hi there, i've just become the proud owner of a 94 uk zx; something I have been dreaming of for many years.

In general I have been driving round with a big stupid grin on my face for about seven weeks now.

In fact to only thing to wipe the smile away, is the lack of in-car heat at 5.30 in the morning; can anyone let me know if this is a common thing with the 300zx, or should I be looking to get it sorted.

cheers Nigel

The heater should work well, after the engine having been run for a few mins. If yours doesn't work at all then it could be that the fan or motorised vents have stopped working, or that the heater matrix has sprung a leak and someone has bypassed it - take a look down the back of the engine for suspicious looking water pipe mods.

motorized vents?

Could this be why I can get heat to my windscreen but not to side pods or front stereo panel vents?

thanks, mine's producing some heat and the vent are working fine: at least now that i know there's a problem i can investigate it. I'll start as you suggest by looking at the pipework.

cheers Nigel

If there's some heat then it hasn't been bypassed. This could actually be caused by a dodgy temperature sensor but I'm not sure which one the aircon control unit uses.

i think it uses the one in the bumper cos when mine was playin up reading all over the place on the ambient readout the temp wouldnt matter what i set to.

Nah it will only bring the heater on once the coolant is up to temp - I presume it uses the ecu temp sender rather than the one for the cluster. Is the auxiliary cooling fan on all the time?

HI Nigel

I was in the same situation as you last year, I too bought a 94 uk Z and also drove arround with a big grin, but this was more of a shivering, chattering of teeth grin on a cold morning. The symptoms were exactly the same with some heat but not enough to get me warm. The problem was the thermostat and when I replaced it with a new one the heater worked great. There has been a few posting in the past with people having to replace the thermostat due to this problem. The job of replacement is quite easy but if you are due a cam belt change then you may as well wait as it is easier to replace during this. If you are going to fit a new one yourself get a good hex wrench that fits on your socket set as I had to go out and buy one (after breaking 2 cheap ones) half way through the job. In total you are looking at about 2/3 hours.

Hope this helps

Cheers

Ady

Thanks Andy, i've been to busy at present to do any more than drive it; will hopefully try to 'flush' heat exchanger this weekend, if that doesn't work i'll try your suggestion; my motive's "always try the easiest option first". anyway fingers crossed.

cheers Nigel

Nigel

I did that first by taking off one of the hoses going into the heater matrix then removing the rad cap and pouring water into the hose you should see water flowing up out the top of the rad. This will confirm whether water is flowing or not.

Cheers

Ady