Menu toggle

My 930 Got Very Hot Then Stalled

930T

930T

New member
Hello All

This is only my 2nd or 3rd post but I wanted to pick some brains if possible.

Don't know if you went to Silverstone at the weekend? If you did you may have got caught up in the queuing traffic to get into the circuit? I got to the circuit around 8.45am then spent over an hour queuing to get in, whilst queuing I left my engine running and it gently got hotter and hotter until it then stalled and wouldn't restart....at all. I had to be recovered home.

The car ran great for the 160mile trip to the circuit, no issues at all. Once queuing the temp gauge started off on the lower white mark and made it up to just above the upper white mark, but not into the red section before the engine stalled, tickover was fine, not lumpy etc. I have been looking into the reasons why it just stopped, and the Bosch CDi seems to be a popular culprit. I haven't had chance to do any testing yet, only got the car back last night. CMG, the Silverstone recovery people are excellent by the way, full marks to them for a great service.

The reason for the post though was to check that this is how all aircooled 911's behave when idling i.e does the temp gauge just keeps increasing.

Any help would be great. Thanks Craig.
 
Craig,

I was alos at Silverstone and the queue to get in at 9.30 was very long. My oil temp got to the last white line and remained there. No other issues.
Have read on other forums if the coil is a Bosch unit not made in Germany they can leak externally, perhaps as you have pointed out a good place to start.

Does the car start when its cold?

Good luck
Tim.

 
Hi, not sure if this helps at all... but my 1987 3.2 got very hot when trying to get into Classic Le Mans 2 years ago. While the engine didn't cut out - it got very hot and started to smoke quite a bit (which it never did before then).

Eventually I got the car into the car park - let it cool over night. The next day, a little smoke, eventually clearing over the next week or so. Car was then fine...

Hope you get same luck...

Gary
 
Craig,

I'd be interested to know if the car starts fine now from cold and runs as normal? I didn't have quite as much waiting around at Silverstone parade, however carried on down to Paris afterwards. Car drove fantastically well and was ok on temperature guage. After a 3 hour drive in some pretty intense heat from Calais, I parked up outside the hotel and then 10 minutes the car wouldn't restart. A few hours later it fired up fine from cold. After some investigative work it sounds like it could be the fuel accumulator, part of the Bosch K-Jetronic system. If yours stalled and didn't restart, I just thought that if it starts and runs fine now, this may be the same issue?!?

Cheers,
Martin
 
Thanks for the information Gents. I tried the car about 3 or 4 times during the day, swapped fuel pump relays around, fiddled with as many wires as I could but no joy, even when cold. When the breakdown people arrived they checked around with a meter and found no voltage to the coil. It may be coincidence, but reading around it seems that heat can affect the Bosch Spark Box (CDi) in the Turbo, I think the 3.2 Carrera's use a different ignition system. The info I was particularly interested in was the continually increasing oil temp. As Tim's seems to stop increasing at the upper white mark then maybe my oil 'stat is also not working correctly? It's booked in at my specialist at the start of September so maybe I should get them to take a look at that too! Gary, do you remember how far your needle rose up the oil temp gauge when your car got hot?

Thanks. Craig.
 
Martin, the fuel accumulator is on the list for items to check. I have bought a spark tester, so that should tell me straight away of it's fuel or ignition causing the issue.

Thanks. Craig.
 
Craig,
I was in the same queue at Silverstone with my 930 and the oil temperature gauge went quickly to just above the top white mark and then stayed there, I assume because the front oil cooler fan was doing its job inside the drivers side front wing. That's what's happened previously when touring the car in South of France and Spain in very hot weather.
I agree with others check the CDI box, never had mine fail but it is a known weakness.
Peter
 
In case anyone is interested the problem was with my Spark Box (Bosch CDi Unit). I found a contact for repairing the original unit as follows:

http://www.911-hkz.de/

Google can translate the page if required.

The Engineer is Lutz Gerberding, and he seems extremely knowledgeable about these and other units associated with our cars. Lutz speaks good English if you want to email etc.

After looking at my spark box he emailed me as follows:

"your cdi-unit has been repaired and will be shipped back today.

The ignition capacitor (that holds the 400V ignition energy) was defective with a shortcut. The shortcut has blown several other components, that deliver the 400V high voltage.

There are 3 major reasons for a problem like this:

1. Usage of a newer ignition coil type Bosch 0221121001 with silver housing, Made in Brazil , charge number 908 on the bottom side. Use the Made in Germany historic original instead (black housing) or use BERU ZS-109 (without a resistor in series).
2. Burned noise suppression resistors (spark plug connectors, distributor finger, plugs on the distributor cap, plug on the ignition coil). The resistance of this components should not exceed 6000 Ohm, each.
3. Any other breaks in the secondary ignition system, like broken ignition cords, loose spark plug connectors, "¦

In all these cases the ignition energy can´t flow over the spark plug and hits back into the cdi-unit instead. After this has happened a few times, the ignition capacitor will fail.

So the repaired cdi-unit comes with an integrated overvoltage suppressor, but this only protects the cdi unit and doesn´t solve the problem.

If you can´t find any reason that was responsible for the problem, don´t worry to use the repaired cdi-unit. Then watch out for any sparks on the top of the ignition coil (don´t touch anything). If you can notice sparks, the problem is still not solved."

He returned the unit to me in 2days, cost Euro260. Well recommended.
 
Very useful info Craig..... sounds as if you got decent service and good advice at a sensible price.
I'll never forget being told 10 years ago that to replace the spark box on my 3.0 930 was going to cost me £1650! Fortunately Permatune helped me out - and then I found that problem was being caused by a single broken wire.
I know that there are several people in the UK who can repair CDI units, but you can never locate them when you need one in a hurry!
 
We had a 930 do this at an event recently, it got hot and died. Was fine once everything had cooled down though.

My own car, a 3.2, has never had the temp gauge higher than just below the second white line, despite extreme provocation. It hasn't always ended well though, the starter motor gave up the first time it got that hot.
 
You must log in or register to reply here.

Posts made and opinions expressed are those of the individual forum members

Use of the Forum is subject to the Terms and Conditions

Disclaimer

The opinions expressed on this site are not necessarily those of the Club, who shall have no liability in respect of them or the accuracy of the content. The Club assumes no responsibility for any effects arising from errors or omissions.

Porsche Club Great Britain gives no warranties, guarantees or assurances and makes no representations or recommendations regarding any goods or services advertised on this site. It is the responsibility of visitors to satisfy themselves that goods and/or services supplied by any advertiser are bona fide and in no instance can the Porsche Club Great Britain be held responsible.

When responding to advertisements please ensure that you satisfy yourself of any applicable call charges on numbers not prefixed by usual "landline" STD Codes. Information can be obtained from the operator or the white pages. Before giving out ANY information regarding cars, or any other items for sale, please satisfy yourself that any potential purchaser is bona fide.

Directors of the Board of Porsche Club GB, Club Office Staff, Register Secretaries and Regional Organisers are often requested by Club members to provide information on matters connected with their cars and other matters referred to in the Club Rules. Such information, advice and assistance provided by such persons is given in good faith and is based on the personal experience and knowledge of the individual concerned.

Neither Porsche Club GB, nor any of the aforementioned, shall be under any liability in respect of any such information, advice or assistance given to members. Members are advised to consult qualified specialists for information, advice and assistance on matters connected with their cars at all times.

Porsche
Lockton
Pirelli
Officially approved
Oracle Finance
WEX Esso
Collecting Cars
Back
Top