What does a Cam Sensor do?
OK - so my beast would not start this morning! Turns over OK but would just not 'catch' and fire up. AA came over and guess what??? ..........Yup 'oh mate it does not have an ODB2 port so I can not diagnose this' (><) ( it this the automotive equivilent of "computer says No'?
However he thought that it maybe the cam sensor.... So its off to G Wagen in Caversham to get them to take a look and see what is what. Just fascinated as to what a cam sensor is/does.
Cheers in advance
Spider1V
Joe,
Are you sure that he said "Cam sensor" and not "Crank sensor"?
The crankshaft position sensor is a well know cause of MB engine non start. However, this normally occurs when the engine is hot. AA are certainly familiar with the roadside problem as they would get called to many.
Crank sensor or CPS is a straight forward repair in a workshop with a cold engine but a difficult one on the road side with a hot engine in the rain with family in transit. They normally last between 50-80k miles. I've done mine and carry a spare.
Cam position sensor is part of the engine management system, adjusts the timing reletive to cam position, you certainly need it
Did it work later on when it cooled down? A couple of things could possibly give you those symptoms...
Also the 99-01 Gs only had the MB 38-pin diagnostic connector under the bonnet. Most decent diagnostic scanners (read £1000+) come with an MB adapter, but you can keep one with you in the car for these times, they're fairly cheap:
http://www.google.co.uk/search?hl=en&tbm=shop&q=Mercedes+38+pin+OBD
Spider I had the same thing go on my E30 M3 engine and gear box out job over £1200 for a £50 sensor!!! Bets of luck!!
Does sound like a catch all diagnosis though. Could be something else. Didn't you say it was first thing. Icy cold? Lagging battery, slow turnover? It might start fine for MB when its warmed up in a workshop and no fault codes?
On my Saab, starter motor was weak and had failing starts (normally when hot too). Changed CPS (15mins) but needed a new starter to add some zest to the turn-over, then fine.
do those new fangled electronic engines have distributors if they do its where I'd look 1st.
No distributor. Each spark plug has a dedicated coil triggered by the ecu. Couldn't be simpler :)
as with most modern electronic engines, thanks
Sorry for the dealy with an update - ma wee beastie is back - lean mean V8 Machine, locked, loaded and ready for xmas!
It was the Crank Sensor - replaced and fitted for just under £90 at G Wagen Caversham. Anyone interested there is a members car down there being sold SWB - I know the member and took a look at his G - Very tidy and worth a look.
Sipider1V
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All many thanks for your replies:
@ Roly - hmmm I will check with the report that we sent to Caversham
@ M2x - Cheers that maybe something to ask santa for!
@ Lenny - 'thud' (sound of G Wagen owner fainting). I Hope not :(
@ Jdring - nope temp was a piffling 2.5 Degrees and engine cold. (had worked perfectly the evening before)
@ PRW - was is this 'dis-trib-u-tor' you speak of?
Should no later on today what is going on - just bracing myself for the worst now.... :(
Spider1V