As I hardly ever post on here and am just one of those boring people who just read the forum, I thought I may as well get my money's worth today.

 

I have an overheating problem that only occurs in standing traffic. The car runs perfectly the rest of the time, no matter how hard you drive it. When I get to the fun motorway traffic jams, the Z has overheated on a few occasions.

 

The viscously coupled carrot dicer works fine. The electric fan works fine. There are no water leaks and the coolant is at the correct level. I'm presuming the thermostat works as I don't get any problems when driving the car fast.

 

The only time I get problems is when there is no forced airflow through the radiator, even though both fans appear to be working fine.

 

I do have a broken shroud above the carrot dicer. Is this likely to adversely affect the airflow enough to cause problems?

 

Cheers

 

Mike

Do you mean that it has boiled over? If you put antifreeze/summer coolant in the water, it'll raise the boiling point & therefore the car will be less likely to boil over.

Perhaps you should flush the system out with rad flush & fresh water.

Are you sure the VC fan is working? does it make a wooshing noise when you start the car from cold?

Also the cowling around the fan being missing won't help too much.

Hope one of the above mentioned items helps!

Check the Radiator cap - this can cause all sorts of problems and is a cheap fix...

 

CheerZ,

 

Andy

my 3000gsi used to do that and all it was, was there was loads of shit (dead leaves etc..) in the fins of the radiator what i did was got my vac and sucked it out then got my hose pipe been carful with my electrics and blasted it out and it was fide ever since that only used to do it in trafic jams and no other times

 

hope it helps

Sounds to me like the thermostat, it only does it when there is no airflow??

 

The rest of the time the air flow will keep the engine cooler, and hence not rise. I wouldnt trust the stock gauge, use a techtrom, and check the temperature with that.

 

You may be surprised under normal driving your temperature maybe above normal as well.

 

Leigh.

 

 

I had very similar problems a couple of months ago, which turned out to be the coolant temp sensor - the one that feeds the ECU with temp information(thanx everyone who suggested this to me).

 

This is the larger of the two temp sensors right at the front of the engine (other is temp guage sender) and is the left hand one as you look at them.

 

Try an ECU diagnostic. My betting is you have code 13, which means the ECU isn't getting a good signal from the temp sensor.

 

On my Z, this meant that on the motorway and stuff the car ran fine, but as soon as I came off the motorway into traffic, my temp would go ballistic, the coolant would boil and then all be released through the overflow valve. I then would have no coolant at all, which just makes the problem even worse, yet suspiciously the car would run fine next time.

 

I beleive what was happening was that after some motorway miles, the coolant was obviously hot. However, cos the temp sensor was duff, the ECU thought the engine was cold and therefore wasn't cooling the engine properly. Once in standing traffic, with no ram effect to keep the engine at temp, the coolant then got so hot it boils and discharges.

 

Temp sensor replaced (piss easy job), cost all of £22 from Nelson, and no more probs.

 

Hope this might help.

 

Steve

Definitly not the shroud. Mine was broken for 3 years (until I found out it was one of the cheaper parts to replace) and never got hot once.

I had the same problem. Try the rad cap, it caused me lots of grief even though it looked Ok. As soon as it was changed the problem went away.

Yup. If you dont pressurise you boil!

 

Also if you turn off the aircon in traffic as a temp measure you'll stop the heat dump to the condenser that then adds some heat to the main rad.

 

Mind you you might have crap, leaves and bugs in the fins too since the aircon condenser sits in front and spoils the view thru the main rad. Maybe hose it carefully from the engine side out the way. Not with a jetspray tho just a garden hose and be very very careful not to ding any fins!!!