Menu toggle

1979 Sc Targa - starting problems

Stevecaddick

Stevecaddick

PCGB Member
Member
I’ve a problem with starting on my 3.0 SC. It’s starts from cold first turn of the key, runs for approx 2 minutes then cuts out and cannot be restarted. Prior to this condition I was experiencing intermittent hot start issues. My local specialist found a slight leak on an injector line replaced it which seemed to solve the problem for a while. Now the car is completely un drivable. The last short outing on acceleration the car completely lost power and died, managed to bump start in 2nd and get it home. Not driven it since.
I was thinking fuel pump or check valve, discounted the fuel accumulator due to it starting ok from cold.

Any ideas?

Booked in with Cotswold Porsche in early April but ideally would like to progress it prior to then.
 

Attachments

  • IMG_4642.jpeg
    IMG_4642.jpeg
    653.7 KB · Views: 2
Hi Steve,

I am not sure if you are into diagnostics or just want a few ideas before you take your SC into the garage. Before you go down the fueling diagnostics route. I would double check to make sure you have a spark when the SC does not start. I had a broken track in my ignition box which would go open circuit when the car warmed up. I would think the car would carry on running rough rather than not start at all for fueling issues. I would pull off an ignition lead and connect to an old spark plug and put it against the engine for an earth connection to see the spark. When the engine stops working it would be worth pulling out a spark plug to see if it is very wet with fuel or the normal grey colour (i.e engine flooded).

I had a hot start issues on my SC but it would not stop running. Just would not start easily after being left a while. This turned out to be the fuel pump which leaked away the fuel pressure the fuel accumulator was trying to hold. The only way I could start the engine was the floor the throttle and crank the engine over for 10 seconds or so. I have seen fuel pumps struggle to work when they get hot which could be an issue.

The cold start injector pumps lots of fuel into the engine when cold so if you have a spark the engine usually starts. The control regulator has a bi-metallic strip which also allows more fuel as the engine warms up. I will put a few more thoughts together later in the week.

Rich
 
Thanks Rich. I was considering replacing the fuel pump but need to make sure I get the right one. The engine has been rebuilt to 204hp spec from its original 180hp. The problem has also worsened, it starts from cold first time but will only run for a minute or so before dying. When turning over after it’s cut out it’s trying to fire but just won’t catch even with the accelerator to the floor. Fuel pumps my first item to change I think. Then Lee at Cotswold Porsche maybe can find it.
 
No problem Steve. I have just got back from holiday. I am sure some fuel pressure testing at key points will solve your issue. I had some fuel issues on my SC when the petrol tank started to rust from the inside. Eventually some rust got into the fuel control warm up regulator which causes poor running. It would be interesting to know what fixes you issue.
 
Hi Rich, finally got home and got my issues with the car sorted with the assistance of Lee and the team at Cotswold Porsche. Actually quite simple and I missed it. Fuse supplying the fuel pump although intact and in place was loose and not making contact. This was intermittently cutting out the fuel pump and eventually stopped it running completely. Fortunately very simple, clean up and tighten the connections. A bit miffed that I missed it.
 
Hi Steve, Thanks for updating everyone with the diagnosis. It's great to know what the faults are. I have had the fuse screws work slightly loose before on my SC.
Shame you did not spot it.
Rich
 
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
Archant Dialogue
Back
Top