Porsche 911UK Forum

Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.

Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.

Intermittent Starting Fault

C2 TGA

New member
Joined
8 Jul 2017
Messages
1
My car has been suffering an intermittent electrical / starting fault over the last few years and it seems the mechanics at the local Porsche independent are unable to identify the problem.

I think it's time I tried a different tack, so I'm looking for recommendations for the best auto-electrician, based in South London (as that's where the car is right now), please.

The problem manifests itself when the engine is hot (i.e. above normal cruising hot). After the engine has been switched off for a few minutes (say, to refuel), the engine won't restart. The usual ignition / warning lights come on, but nothing happens when the key is turned to the start position. After allowing the engine to cool down for 15-30mins, it will start normally. Once started, the engine runs fine. Provided the engine doesn't get abnormally 'hot', the car will always fire first time, even if restarting.

The usual diagnosis is a faulty starter motor - that's what I was told this morning, until I pointed out the garage had fitted a brand new one last year (a few hundred miles ago), when I'd been told that they had found and fixed the problem!

An immobiliser issue (it's an aftermarket unit that otherwise works fine) could be another cause, or a dodgy contact / wire somewhere which opens up when the engine is hot.

Seems to be one of those hard to identify (i.e. no fault codes generated), intermittent faults that mechanics hate these days, and it might just be more profitable to turn the focus on the potential electrical issues than keep fitting new parts.

Thanks
 
Sounds to me like a classic DME relay issue. Have you tried a new one?

The is also another potential where the petrol can evaporate/run back when hot which has cropped up for a few Rennlist owners. Can't remember the fix for this but I thinks to do with the expansion tank :dont know:

ETA just read the fact it won't crank. In which case I'd say an earth strap problem on the starter motor and/or the one from then-be battery terminal to the body. Swap them both. Cheap as chips.
 
^^^^^^^^ what Zingari says sounds spot on.
 

New Threads

Forum statistics

Threads
124,353
Messages
1,439,439
Members
48,708
Latest member
JLav211
Back
Top