Porsche Enthusiasts Club Forum

Well the conclusion at the moment is that the dizzy cap bottom screw was out and water had creeped into dizzy. Also reference sensor leads had insulation gaps, so wrapped up and sprayed with damp start. All earths are new and sound and check all other connections, ECU, relays and fuse box etc that I can find and nothing a miss. Test drove today and all seemed fine but it wasn't that wet. Big test tomorrow at Silverstone GrandPrix track as the afternoon is going to be wet according to the weather forecast.

I don't have an Engine tray so wet from the road could be flicking up when its raining very heavy.

Fingers crossed

Hi,

Have you tried replacing the DME fuel relay? If it's slightly intermittent, it could be turning the fuel pump on/off momentarily.

I used to have a similar problem with my 944 cutting out in the wet intermittently. I replaced the DME relay and sprayed everything electrical in the engine bay with WD-40. Never had a problem after that.

Hope this helps, although it sounds like you might have found the fault from your postings.

Ben

Hi Ben, thanks for this tip. If it happens again I will investigate this relay.

Silverstone was very wet from 11.30 onwards but the car drove without issue. Also very wet on motorway on way home but no problems. Think the dizzy loose bottom screw was the problem.

thanks to everyone for all your help.

best

blacksuz

Glad you got it sorted.

glad to hear it was a simple fix

fingers crossed it stays that way

Hi scottish 944, my intermittent cutting out problem has appeared again but this time in the dry after driving all day on track. It feels like its slightly different problem this time but who knows as its so intermittent.

Do you still have the name of the electrician who fixed your problem with the sensors?

best

blacksuz

Hi all, thought it was worth letting everyone know what I have done to date on the car to stop the intermittent cutout fault. I still can't be sure that its fixed but it sure is running a lot better and the fuel consumption is up as well. BIG THANK YOU to PEANUT for his advice and support!

So what have I actually done since last post?

Test driven it over 600miles and a track day at Anglesey

• Cleaned up earths under fuse box and reconnected
• Remade earth from ECU to chassis as looked corroded
• Checked all earth braids to engine and bodywork
• Completely stripped and repaired O2 sensor wire that had melted between heat sink and bodywork
• Checked, cleaned contacts and re-seated all relevant connectors including ECU connections
• Checked sensors wiring where possible
• Removed radio and taped up bear wires that were left hanging and damaged behind radio

It is indeed running much better now and far smoother going up and down the rev range. Tick over is also very stable. It points to the o2 sensor wires which were actually melted to the chassis. However its not totally conculsive.

I am doomed of course as the fans are on permanently now, I guess this is the thermoswitch

Lets hope this post is now closed