My N/A's auto trans started overheating the other day, so this morning I took it for a short run to warm it up & run the diagnostic. Trans overheats again in way less than 5Ks, run the diagnostic - no probs there. I can't tell what the trans fluid level is, it looks low to me but I poured 2 1/5 ltrs DX-III into it & no apparent change so maybe it's over full? Fluid is as clean as straight out of the bottle, no slipping, no grinding, just overheating. After wasting most of the rest of the day trawling through the forums looking for a clue I resigned myself to going to a mechanic to get the trans checked out & figured I'd change the engine oil myself to at least save myself that much dough. After the oil change, went for a short run (same route as the trans warm-up in the morning, roughly same ambient temperature) - no more trans overheat. WTF? Has anyone else: Experienced this or got any ideas what the cause & effect might be? OR Think I've probably still got trans problems that the oil change has somehow masked that need to be looked at more closely?
For the trans to overheat in 5km, there must have been a blockage to/or in the cooler. The blockage may have cleared itself.
Thanks Greg. I gather the stock AT cooler is prone to blockages & the preference is to bypass it with an aftermarket cooler. Got any preventative maintenance suggestions instead? I'm trying to keep it as near stock as I reasonably can but at the same time, I'd like to keep it running! :br:
Consider the age of your radiator, could well be the original side tanks containing the original trans cooler, therefore 20+year old. I'd hardly call that a weak point, just wear and tear.
to protect your tranny and keep it running, your best move is to install an external tranny oil cooler .... and to undertake regular tranny services as per manual. check out the PWR website .. they are QLD based and will sell direct to the public ... go for the largest tranny oil cooler you can.
Out of curiosity, what are you using to monitor your transmission's temperature? And is there any trans fluid leaking anywhere?
I know the Z's sensors often aren't necessarily all that crash hot but in this case the trans light wasn't lying. The trans was smoking when I popped the hood. There's definitely something leaking slowly but I don't think it's the trans.
Which trans light? I realize the below pic is for a TT but pretty sure the coloured warning lights are the same for your NA. ( big thanks to brisz for the pic )
In your picture it's labelled "Cat Overheat Light" but it's the Transmission Oil Temperature warning light.
Just so you know, thats your cat over temp light and not a good thing to have on, usualy caused by a misfire, commonly a broken coil pack connector, when at idle push them on and one will make a differnce and make the engine run smoother, but it will fall off again, usually replace all 6 while your at it. Along with smoke and over filled trans etc etc if it is not shaged already it would pay to fix it or get along to a Z experienced mechanic, by the sounds of it you cant afford not to. Give Eric a call at a2zed, on inspection he will be able to give you a good idea what the car needs. http://www.a2zed.com.au/?q=contactus
Picked up some connector sets from Baz not that long ago & replaced the coil pack plugs, applied dielectric grease & all so I doubt it's that, not running at all rough either. I've got time today so I'll check the resistance & timing. I haven't replaced the injector connectors yet so I'll have a crack at that too. It hasn't had an auto-trans service in the 6 months I've had & who knows how long before that it so I'm booked in for one on Tuesday anyway. Hopefully that'll cover all bases & sort it out, if not, I'll give Eric a call.
Started changing injector connectors but I've knackered something, cyl 1 is now not firing, doh! Timing is spot on & no error codes in trans or ecu diagnostic. Auto trans done today, no more warning lights, so hopefully that's the end of that, now on to my cylinder misfire next weekend.
Couldn't wait, one pin just wasn't quite in the plug. Thanks to everyone for the tips. Someone else will have to provide the hot dogs at the next tech day .
so your overheating of the auto tranny has not returned and all is clear ... ???? if so, top stuff ... !!!
Good to hear mate, I really appreciate it when folk take the trouble to post after getting closure on issues :thumbup: So, the original set of symptoms - I tried to join the dots on that but couldn't quite make a picture Was the transmission really overheating? Or was it a catalytic converter running too hot due to excess un-burnt fuel because of dodgy connectors somewhere else? Either way it's good that you got the transmission serviced. They're a tough old thing and they work great when they're up to scratch. Cheers
Connecting dots (hopefully) OK there was a warning light & burning smell & at one point later on, smoke, so I knew there was something wrong! Temperature gauge was in normal operating position so I knew it had to be something else. This: http://300zx-twinturbo.com/cgi-bin/manual.cgi?list=el&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=70&design=default&total=133 made me think the light I saw was the Transmission Oil light because I didn't really know anything else it could be. (Now I'm looking at the page again & realising that the Transmission Oil light indicator is only on European models, .) I didn't think it was a dodgy coil-pack connector because: a) I'd already replaced & greased them. b) Motor was not running at all rough I did start replacing injector connectors on Saturday but I only only got to do one: a) After replacement, that cylinder starting missing b) Another home project went pear-shaped (masonry job turned into a plumbing job but all good now). I've since had a transmission service done (needed doing anyway) and fixed my dodgy work on cyl 1 injector connector. So far no more Cat Overtemp warning light. Unfortunately, I don't see anything definitive as to what the original problem was or why it has gone away for now, only speculation: Car had a bad day & my over-filling transmission aggravated it until trans service (overflow might even have splashed onto cat? note that smoke only came after topping up trans) Dodgy connection somewhere that has righted itself just from my fiddling with connectors I'll keep working on the injector connectors + I picked up a set of needle files to go to town on the more specific connectors (TPS, PTU etc). I'll also keep in mind the external trans oil cooler but my next priority is getting air-con (read: de-mist!) working again (been raining here in Bris way too much).
