924Board.org

dorian · Joined: 27 Nov 2012 Posts: 2 Location: san francisco, ca

Hi everyone. Please excuse my lacking acumen - I'm not an expert.

Over the weekend I decided to test my luck with my '78 924 on a 500-mile trip. Made it almost halfway there when the car suddenly began losing power steadily from a 65 or 70 mph cruise on the freeway. I shut it off immediately at gas station to find coolant leaking pretty good from the overflow (on top of coolant tank), but apparently from nowhere else. The leak stopped after a few minutes.

I topped off coolant and got back on the road for the remaining 15 miles or so of the trip, during which I had no further power problems, but when I got off hwy and made it to destination, the car was making fun new clanking sounds & an occasional high-pitched whirl sound at idle. It was also dumping coolant again when I reached my final destination and started it the next morning and of course sounded real unhealthy still.

Engine temp gauge never read hot at any time - must be broken obviously, as I assume we're talking about an engine overheat, although what I thought odd was that immediately after the incident, there was no steam or signs otherwise of excessive heat under hood, and there was no pressure when I removed coolant cap. I've had the car since June with no issues like this, and I've done one long trip previously.

Thoughts?

Thanks so much,

-dorian
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'78 924 - manual

Smoothie · Posted: Tue Nov 27, 2012 11:21 am Post subject:

Possible suspects -
The water pump. They'll often make a clanking sound when they go south. Sometimes also leak through a "weep hole" at front below the shaft when they go - though you say it isn't leaking anywhere other than the cap..

Fairly obvious, but make sure all the belts are still there and in good condition/tight.

Cooling system needs to be bled properly- else an air pocket can form near the sensor, causing inaccurate readings.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

jazz guy · Joined: 26 Nov 2002 Posts: 434 Location: Colorado

Good advice ^. Other possibilities: thermostat not opening fully, partially blocked radiator. How often does your 924 get driven?

Hopefully it's not a blown headgasket over-pressurizing the cooling system. Check the dipstick and the underside of the oil filler cap for milky oil/crud accumulation which can be a sign of headgasket trouble.

SMOOTHIE!!!! it's great to see you popping up on the board! I was afraid you'd moved on; sold the Porsche and bought a Prius or something.

!tom · Posted: Tue Nov 27, 2012 4:03 pm Post subject:

Could also be a leaking expansion tank in addition to the other failures.

Glad to see the Smoothster lives!
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78 924 NA
5-lug

dorian · Joined: 27 Nov 2012 Posts: 2 Location: san francisco, ca

Since June I've been driving the car only on weekends for the most part and not very far each time. The only other long trip she's been on was when I picked her up from the seller in san diego and drove from there to los angeles and from there to san francisco the next day.

During that epic maiden voyage, I made sure to keep the rpm's as low as possible throughout (probably no more than 60 mph the whole way), because of course I was convinced I wouldn't make it. But I did - no engine problems.

I guess I got overconfident this last time. There was awhile there toward the end where I was cruising at 80+ mph.

I just hope I didn't burn her up; love that little car.
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'78 924 - manual