


Return to “Infiniti M35 and M45 Forum”