Po335 fault is kicking my butt

[Davewatto]

Hi I've got a 2007 vsk d40 it has a yd25 which has been freshly built put it in took a bit to start but got there,
On about the 5th start long cranking and po335 and po403 code appeared
First up I've swapped out crank and cam sensors. Looked at wires for damage, pulled down front of motor to check timimg reset it for good measure .
I'm now looking at wires and ecu
I've hooked up my scanner and put it in live feed I've noticed at idle both cks tdc readings were around 780 rpm speed then for a about 4 seconds the 1st one jumped to 4300rpm the 2nd dropped to 0rpm
The engine didn't alter rpm and up popped the fault codes and back to square one any ideas I'm not sure how to test ecu or how to find point of interference
Any help would be appreciated thanks Dave

 

[Old.Tony]

I'd have a look for magnetic interference. Had a couple of instances years ago where metallic particles were attaching themselves to the magnets of the crank sensor and causing interference.

Also ensure that there's a very good electrical connetion between the sensor and the earth body.

 

[Davewatto]

Thanks Tony it's all clean
I've done a few more things now like striped down the loom and checked all wires individually all good there
New sensors fitted
Had it on a scope looks good while running but on start up no signal
I have had 2 aut0 elecs looking at the problem 1 could not work it the other said to start changing parts like ecu relays starter motor have the ecu not fitted yet but will update as we go thanks again

 

[Davewatto]

Solved it was a damaged ecm from a faulty alternator