how did you get on Rob ? have you got it starting again yet ?
Some closure on these non starting /running threads are always useful for others arriving here searching for a fix
| Porsche Enthusiasts Club Forum https://forums.tipec.net/ |
|
| 944 S2 fails to start :( https://forums.tipec.net/viewtopic.php?f=25&t=23023 |
Page 1 of 1 |
| Author: | robmal [ Thu Nov 02, 2017 3:36 pm ] |
| Post subject: | 944 S2 fails to start :( |
Hi all I have never had this problem in my ten years of ownership with this car, it has always reliably started except sometimes when hot (fuel check valve I am pretty sure) The car has been standing for two months, so I gave the battery a two day charge up as it can have some drain otherwise. This morning the engine turned over fine but no firing, not even an attempt. Fuel in the rail, but apparently no spark at the plugs. Replacing the DMA relay with a brand new spare I always have in the glovebox made no difference. Despite an horribly wet summer in Argyll inside the fuse/relay box is lovely and dry. A quick read at Clarks Garage online tells me that no tacho bounce means that one of the sensors is likely to be at fault. The tacho needle is deadly still when cranking. Does anything else spring to mind as an obvious potential thing to check, before I try to get an oscilloscope and look at their outputs? Cheers all |
|
| Author: | robmal [ Thu Nov 02, 2017 4:21 pm ] |
| Post subject: | Re: 944 S2 fails to start :( |
Further reading hereabouts tells me that the two sensors that a S2 has are a bit different than the two crank sensors on earlier 944... A S2 has a hall sensor on the front cam pulley to identify what stroke the engine is on. It is unlikely to prevent starting even if it has failed, but replacing it can improve performance. It also has a crank sensor counting revolutions of the flywheel (by a missing tooth) and if indeed mine has failed then this will be the one that will prevent spark. Faults can be wrong gap, failure of sensor or broken wiring. Hmmm |
|
| Author: | GlennS [ Thu Nov 02, 2017 5:05 pm ] |
| Post subject: | Re: 944 S2 fails to start :( |
Lack of tacho movement on an S2 when cranking, is a symptom of a fault with the combined speed/reference sensor on the flywheel. This will also prevent the engine from starting, as the S2's simple little electronic brain says "unless I see 200rpm, you're not getting a spark". It might be a faulty sensor, a dirty sensor or a fault with the wiring between the sensor and the ECU. |
|
| Author: | robmal [ Thu Nov 02, 2017 5:19 pm ] |
| Post subject: | Re: 944 S2 fails to start :( |
Thanks Glenn That was where my simple mind was getting to... will take a look at wiring and the sensor. Awkward to get to isnt it!!! Cheers |
|
| Author: | Endoman [ Thu Nov 02, 2017 7:04 pm ] |
| Post subject: | Re: 944 S2 fails to start :( |
My crank sensor was faulty but intermittant. Yes it's a fiddle to get at but not as bad as the 993 which was seized in. Not done the hall sensor yet but it's on the list. You can check the resistance at the plug ref Clarkes. |
|
| Author: | peanut [ Wed Nov 22, 2017 8:02 pm ] |
| Post subject: | Re: 944 S2 fails to start :( |
how did you get on Rob ? have you got it starting again yet ? Some closure on these non starting /running threads are always useful for others arriving here searching for a fix
|
|
| Page 1 of 1 | All times are UTC |
| Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/ |
|