Has anyone used the Nissen heater core in their Mirage?

[Casey]

I've been driving my mirage a few years without heat with a bypassed core. It began leaking a few months after I bought the car used. It had been replaced once already under warranty by the original owner. I got tired of not having heat and bought a Nissen core since it had the different clamping style hoping it would be better. I took it to a dealer for replacement because the job seemed overwhelming for me. They say they can't get it to not leak at the fittings and want to put in an OEM core. Has anyone used the Nissen core and have advice?

[Johnny Mullet]

Not that familiar with the brand.I have done 4 Mirage heater core replacements here at my shop for friends and customers. Everyone of them bought them off RockAuto and they were the "Four Seasons"brand. No issues ever.

[Casey]

Thank you. I will try one of them and hope they don't charge me for doing the job twice.

[Top_Fuel]

Has anyone used the Nissen core and have advice?

You're talking about the heater core with the removable tubes...right?


There was a guy who just did one a couple of months ago. Actually...he used a Thermotec D65003TT (similar to the Nissens 707183). This guy also had trouble getting the tubes to seal properly. You can read his story in THIS thread.


Here is the side of the heater core where the tubes go into the heater box under the dash...




The guy who just installed that Thermotec heater core said the tubes probably would have fit easier (and sealed) if he had trimmed these 2 areas of plastic out of the way so the tubes could be positioned better...

[foama]

This heater core was successfully replaced with a

Thermotec D65003TT

heater core.


Here is the how to:

https://mirageforum.com/forum/showth...-core-with-pix

I did not use the Nissens branded core, but rather the cheaper Thermotec branded one. It works properly ever since.

NB: Some heater cores become plugged/restricted with a silicate-based goo. Nothing helps to get rid of it.
Other cores have become terribly plugged by a minute amount of lime scale. If simply flushed with lime scale remover, they can work again like new.

[Casey]

Thanks guys! For some reason I didn't get notified of these additional replies. Yes, it's the one like pictured above with the little screw clamps. They got it to stop leaking and so far so good. Really enjoying the heat. It's Florida but I surf in the mornings and it gets pretty cold. But about a week after the job I've been having issues. Every day or so while driving the throttle drops down to idle and won't do much else. I get code P2138. I have to coast off the road and shut it off, wait until it fully shuts down turn it back on and everything is fine. Doesn't seem to happen unless I'm driving at least 45 minutes. Google says the code is likely an error with the throttle position sensor. I'm not sure where that is but wondering if something could have got messed up from disassembling the pedal? I hate to go back to the dealer for service. they were really nice but it's over an hour a way. I'm gonna give them a call today.

[Top_Fuel]

...while driving the throttle drops down to idle and won't do much else. I get code P2138.

I just scanned the service manual for my 2015 and read about that code. It sounds like it's not throttle position sensor that's the issue...it's the accelerator pedal position sensor. If the ECM can't figure out how much you are pressing on the accelerator, it can't figure out how much to open the throttle plate...and your car defaults back to an idle. I assume when this happens, the check engine light immediately comes on?

I just copied this from the 2015 service manual. I didn't include the useless testing flowcharts they usually provide...I just gave you the text...

[Casey]

Yes, the check engine light comes on immediately. I shut off the car, turn it back on and everything works normally again and I clear the code. Once I didn't bother clearing the code and the check engine light went off on its own after awhile. I also have a rostra cruise control I installed almost two years ago which has never caused any problems before. I'm about to go poke around under there and see if anything seems amiss. Thanks for the reply!

[Top_Fuel]

If you can easily disconnect the Rostra from your pedal assembly, I would do that. Then clear the code and see if it comes back.

[Fummins]

I'm fairly sure the rostra setup has a piggyback harness that connects to the throttle pedal and possibly the obdII port as well. My previous car had that rostra cruise but I rarely used it.