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Well every so often at the moment the engine temp guage (OEM) is going rather high.

I recently did a clean out of sensor sender as guage was going erratic.

The elect. fan is working.

When air con. is on temp. goes up more.

 

Questions: Could it be due to the extreme hot weather conditions?

 

New exhausts were put on and I did notice that the idle rpm is slightly up - around 1 instead of below which could lead to overheating. When I noticed this I thought perhaps the ECU needs resetting - so undid battery etc. but the idle RPM may be still higher than should be - would ECU reset help redo idle?

 

Anyway the wife is out in the ZX at moment and I've told her to keep a check on the guages. She phoned in before to tell me that it h/guage was going up but with the air con off was alright.

 

Suggestions/ advice please. The last thing I want is a blown engine gasket problem or some other sh*t.

Thanks,

Geoff.

Featured Replies

and after fitting all that ICE, oh dear......

Have you checked the clutch on the engine fan, does temp rise whilst idling or on the move?

When was the coolant changed last?

;)

Thanks Johnny.

I've no idea about fan clutch.

It's rising on idle.

finally no idea when coolant was changed - would have to ask my mechanic.

Geoff.

Having just spoken to my wife - the temp goes up high when the air con is on.

So any ideas. The air con does add to rpm.

Geoff.

Well the wifes back with the car. Engine very hot. Coolant level ok same as when checked this morning.

When I switched it on temp. went to H and then started going down. Idle speed up again. So I reckon since getting new zorst idle speed needs resetting. Is this done through resetting ECU?

Comments and help appreciated.

Geoff.

Well I did more checks. TBS ok etc. Then let it idle for a while took it on a fast spin etc. Seems Ok now.

May be it's down to the extreme hot weather.

Geoff.

HI Tanzx,

 

my zed has been running hot since i got her a couple of months ago - i knew the air con was on its way out because an annoying ticking from the compressor, however i never connected the two things.

 

yesterday the compressor finally died and the zed has behaved herself beautifully ever since. i can only assume that the faulty compressor was putting an unduly high load on the engine. I'll see when i get it replaced.

 

Regards,

 

Alex

Idle will go up when the air con is turned on - there's a valve which lets more air in at idle to prevent the engine stalling due to the increased load of the compressor being on.

 

One thought, have you had a look behind the rad? Sometimes it can get full of crisp wrappers etc that it picks up through the front and this can block off airflow.

Thanks Andy, I recently fitted air induct. and so it was all cleared out thoroughly.

Finally last night I did check the TPS - disconnected it and it was absolutely in fine nick. After I reconnected it the idle was fine.

So either it was all down to the boiling hot weather which affected the ambiance. Or the new zorsts upset the ECU which was confused but relearnt.

Who knows. But I'll keep an eye on it.

Geoff.

As Andy confirmed the idle is increased when the aircon is running. On my car it's about 250-300 rpm more.

 

According to my Techtom the temp will increase by about 5 deg C on hot days. As the aircon rad is directly infront of the main rad, temp will also increase by up to about another 10 deg C when the aircon is running.

 

I have noticed that running a UK rad over a Jap spec rad brings temp down by approx 5 deg C.

The engine driven fan has a viscous slip coupling and a bi metallic spiral spring clutch that locks it up when needed. I've never had mine do this - Scotland only made 30c last week!

 

If it does lock up you should notice a lot of fan / air noise from the engine when you rev it. Could be also that it would still be locked up just after switching off.

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