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Old chestnut but my 944 Turbo will not start. Help please.
https://forums.tipec.net/viewtopic.php?f=25&t=21737		 Page 1 of 1
Author:  Jonnyporsche [ Mon Aug 01, 2016 9:53 pm ]
Post subject:  Old chestnut but my 944 Turbo will not start. Help please.
The story so far. It started with, after running for a short distance after starting, the engine would cut out totally, not a cough or a splutter just dead, all other electrics working fine, leave a minute or two and it starts fine and runs with no problems. I suspected the DME relay so replaced it with a nice new one, still did it. Now it won't start at all except on the odd occasion it will fire but then die after a few seconds, suggestions already made are FPR and Crank sensors. I have replaced the FPR, still no start and following Clarks Garage I have tested the crank sensors with a multi-meter, (electrics are a dark art to me) these are the readings.

Image Image Image
Image

I think I've got the decimal point in the wrong place but you get the idea.
Any help with trying to sort this out would help please.
Author:  u63af [ Tue Aug 02, 2016 7:44 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
Hi
Have you checked your fuel pressure or that you getting consistent fuel?
Author:  Jonnyporsche [ Wed Aug 03, 2016 9:46 am ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
u63af wrote:
Hi
Have you checked your fuel pressure or that you getting consistent fuel?


No I haven't, unfortunately I don't have a fuel pressure test gauge.
Author:  944-Scott [ Wed Aug 03, 2016 8:02 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
I'd say its not fuel if its not spluttering when it dies. I cant help you with the electrical results of the crank sensor but I can tell you that the symptoms you are having are the same as what I had on another vehicle which had a crank sensor problem.
Author:  u63af [ Wed Aug 03, 2016 8:18 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
May well not be fuel but first thing I would always check on any car not starting is if it's getting fuel or a spark. Just take the fuel line off at injector rail or fpr and put hose in bowl and see if any fuel come through, then you at least rule out if you are getting fuel. Only takes minutes. Making sure no fuel has been spilt, then take an ignition lead off and hold a spare plug against a point of engine to earth it and see if you are getting a spark. Have you checked your ignition leads, rotor cap and arm?
Author:  Jonnyporsche [ Wed Aug 03, 2016 9:43 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
Quote:
Have you checked your ignition leads, rotor cap and arm?


All replaced earlier this year.
Thanks for all suggestions, keep them coming please.
Author:  AlpineTurbo [ Thu Aug 04, 2016 2:48 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
Did you say your car started and then cut out straight away?

If so I'd be looking at the AFM, but also the wiring to it.
Author:  scam75 [ Thu Aug 04, 2016 3:59 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
+1 for AFM. There is a bend in the loom on a turbo where it bends back to plug into the AFM. This is a known weak link. Also the connectors on the loom or on the AFM itself may need a wee clean up. I used DeOxit for this a few years back and it worked a treat. It could also be your AFM. I have a brand new turbo AFM if it turns out you need one.

Stuart
Author:  flt505 [ Thu Aug 04, 2016 7:33 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
Fuel blockage/gremlin between the filter and the injectors? Could the fuel pump itself be compromised by something in the system?

Dave
CT
Author:  Jonnyporsche [ Thu Aug 04, 2016 9:19 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
scam75 wrote:
+1 for AFM. There is a bend in the loom on a turbo where it bends back to plug into the AFM. This is a known weak link. Also the connectors on the loom or on the AFM itself may need a wee clean up. I used DeOxit for this a few years back and it worked a treat. It could also be your AFM. I have a brand new turbo AFM if it turns out you need one.

Stuart
AlpineTurbo wrote:
Did you say your car started and then cut out straight away?

If so I'd be looking at the AFM, but also the wiring to it.


Thank for that one scam75 and AlpineTurbo, will check out the wiring and connector ,I have also checked out Clarks for guidance on testing the AFM, I'm also replacing the crank senors wether that's the problem or not as there is nothing in the cars history as to how old they are, jobs for tomorrow. Also ordered a fuel pressure test kit, any excuse to add to my workshop tools :D
Author:  944-Scott [ Fri Aug 05, 2016 5:58 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
Quote:
Also ordered a fuel pressure test kit, any excuse to add to my workshop tools :D


Lol I tell myself the same thing.
Author:  Jonnyporsche [ Fri Aug 05, 2016 8:16 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
So bad to worse. :( How am I going to get the broken off part of a crank sensor out of here? not a good day today and I've still got the other one to replace :( :( :(
Image
Author:  u63af [ Sat Aug 06, 2016 5:32 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
I had issues on my old turbo with them not coming out, does the whole mount not come off with both sensors in it?
See attached shows close up pics

http://www.pelicanparts.com/techarticle ... cement.htm
Author:  Jonnyporsche [ Sun Aug 07, 2016 9:20 pm ]
Post subject:  Re: Old chestnut but my 944 Turbo will not start. Help pleas
u63af wrote:
I had issues on my old turbo with them not coming out, does the whole mount not come off with both sensors in it?
See attached shows close up pics

http://www.pelicanparts.com/techarticle ... cement.htm


As I understand it the mount cannot be removed with the sensors in place.
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