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2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion


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bradkunz
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Oct 11, 2016, 9:35 PM

Post #1 of 22 (845 views)
2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Sorry for the long subject. I own a 2005 Infiniti G35 with close to 100,000 miles. A couple of months ago I noticed that I was starting to overheat and immediately pulled over. Since then, I have had "professionals" put in a new dual fan radiator ($400), new T-stat and coolant reservoir tank ($300), new catalytic convertors on both the driver's and passenger's sides ($850), and all new spark plugs and 3 coils which I was told were failing. For a little history, my cousin lives a few hours away but is a certified mechanic at a large local dealership.....he put the new plugs on, the coils, and cat's and said it passed a compression test for the motor and a pressure test on the cooling system (and didn't charge me since we're family). Every day for the last 10 days, once the motor gets warm, for the first 10 miles of driving I see the temperature gauge going up....today was the first time I actually got nervous as it was really pushing the HOT zone. After I drive it for 10 miles it levels out. At the same time I am having trouble getting the heater to work, which I assume is connected to the problem?? Need advice please. Like I said, I have a new t-stat, which seems to be what everybody online blames this on. Could this be connected to a water pump problem? Thank you VERY MUCH in advance for any advice!


Tom Greenleaf
Ultimate Carjunky / Moderator
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Oct 12, 2016, 1:33 AM

Post #2 of 22 (829 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

That's a lot of stuff done and checked and still doing it for "professionals" as you said.


1st thing comes to mind is it isn't properly full of coolant. That can be a lot of reasons by itself. That would explain the fast spike towards overheat and heater not working so well alone.


The behavior of low coolant is thermostat, sensors are not fast to respond to actual temps with bubbles or vapor as they would with liquid. Blaming thermostats IMO is over done most of the time if correct ones used and installed most are fine.


It overheated to begin with and serous issues like a head gasket problem haven't been really ruled out. Compression test isn't going to show that so easily unless totally obvious and many are not.


Weak water pump as in corroded impellers? IDK - comes on slower than this but on the list.


Have to suggest another visit and more bucks and quit the guessing. Rule things OUT like head gasket(s) and vapor/air still in the system. No guessing, vacuum fill this car (don't expect you to 100% understand - techs should) but may be the only way to totally know if more vapor/air found after known filled you in fact get real serious about head gaskets.


Unfortunately they are too common and one overheat enough. They can be erratic and elusive so can't rush blaming this on that.


Why the converters? Fine if this is both burning coolant and putting exhaust/combustion gasses into cooling system which is a hunch right now it would probably throw codes they aren't performing at proper efficiency doesn't always mean just toss them.


You seem to have help but also think missing the source problem.


BTW - The blaming thermostat thing just bugs me. Sorry but if professionals are saying this it doesn't come across as very professional! You can test a thermostat is opening on time with an infrared thermometer for a strong clue.


I can't see the large picture of all this. Perhaps just too many cooks in this kitchen and one with enough time allowed plus explain what was found to your satisfaction is the way to go. You've invested already so suggest if car is good in general finish this off and be in shape for a good long time,


T



bradkunz
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Oct 12, 2016, 3:58 AM

Post #3 of 22 (827 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Thank you for the quick response Tom! Very much appreciated. I will check the coolant again this morning, but the last time I checked, it was at the proper level.

The 1st mechanic to try to correct the problem (the one who put the radiator in) claimed that there was no head gasket leak, but the more and more that I spoke to the gentleman the less I believed he was a professional.

When I made the 3 hour drive to my mechanic cousin a few weeks ago the car went from "purring"....to sounding like a "Harley" on the trip. My cousin said that I certainly had a problem in the exhaust system. We drilled a hole in one of the catalytic converters and a lot of debris came out. He "thought" swapping these clogged converters would fix the car's sound and fix the overheating at the same time. It has certainly helped the car sound better ("purrs" again), but still have this feeling that one day very soon I will be pulling over on the busy interstate.

Would obviously rather nip this in the bud now. Thanks again for your advice. Like you said, I've put so much money into this vehicle over the past couple of months that it seems stupid to not finish the job!


Tom Greenleaf
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Oct 12, 2016, 4:22 AM

Post #4 of 22 (823 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Were "radiator" fans replaced or the radiator or all - they aren't one thing.


Head gaskets can be elusive - behave when checked so I (if going to blame that) want as much proof as possible as it is involve but then again done with it as a lurking something.


Checking coolant level at a tank doesn't mean the engine and radiator are in fact full - that's the problem. Many cars don't have a cap on radiators (don't ask me which ones do or don't I just look) and harder to fill up to near impossible.


Since converters were messed up with debris no less there's really is something going on. If just rusted bits from pipes and flex pipe in front it really should have warned you with a check engine light longer ago I would think.


Note: Used/spent converters are worth some serious bucks - have cousin check on that if not already cashed in.


What you can maybe do is when totally cold before first start squeeze upper radiator hose while looking at the new recovery tank. If that bubble air you have air or vapor.


Vapor meaning gasses from weak/blown gaskets (heads) can blow vapor back into cooling system which acts as air and doesn't cool engine well then quit maybe if warmed up. You might also note that an upper hose from a stone cold start pressures up fast. In a minute not a few or more is too fast that's gasses not expansion from heat as it hasn't had time.


This aggravation takes some time along with other evidence to blame the real problem then choose how far to go.


You decide. At about this age and miles it's buying yourself a dependable car again or good money after bad. Hard to know and decide - personal choice or a gamble on your part.


In short - it's not hard to miss something by real techs that have no ill motive. Takes time and if it doesn't misbehave in front of them in time allowed or available could easily think it's all done but clearly more is wrong.


Job now is what part you can do and convey the info on giving time for a tech to nail this down. Say if I'm wrong - you aren't about to tear engine apart if in fact it is a whole head gasket job are you?


The tech at hand needs your observations IMO that they might not see or witness.


BTW - heater not producing expected heat is either debris not flushed out with the radiator changed or thermostat or vapor mixed in.


Sorry for the novel. Vapor doesn't exchange heat well. Example: You can swoosh your hand in an oven that's 350F cooking for a second but just 200F coolant would peel off all skin in a second - heat transfer isn't near the same liquid vs vapor be that air or combustion gasses,


T



bradkunz
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Oct 12, 2016, 6:51 AM

Post #5 of 22 (813 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Once again Tom, I am certainly very grateful for you taking time out of your day to try to help me with my problems! Speaks a lot about you....(sorry this will be a long post to answer all of your questions)

The radiator and fans, complete package were replaced about 500 miles ago.

I never did mention that I did have an engine light come on prior to the car getting "loud" and now with the new converters my cousin was able to get the engine light off and it has not come back on again. I apologize for failing to mention that previously. The debris in the old ones appeared to be bits of rust as you mentioned.

If I were to need to rip the motor apart for a new head gasket I would certainly not go through that, send the car to auction, and make a new investment. The vehicle has always ran so well, and I've put so much money into it in the last couple of months that I'm trying to save it. Exterior is still in mint condition. The company that I work for is providing me with a company vehicle in the next couple of days, so this will ultimately be the vehicle my wife and son use and I don't want them to get stranded!

Ironically, I drove the 15 miles to work this morning, traffic was bad so there was a lot of idling time, and the temperature gauge did not move at all once the car was warmed-up (big contrast compared to the ride home from work last night!) It feels like it's "hit" or "miss"....a lot of times the temp rises in the first 10-15 minutes of driving and then out of the blue it is perfect just like this morning's ride.

When I mentioned that I checked the coolant level I did mean that I removed the radiator cap when the vehicle was cold and the fluid level was good. It was good again this morning, along with the coolant reservoir being exactly at the "MAX" line.

I did not know that you could squeeze the upper radiator hose and check for an air leak, so I will try that sometime this morning after the car cools down. GREAT idea!

If there was a head gasket leak, would it be visible to the naked eye (ie. fluid under car) or not necessarily? It sounds like they can be tricky to spot, but I have not seen any kind of fluid leaks under the car.

Thanks again Tom! Have a great day!

Brad Kunz
Iowa


Tom Greenleaf
Ultimate Carjunky / Moderator
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Oct 12, 2016, 7:45 AM

Post #6 of 22 (809 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

OK - Getting a better idea of situation now. Didn't mention codes as you said professionals who would have been using them anyway I would hope? If not, why not?
So, today it behaved all day? Was it much cooler outside or much warmer this time? I ask as most vehicles would force fans on with A/C or defroster/defog use so if conditions all different that's a good clue.


I'm still stuck on heater performance all with this recent work? However with ambient temps you may not have needed it or not sure how that plays in just yet.


BTW - I'm west of Boston so somewhat similar wild temp changes. Already a freeze here at night and in the 80s later. Seems silly using both in the same day but it's normal Spring and Fall.
**************************
So, I take it coolant in the reservoir is at the full mark when cold? OK if so there should be room to go over that without a problem but you should note tank must be marked for "FULL" (cold) and again a mark "FULL" (hot) is common and pretty much that's the common expected amount of EXPANSION of all liquid not some compensation for air.


FYI: Idea is liquid expands and extra is sent to the recovery tank from the bottom. Then when it cools down coolant shrinks again, air if minor would be bubbled up to top so it draws back from the bottom always which is liquid such that many if system is tight would eventually self purge out all air but know some just will NOT!
Wild extremes as below zero F. and above 100F with use can find it normally past those marks up or down accordingly. When totally too full or air pushing at recovery tank or boiling it will blow that out to ground and you've past either being too full by accident or boiling isn't allowed so finding out why is critical.


Head gaskets: Know that they can leak any which way or thing they seal which is oil in coolant, coolant in oil, coolant to outside, oil to outside, coolant into exhaust the common white smoke that never ends or this adding combustion gasses a little or a lot which you may not see anything but have symptoms of it to me isn't uncommon to find that problem with some time to prove that must be it.


Seeing air in system isn't realistic. Seeing bubbles when squeezing a hose coming up into a reservoir more than once when work just done isn't normal - never. Blaming any of this on exactly a head gasket issue isn't fast and easy many time. Other things can imitate same symptoms to be ruled out.


OK - so another car is coming so expenses on this one kept to your limits which is always your call. Knowing what and how much more to have a great car again includes some luck and guessing. Do know that new, used, real old, high miles (not this) or not anything that moves can quit running by surprise and without warning. That Murphy guy was right "At the worst possible time and place as well" he knew something we all don't!


*******************
Brad: Know this about this particular site. I'm done with this as any biz so have time. All regulars here are volunteers with no force to be here or how much time to spend at all. I don't mind and not here all the time nor take a device with me to check the place but not usually gone that long. Just points out there's no motivation to steer you wrong nor a motive to make a dime doing this. I'm totally sorry for plenty of typos and words misunderstood can work both ways too. Dang notebook PC changes spelling on my and I don't notice and all that thrown in too. Sorry about any confusion and do bring it up if not clear. No joy in even volunteering and being wrong for you.


So - still back to who has a scanner and can pin this down for you to at least know with some certainty what the heck it will take to end this? That you need to find the right person with both the tools and experience and the TIME is a key factor. Some folks will ask and I've done it many times - swap cars or just leave the car with a tech to use for a day so they have it from cold start thru when this might happen and ready to do checks right then and there. That you need to do by agreement with a willing tech and shop situation. With this if with what you've said already I would make that offer to you when in biz if it took two days NOT to be wrong and really see this happen. In the mean time you keep getting told a thermostat and if it pleases you and them let them do another but you must know that person or shop can fill it properly first before you get this car back,


Tom



Hammer Time
Ultimate Carjunky / Moderator
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Oct 12, 2016, 10:11 AM

Post #7 of 22 (803 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Boy, can you two guys type!!!!......................LOL



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
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Oct 12, 2016, 10:37 AM

Post #8 of 22 (799 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

I finally got new glasses and now embarrassed at how bad I was!
Off to get a deal on a Samsung computer so the fire will heat the house this Winter and still get my money back for the dang thing! Bad joke, Tom


bradkunz
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Oct 12, 2016, 3:46 PM

Post #9 of 22 (793 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Sorry HammerTime! It takes a lot of words to describe my situation....it certainly helps though that I can type about 150 words per minute! HA!


Discretesignals
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Oct 12, 2016, 3:53 PM

Post #10 of 22 (788 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Ya, don't read this thread if your sitting on the toilet. Your legs will go numb.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.


bradkunz
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Oct 12, 2016, 4:45 PM

Post #11 of 22 (782 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Thanks again Tom, I think you have me on the right track! So when the car's engine light first came on we were on the 3 hour drive to my cousins in Northwest Iowa (we are in Des Moines).....I dropped the car off....picked it up 1-1/2 weeks later (with new coils, new plugs, and new cat's) and the engine light was off. I didn't ask him specifically which codes popped up on the scanner, but he cleared it and it has not come back on.

So here is how today went:

Going TO Work: Should have been 15 min drive, but traffic was bad so it took 45 min...NO ISSUE

Lunchtime: Drove 5 miles roughly....NO ISSUE

Coming Home FROM Work: 15 minute drive with minimal traffic......NO ISSUE

When I say NO ISSUE, I mean, the temp gauge sat just below the halfway mark and never moved, so it seemed like the cooling system was working properly.

In each scenario, however, my heater would only pump out hot air if I was going about 60 mph on the interstate or faster. While idling.....heater was blowing cold air.

I researched this quite a bit today, and what I have gathered from my readings online, it seems like I have 1 of 3 issues (I've ruled the t-stat out because it was just replaced):

1. Heater Core Malfunctioning
2. Air in Cooling System
3. Bad Head Gasket

Do you agree with this in your professional opinion? I did read that it's "somewhat" simple to burp the air out of the cooling system. I have worked on my prior vehicles....replaced serpentine belts, starters, alternators, batteries, oil, etc. while I was growing up, so I'm a hands-on guy, but I always respect a professional opinion.

I know you said you don't do this for a profit, which I respect tremendously (you don't find very many people that will help people for free!), but I am the same way, and honestly, if you keep me down this path and your advice fixes my car, I promise you that I'll make you "for-profit" if you're willing to accept it! HA HA

In all seriousness though, I'm just trying to make sure the car doesn't overheat and will defrost the snow when the winter comes.

Thanks again Tom!


Discretesignals
Ultimate Carjunky / Moderator
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Oct 12, 2016, 4:48 PM

Post #12 of 22 (781 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

With the engine at full operating temperature and idling, feel the heater hoses at the firewall. Are they hot to the touch?





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.


Tom Greenleaf
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Oct 13, 2016, 1:20 AM

Post #13 of 22 (769 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Yes - if at this yourself just touch and feel temps and where is quite telling. That or a touchless thermo can end whether a t-stat is and really is possible still in the game. It's just not the most common to me as a solution or defective rather the first thing to be blamed.
Sorry I discounted that a bit firmly - it does happen just not often.


This problem just needs time to do and already said - rule things out with all info (code included with #s recorded if for future use) to zoom in on the actual cause(s) still at large IMO.


All of this is time, communication, understanding and choose whether if expensive what you will do as I see.


Please just take in stride some "banter" of good fun along the way in this thread. We are all over the US with different experiences ALL well qualified to find and fix this issue,


Tom



bradkunz
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Oct 13, 2016, 6:58 AM

Post #14 of 22 (760 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

I will check that today during lunch. Thanks for the guidance


bradkunz
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Oct 13, 2016, 6:59 AM

Post #15 of 22 (758 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Thanks again Tom. I will check some hose temps today after I let it get up to operating temp. It is cool this morning.....35 degrees in Iowa, but another trip to work this morning with no fluctuation in the temp gauge.


Tom Greenleaf
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Oct 13, 2016, 7:18 AM

Post #16 of 22 (755 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Same temps here - already killing frost for gardens but nice days. Only point is car is dealing with those temps now. All suggestions apply so far but at some level of cold weak systems don't show up the problem.


Some other things thought of to check.
* Force fans on usually can while cold by requesting defrost or request A/C one or both may come on or should on most. Feel without cutting you hands off if air is blowing towards the engine not out the grille! It can happen when fans changed out somehow - never to me but mentioned all the time.


* Once mentioned water pump's impellers impaired and can't pump enough. Oh boy. If you take care of coolant changes at all that's really rare or if never ran just water which is never suggested. IDK - to know for sure I think you'd about have to remove it and look and if there you'd be nuts not to put a new one in. I don't know of a way to be sure on that but heater hose temp check would be helpful to notice. Once warm if not air (that hard to be sure too) the smaller is the inlet and should be available engine temp coolant running thru it. Outlet may or may not be warm or almost as hot but not totally cold at all if other is hot.


Just FYI - long winded threads will end up with a page two. If you don't find a new post and somehow a notice doesn't send you right to it look for the "view all" words and click on that and whole thread will show, Tom (removing sign off as it takes up room)


bradkunz
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Oct 17, 2016, 6:53 AM

Post #17 of 22 (722 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Good morning Tom! Hope your weekend was good. I spent a little bit of time over the weekend trying to get to the root of my problem, and honestly, got nowhere! Ha Ha Every time I drive the car, if it has been sitting for quite awhile, the temp gauge goes up for about 3 or 4 minutes and then it's like something "clicks" and all of the sudden the temp gauge goes down, my heater works, etc.

I felt every hose I could find coming out of the radiator and motor and every hose I feel is warm/hot.

Once the car is warmed-up, been driven awhile (lto or from work) it doesn't have a problem anymore....but like I mentioned, if it sits in the parking lot (overnight, during work, etc.) then once you start going down the interstate the temperature gauge goes up quickly, sits there, and then a few minutes later it comes down. Puts me on the verge of a Heart Attack every morning! What could make my heater not work and my temp gauge go up, then all of the sudden, the heater works and the temp gauge goes down?

Thank you!


bradkunz
User

Oct 17, 2016, 6:55 AM

Post #18 of 22 (721 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

I did force the radiator fans on over the weekend by turning on the A/C and they are both working well, blowing a lot of air, and blowing in the proper direction....sorry, forgot to mention this.


Tom Greenleaf
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Oct 17, 2016, 7:12 AM

Post #19 of 22 (719 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

OK - the temp fluctuations can be normal and you somehow just noticed. Electric fan(s) can and are frequently waiting till a certain temp and either just come on or can increase speed and power of them


Heater should really always be close once warmed up. What A/C does is force fans to work but if way too cold might not - vehicle by vehicle design. You do NOT have to ask for cold air if you don't want super cold air at you just the least or warmest so called A/C request vs vent only or heat only or any "economy" setting.


Know your car. I can't know each.


System must hold pressure which is by a pressure cap! That totally matters a lot! The temps engines run at are above boiling points which would be bubbles without pressure.


Trivia: Water boils at 212F. It boils at 257F with 15lbs of pressure on it - exactly and stay liquid until that temp. Cars run normally between 212 and that 257F temp so a problem if it can't - why could be just a cap or anther problem to figure out why is the harder part to know for sure.


Just pay attention and try to know what is normal for now and what is not.


With fans known on temp on your gauge should be steady all the time and if not there's something to do or check probably already said that,


T



bradkunz
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Oct 17, 2016, 8:17 AM

Post #20 of 22 (717 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Please don't take offense to this Tom, but I have owned many vehicles. The way this vehicle is behaving is NOT normal! When you start a car in the morning, turn the heat up, and try to let it defrost the car, it should work. If I start this car up in the morning, let it run for 30 minutes, it will still not have heat. That is not how a car should operate! On top of that, when I drive down the interstate for a few minutes the temp gauge almost gets to the point where I need to pull over.....scares the crap out of me.

The simple question is: If my heater is not working properly, and my car's temp keeps going up (only when I am driving at a high speed, higher RPM), then "all of the sudden" the heater works and the temp gauge goes down, what could cause this?

Thank you Tom. Please do not take my post as being rude, I'm just pulling my hair out trying to figure this out? Heater Core???? Air in Coolant System??? What could it be? The hoses all feel Hot!


Hammer Time
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Oct 17, 2016, 8:48 AM

Post #21 of 22 (710 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

Sounds like you could have a t-stat sticking also.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
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Oct 17, 2016, 8:58 AM

Post #22 of 22 (709 views)
Re: 2005 Infiniti G35 - "Almost" Overheats for 1st 15 mins, then corrects itself. Heater NOT working well. Grateful for professional opinion Sign In

No offense either way - idea is trying to help and each understand each other. Great that you know this car and what to expect. I can't know 100% of what to expect on new car till owned a while nor everyone else's that might be totally normal - I don't think this is.
OK: I doubt the heater core. If it can ever blow heat it's not clogged almost a certainty. It's why it doesn't gradually warm up with the coolant passing thru it. Either a diverter door isn't allow flow or coolant is allowing flow till a certain temp or actually smacks of air in the system just not drastic enough to find in one quick check.


It probably is minor with major impact and is but can self correct if checked.


It's all of it working as designed at the same time and something isn't. Have listed some ideas is really best we can do without being there in person checking with equipment.


Both hoses being hot would be if coolant as a liquid is in there and would be stone cold or ambient temp outlet if vapor/air was passing thru. The clues are at hand.


Limited time for daytime hours today for me. If hoses are warm and heater is cold, temp in normal range it should blow heat. If not this could be more involved either a duct problem, flow of coolant problem or a feature being confused by some control and more.


It's hard. The or should say my process is rule out the common and obvious stuff first. This one is being erratic to me to peg down as only one possible reason.


Let me suggest getting a pressure check of cooling system and the kit that can do that also usually can check pressure caps. Cap when cold if you just wipe it and rinse it clean can't hurt.


Said - it's all of it. Faulty or erratic even new parts like a thermostat, erratic amounts of air or pressure irregularities on the list. The one nice to really believe can be ruled out is the dreaded head gasket thing. That's worth pegging this time as it would be a shame to blame that and be WRONG right off that bat.


So that's some stuff on the list to check what you can or have checked.


Not mentioned so far is there any chance this has WAY to strong of antifreeze? Can you check that yourself? Some plain tester with floating balls are fine for close to a buck sometimes.


Reason is if somehow this has close or is 100% concentrated antifreeze it's horrible at transferring heat by itself. It must be close to a 50/50 mix or a freeze protection that shows about -34F. Fine if up or down from that some but not maxed out on a protection level test or find out why.


That alone will almost always cause some problems but needs to be extreme like on purpose full strength is never suggested. It's so rare I didn't put that on the list either.


Have to go for now. Back later and other always welcome to chime in with their thoughts and things to do or check on this. For now you shouldn't let go of this till it's behaving properly as you know it can as damage for not finding this could be the result so find it even if not a web sight get help in person,


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