997 coolant

[v12v8]

Weird one. Doing 50mph, been driving for 90 mins so engine hot, oil reading just under 90c when coolant warning light comes on and water temperature jumps to 120c+. Pull over. Turn car off then on. All ok, warning disappears and coolant reading usual 80c. Drive another 30mins through traffic.

I stop for an hour or so at a meeting. Start car. Runs fine. Oil at 60c. Water temp rises to 80c and stays there. 3 mins later it jumps to 120c.

Get home. Take off coolant cap. No pressure. Put in 2l of coolant. Still not quite at minimum. No smell of coolant and no evidence of a leak. Not sure whether to keep filling until I reach the minimum??!

Bit flummoxed tbh. Any ideas? If oil temp had risen also I’d know the issue. But oil temp is fine.

It’s a 2011 997.2s PDK.

Cheers.

[anonymous-user]

2 litres? Are you sure no leak on the front (check pipes in wheel arch and rads)?

[v12v8]

I’ll check. Thanks.

[Digga]

There's a sort of plastic manifold thing, up near the front axle line on all 997's which is known to cause issues. It can fail and dump coolant very rapidly.

Here: http://www.911uk.com/viewtopic.php?t=122584&si...

[jonno_]

Any recent work that's relevant?

Sounded like an electrical or sensor issue till you found no pressure and added 2l.
The front crossover pipes usually weep slowly.
Maybe try water pump & bearings.

Edited by jonno_ on Friday 30th November 17:52

[v12v8]

It’s a stone through the central front rad. Assume odd temp behaviour was an air lock. Any case, new rad is £120 so ordered and should be fit in a week.

Thanks for all the replies. Appreciated.