fault code(17748 Camshaft/Crankshaft Position Sensors (B2) - Out of Sequence A)

Nov 2, 2004
9,335
0
South Wales
Yes i fixed mine. :D


If you've had your cambelt done recently, 99% of the time your timing is off. Dont worry, being off a tooth or two isnt the end of the world, theres quite a bit of clearance between valve and piston. Any more and you could be in trouble, but there if your gettin the code you know you havent bent any valves!

Ok first up...

Check the mark on the rocker cover vs. the mark on the crank pulley to metal cover when engine is at TDC.This can be done by cranking engine over to get the crank pulley marks to line up. Some people use the mark on the flywheel to the box casing, i'm not a fan of this as some flywheels done have the makr or have been marked incorrect. You can always use the screw driver in the head trick if your old school.

Crank Sprocket Marks...
DSCF1357.jpg


Cam Gear and Cover Marks....
DSCF1362.jpg


Flywheel And Box Casing Marks...
DSCF0640.jpg


Basically all these marks should line up if the car is in time.


If that all lines up then you have something else out.

Next if you've removed your cams for any reason at all then check the cam to cam timing. Again set to TDC. And check the windows on the drivers side sprocket of the cam to see if they lione up with the marks. See pics below.

Cam Gear Marks...
DSCF0646.jpg

DSCF0652.jpg


There should be 16 drive chain rollers between the marks and the notch on the exhaust camshaft is slightly offset inward toward the drive chain roller.

See here...

003.gif




If all this lines up then, like me, you have another problem, as the cam sensor (drivers side of head by the engine code) very rarely goes bad as with the crank sensor (near oil filter) then you have to look at either of your tensioners. It turns out my cam chain had stretched and the tensioner had died allowing basically slow in the chain causing the incorrect trigger between the crank and cam sensors.

Hope this helps, and if you need any help let me know.
 
Dec 3, 2007
2,475
0
cardiff
That is the biggest post I have ever seen LOL

I had this issue and it can just happen for no reason like me and phil found out in mine
 

cus

... Vag only!
Feb 8, 2004
1,713
0
Middlesbrough
www.nemm.co.uk
my god phil... thank you very much for that! when i get time over the weekend i'm going to check this all. the rocker cover has never been off, so should be a problem under there.

does anyone think it could be one of the two sensors mentioned?

cheers though! big help
 

cus

... Vag only!
Feb 8, 2004
1,713
0
Middlesbrough
www.nemm.co.uk
its been like this for months. sicne my timing was done at the my last service. have only done small stuff since... intercooler and n249 bypass.

car hasn't ever felt different, but i will check all this over the weekend and see what happens :) i'll keep you posted
 
Nov 2, 2004
9,335
0
South Wales
Like i say, those sensors hardly fail, and if they do, your car wont even crank over.

Happy to help as it pissed me off so much trying to figure out what to do.

Check the belt marks first.
 
Dec 3, 2007
2,475
0
cardiff
cranking the engine over means rotating everything

Is
As if the engine was started

Put a socket on the bottom pulley and rotate it clockwise this will in turn crank the engine around
 
Progressive Parts, performance parts and tuning specialists