This sprung up about a month ago before I realized what was happening. Coolant level dropping, needle almost went up to last line on H a couple of times. Losing about half a gallon of coolant every 200-300 miles.

It’s still too hot outside to take the whole dashboard off to get to it (if that’s what it involves). I’m almost tempted to go with a really good stop leak or hose by-pass route.

Anyone done this job before?

Does your carpet get wet? I would check that out first to confirm. I also would never use any kind of stop leak unless you really don't care about the car. Loop the lines if you don't want to deal with it now.

...just checked today: the carpet is wet all the way to the back seat. This is devastating and disappointing considering I just bought new front struts. But at least it’s not the head gasket as previously feared.

I’m tempted to use stop leak as it seems some products sound good lol. I don’t want to cut the heat because coming into October, I may need it.

It’s discouraging to be having a new problem every other month it seems. The car is mostly reliable and has gotten me an extra 60,000 miles in the last 2 years, but dammit I just wish these unplanned repairs would stop! Lol. In May it was the A/C project, In July it was the fan clutch, August the broken spark plug (not really the car’s fault though), now in September the heater core lol.

Absolute NO on the stop-leak. I can go into more detail, but if you need an explanation, you probably won't care to hear my opposition to it.

Loop the lines. You can live without a heater core.

You bought a $50k car for probably next to nothing, and have gotten a lot of good use out of it. It's not a Corolla, it's gonna have issues as it ages.

I did the hose bypass of my heater core. Not because of a heater core leak, but because one or more of my blend door motors failed and the heat would not activate. I figured that I might as well stop the coolant flow through the core since I could not use the heat anyway. The bypass project is easy, but working at the firewall right in the middle of the engine compartment is a bit of a pain in the back.

AZhitman wrote: ↑

Wed Sep 18, 2019 3:52 pm

Absolute NO on the stop-leak. I can go into more detail, but if you need an explanation, you probably won't care to hear my opposition to it.

Loop the lines. You can live without a heater core.

You bought a $50k car for probably next to nothing, and have gotten a lot of good use out of it. It's not a Corolla, it's gonna have issues as it ags.

Unfortunently, I’ve already bought 2 bottles of stop leak from 2 different companies lol. But it’s not the stuff that you see sitting on the shelves, I spent 2 days researching stop leak stuff for cooling system/radiators in particular. I spent less than $20, and I plan to only use half of each bottle. One I’ve never seen on the shelves, but both are more like stuff that supposedly the car manufactures use for routine and new engines. Neither has visible particles and both claim to not clog heater cores. They cure with heat and air. After I week, I may just go ahead and drain some out. But my radiator drain plug is cemented in (stupid plastic screw stripped, so have to remove a hose instead), so maybe I won’t lol.

I’m going this route because i rather try it first before sinking time into a new core. I looked at the FSM, and I’ve pretty much already dissembled the whole dashboard already (replaced cabin filter, radio, clockspring, the little light behind the speedometer). So honestly, it’s not going to be too hard for me to remove the dash.

For me it’s just more of the time and the fact I’m in the middle of having struts installed AND have to get a new windshield AND register my vehicle. It’s too much and it’s depressing. I made good money these past couple months, but I’m sinking it into my car (all planned, and cant go to work without the car).

Based on the reviews and careful consideration, and looking at lots of stop leak products/claims/reviews...I’m hoping the ones I get will work, assuming it’s a small leak or breach in the seals. Also my heat blows super hot (especially when it starts to run hot from low coolant), so at least it’s not clogged I know that much. I think the constant potholes and vibration, or possibly my pressure going up from summer stop and go might have caused something to crack.

my12by60 wrote: ↑

Thu Sep 19, 2019 8:51 am

I did the hose bypass of my heater core. Not because of a heater core leak, but because one or more of my blend door motors failed and the heat would not activate. I figured that I might as well stop the coolant flow through the core since I could not use the heat anyway. The bypass project is easy, but working at the firewall right in the middle of the engine compartment is a bit of a pain in the back.

Dude, I’ve had that same problem! It’s honestly a fairly easy, but kinda tight to reach part. The air mix door is up near the foot pedal, no dashboard disassembly required. However, I was only able to order that part from Infiniti websites. $79 though wasn’t bad.

However, driving without heat isn’t an option (unless it’s possible to get some heat to the car without the heater core, and just using engine air??

After I first bought the car in Arizona, I had to drive to Tennessee in January. There were times it got down to 18 degrees in some spots. With the windows up, heavy coat and gloves, I still almost got frostbite. My feet and hands were the coldest, and it got so bad my feet and hands got numb. It was MISERABLE. It was so cold and at that time I really didn’t know (or care) how to fix the heater.

So yeah, if the stop leak doesn’t work...I’m just going to have to take 2 or 3 days and just pull the core myself lol (I know that defeats the purpose of asking for advice lol). However, I may have to do the by pass method if not...because it’s almost been too hot to work on the interior of a car. I sweated like a gallon just taking the glove compartment off.

Do you have a link to the part for the air mix door? Is it one of those little rectangular motors?

There's gotta be some way of getting sealant into the core without also circulating it throughout the entire cooling system.

First off, you bought a 21 year old, limited production, luxury car and you are expecting it to be like owning a Buick Century. Even worse that most of the car does not share parts with any other Nissan/Infiniti, it's going to be more expensive and involved to fix. If you are concerned about putting more money into the vehicle then you are making a poor decision with the stop leak. Anything that will seal cracks or holes WILL also be able to clog and seal coolant jackets or at the very least, contract them. Either do it right or cut your losses and pick up something cheaper to run.

Yeah, if something cracked, the SL won't fix it.

I've been doing this for a loooooong time and have never known anything in a bottle to fix something. Ever. If it did, we'd be hawking it here on the site.

I get the frustration, but I can't argue with slick marketing and shady snake oil sales tactics. All I can do is explain the way a car is built, and if a hose or fitting is cracked (99% likely), SL won't fix that, period.

Then you've got funk in your entire cooling system, including your thermostat (bye bye jigglevalve).

Basically, what I'm saying is this: If you're trying to save yourself some work, that's fine - but once you go down that road, there's no "I'll do it right later." It's easier to fix it right the first time.

Besides, if it's too hot to work on the car now, wait a month.

Also, no, there's no way to have heat in a car without the heater core. Bypass the hoses, buy a cheap electric heater (plugs into your cigarette lighter) and get your $20 back from the snake oil salesman.

Update: so yesterday i pulled up the carpet via cutting it down the center and removing. Pretty much passenger back seat floor was flooded. So yeah, must have been 2-4 gallons of coolant dumped under my carpet.

And no the stop leak didn’t work. But figured it was worth a try.

I wasn’t trying to complain, it’s just that it’s becoming a dilemma of whether I want to continue fixing things or give it up. Problem with giving it up, all the fixes I made this year (all 4 shocks, a/c, all 4 belts, fan clutch) would essentially be a waste of money I spent. And with my finances, I would simply just be getting into another used car with more problems down the line.

I understand cars are not without their maintenance needs. It’s natural. But I try to tell my friends, it’s not as simple as trading it in and being done with it. I rather keep it and then at some point it will be my 2nd car, like how right now my Maxima is my 2nd car.

When I first got this car, NOTHING was working right. But I figured as long as the sunroof and all electrical connections worked right, and there was no “ghetto mods”, I could handle it. I spent about 2 or 3 months on storage getting it together, and then it was ready to go on it’s first 1,800 mile trip. I had 0 problems.


I don’t mind fixing things and understand quick fixes aren’t the answer, but I don’t want to be spending money Infinitely if it’s going to have to be one after the next. BUT I am confident after this, there shouldn’t be anything else major needing to be done except maybe a windshield and a rear control arm. Non of which are urgent.

Air mix door link: https://www.infinitipartsdeal.com/parts ... it,,27733N

By the way: I decided to just go ahead and do the job myself. It just seems silly to junk a car over a $29 heater core. Especially considering I just put in over $900 and got a new tag and title with inspections test passed.

f*** my friends and all their suggestions to get a new car! Lol. If they want to have car payments, by all means. Atleast with my repairs they don’t come with late fees, interest, and threats of repos lol. People need to stop trying to make suggestions without financing the option to do so. My car will be back on the road in no time.

THAT'S more like it.

I was just about to bust on you for saying how easy the dash is to remove (bleh!) and then not wanting to replace the heater core.

Keep us posted - Car payments are for suckas and fools.

98_Q45 wrote: ↑

Wed Sep 25, 2019 7:14 am

By the way: I decided to just go ahead and do the job myself. It just seems silly to junk a car over a $29 heater core.

Not sure I'd trust any heater core that only costs 29 bucks - particularly since replacing it again would be an all-day job.

$29 , ?? Intersting point, being IN the car - kinda like using sch. 20 sewer lines in your million-dollar house ??

Skibane wrote: ↑

Thu Sep 26, 2019 4:16 pm

98_Q45 wrote: ↑

Wed Sep 25, 2019 7:14 am

By the way: I decided to just go ahead and do the job myself. It just seems silly to junk a car over a $29 heater core.

Not sure I'd trust any heater core that only costs 29 bucks - particularly since replacing it again would be an all-day job.

Lol, they don’t get much more expensive than $29. I actually I found it on amazon, free shipping. Spectra premium. I could have gotten one for $18 on rock auto, but I seen some bad reviews on that one. The one I got is the same one as sold at Napa for a little bit more. Most all auto stores have them for $60 or less. The Infiniti one is $230...considering I don’t need one that’s going to last another 21 years, figured it’s not worth it. Plus I’m BROKE. This shocks job was the most I’ve spent on this s*** since I brought it 2 years ago. $650 for struts, $300 for alignment and install. Too much damn money, but bad shocks I feel was the reason for the heater core breakage. I feel like saying f*** it and hopping on 1 of those electric pay as you go scooters lol.

But I’ve actually had good luck with “Internet” condensers, so I figure something similar and simple like a heater core should work out fine.

I almost considered filing a claim on my insurance company for new carpet. There was literally 2 inches of water when I pulled the carpet up. And driving around without the carpet, I can see how quickly the leak is accumulating. But with some wicked scrubbing and drying in the sun, it should be fine. The coolant did a good job of preventing rust and mold. But that foam material is probably going to take a week to fully dry...and that’s outside in the sun.

You're making good choices now.

And $29 is fine for a heater core. It's not a complex part. Hell, I have a $100 intercooler that's been in use for a decade, it's worth more as scrap aluminum.

I think it all depends on the car and your budget. I put a $20 Denso radiator from Amazon Warehouse Deals in our old G, and it made it several years before we sold the car. Much better to spend $29 on a heater core and keep your Q on the road than let her overheat, sit for a long time, or bury yourself in debt for a new car.

Q451990 wrote: ↑

Fri Sep 27, 2019 9:13 pm

I think it all depends on the car and your budget. I put a $20 Denso radiator from Amazon Warehouse Deals in our old G, and it made it several years before we sold the car. Much better to spend $29 on a heater core and keep your Q on the road than let her overheat, sit for a long time, or bury yourself in debt for a new car.

Tell me about it! Most of my friends are into the whole new-ish leasing/car payment thing. I can understand having a reliable car, but I’ve seen people pay for a car 3 times thru interest, and STILL get repoed. Eventually at some point I’ll get tired of fixing on cars, but my career situation just isn’t profitable enough at the moment to take on such risk. At the same time, this back to back car trouble is becoming a problem for my sales job, and the frustration with it is adding to the frustration of an already frustrating job lol. Hopefully after this, no more problems for awhile.

Anyhow: so I started the project. But only got as far as removing the dashboard. I am at a loss for words to be honest. So many screws, electrical connections, almost afraid I may forget where something may go.

The service manual seems to say I need to remove the steering wheel to get the dashboard far enough out the way. I don’t have a steering wheel puller or know how. And I’m looking at the heating unit kind of confused on how the hell to get to the heater core. So now, I’m just trying not to panic lol.

My best advice is to take a lot of pictures! In terms of the steering wheel, you can probably get by without a puller. On my truck, and my mom's Xterra, I was able to remove them without one. On those vehicles, I was able to just remove the air bag, unplug everything, remove the bolt, and gently rock the steering wheel forward and backward to loosen it.

I’ll have to try that. Considering my mechanic had the clockspring off a couple times already, it shouldn’t be factory tight anyway. I just thought needed the tool in order to remove. I have the airbag torx already though.

Kinda pissed because I was literally right there, dashboard off, all the switches around the steering wheel off. Had a plan to lift and drop, but wasn’t enough space. Had to put some of the stuff back on because I was running out of daylight. I got stuck on the dashboard pull part because the fabric on the door frame pillars was stuck in between the windshield, likely from a previous install. Wasted an hour trying to figure out why the dashboard wasn’t coming out.

Why not just drop the column? I think it's like two bolts mid way and two nuts lower down.

Update: I wish I never started this job. I should have quit when I was ahead. I got the steering wheel off and the whole dashboard...only to get to the heater unit at be at a loss. The heater core was no where in sight, and it looked like I would have to remove the a/c evap box and intake unit. Wasn’t happening! Removed 4 bolts around it, then looks like it would have been multiple doors, motors, etc.

I ended up just aborting mission, and now in the painstaking process of putting everything back. Never had to abort a project before, certainly not this far in. But during the process I started to get so frustrated, I figured I didn’t want to have to do any further. I wanted to cry midway thru, and I’m a big man lol. Just far too much disassembling for such a simple part. Too much time wasted, and I really didn’t like having to disassemble my whole interior. There should have been a heater core access door right where the hoses connect to the firewall.

I should have known the service manual was tricking me into doing this by not including how to remove the heater box. At this point now, I plan to maybe try to flush the cooling system/heater core and add more stop leak, or just do the by pass all together.

I don’t even think Infiniti themselves would do this hideous project. They woulda more than likely rather just recommends me to buy a new Q50! Lol.

Welcome to cars. You will have even more fun when you have to do a heater core in a vehicle that requires both front doors and windshield removed to pull the dash.

MowgliCSM wrote: ↑

Tue Oct 01, 2019 7:12 pm

Welcome to cars. You will have even more fun when you have to do a heater core in a vehicle that requires both front doors and windshield removed to pull the dash.

Thats why stop leak products are so attractive! Lol.

I almost had a meltdown trying to put the dashboard back on. So damn heavy, didn’t want to scratch any door panels. Fortunately what made this a little easier is the passenger seat was already removed due to the flood. So I had a lot of space to work with.

I was starting to wonder if I could pull the entire heater up and out, but I didn’t want to have to pull anymore bolts out. I was just over it, the whole idea of by-passing and having a portable heater was starting to sound too attractive.

I’m going to try 1 last ditch effort to completely flush the heater core directly, and another stop leak formula. If anything, it was a good learning experience. Atleast now I know how to swap a steering wheel. Next time I come across a salvaged i30t with the wood accented steering wheel, I’m grabbing it lol.

Wow. That's a lot of work invested to walk away now. Any thoughts on calling it beer-o-clock, and looking at it with fresh eyes tomorrow?

Q451990 wrote: ↑

Tue Oct 01, 2019 9:19 pm

Wow. That's a lot of work invested to walk away now. Any thoughts on calling it beer-o-clock, and looking at it with fresh eyes tomorrow?

I thought about it, but I’ve already put most of everything back together lol.

I just couldn’t do it. I just have too many other stressful things going on, and don’t have the mental capacity to handle it all at once. Not to mention, my 2nd car has a bad alternator. On top of that I’m trying to move to a new city, and work on my other business...so only half of my brain was working to do this right now.

I had tried removing 4 bolts around the heater unit, it wasn’t budging. I figured moving it would probably mess up some of the air mix/fresh air door positions and then I’d be stuck trying to figure that out.

I still haven’t actually heard of anyone successfully finishinf this project though, even looking at past threads about it back from mid 2000s lol.

Update: heater core is officially dead:

Over the last couple days, I ran a Prestone flush and cleaner. The leak got like 20X worst! I expected it to clean the system and probably leak more, but at one point the coolant was gushing from under the dashboard and quickly flooded the floor (again, no carpet so I can see what’s going on).

Once I finished the flush procedure, I was attempting to add stop leak directly to the heater core hoses. Well that failed because the plastic or whatever s*** it’s made of, top hose leading inside the heater core snapped off like cardboard when it was wet. Once it dried, it re-hardened, but I had to quickly find a by-pass hose to fix it.

I couldn’t find any Infiniti specific heater hoses. Found one that had the longer/shorter ends, and it fits (a 3/4”), but it almost kinks at the U part. It’s just a generic gates hose. So far it’s worked, but I’m concerned about the slight kinking at the U. The hose just wasn’t curved sharp enough to meet the hose points exactly. Hoping it doesn’t blow.

I’m devastated and relieved at the same time. I can finally put my car back together without worrying about coolant leak. The stop leak was working, but I have no idea what’s going on. Maybe at some point the cardboard hose would have separated, so it’s good that I found out now rather than later.

But also bummed I will now have no heat and no way to cool the engine down if I start running hot. Kudos for having an airplane propeller in the engine though.

Update: I will never use stop leak for coolant again lol. Oil maybe, but not coolant.

Somehow the stop leak I used gummed up my system to where the gunk kept settling into my expansion tank. This caused either the coolant to barely able to push thru to the expansion tank, making my radiator cap spray all over, AND it caused it to be unable to return the coolant to the radiator, leaving me with a completely full expansion tank, and not enough coolant returning to the radiator. Which was causing the temperature gauge to go up.

Fortunately i figured it out soon enough to where now I’ve just been emptying the recovery tank every 400-500 miles or so (just did a 800 mile trip). I already drained radiator once and it still won’t go away. Can’t do it again because each time I’m taking the hose off as my drain c*** is sealed due to being stripped. And I’m out of town. Each time, I’m finding sandy funk settled at the bottom of the expansion tank. It could be the fault of mixing 2 stop leaks at separate times (I did k seal earlier this year for an unknown loss of coolant, and switched to a different product for the heater core issue...which likely could have been the same problem both times).

Yeah I feel like a dummy. But when you’re desperate and coolant is pouring under your floorboard, you’re willing to try anything. Hoping soon the problems just go away lol. Infiniti is not unreliable by any means.

Update:

So now that winter is officially here, I’ve been able to get real life results from driving with heater core bypassed.

BRUTAL!! Lol. Endured an entire week of below freezing temperatures and I can say it’s far worse than not having a/c. I’ve had both. No a/c in Florida and no heat in 13 degree weather. I can create cool air with sunroof and windows down, not having any way to warm up is downright dangerous. And the little electrical cigarette lighter heater did absolutely no justice at all. Only serves as a handwarmer and window defroster. So now I’m looking back at replacing the unit again.

But I’m stuck: because it’s the plastic pipes that were faulty (which turned into some leaky cork material after 20 years), I’m forced to have to order direct from the dealer or online dealer. $233 is lowest I can find. f*** ridiculous!

And after all that...now my water pump is leaking...but I’ve already got the part ordered and repair is on the way.

Anyone know of any way to find the plastic pipe by itself? I don’t want to risk a junkyard part failing because all the work involved. I’m going to call around to more Infiniti places tomorrow and see. The local one claims they can’t sell the plastic piece separately. But I just can’t justify spending $200+ on a factory heater core when there’s plenty for under $50 and I’ve already dumped enough money into it already.

Infiniti needs to be a bit more flexible with their parts on this one! They’ve discontinued more and more parts, I’ve already had to order the whole damn strut/spindle kit for $600. Why the f*** can’t I just get a plastic pipe connection. I’ll even pay a ridiculous markup for it. If anything, that should be replaced considering making it out of plastic was a bad decision considering the labor involved. But why make me buy the whole core