none start TD5 after rebuild

Hi
After a huge rebuild of the engine TD5 disco 2 im now in the position that the engine won't start. When it turns the rev counter doesn't even move so im thinking cps may be faulty but no idea why this would have happened.
On the ecu which two leads go to the sensor. And if i check with ohm meter what reading am i looking for for a good or faulty sensor.
Ive fitted new head with all old injectors etc., new big end , cylinder hone , new oil water and steering pump. When I crank I get white smoke out the back smells a lot like diesel and engine almost seems to be ready to start but won't. The lack of any movement on rev counter is concerning me. My nano com have decided to show error No firmware found for some reason as as using a mac cant reboot it so cant check with that
Any hints or advice on this non starter and the cps i think is the issue would be very welcome.
Thanks
John

Usually on CPS fault the ECU doesnt open the injectors so you would not smell anything at the exhaust, you can't rule it out with resistance check, check voltage on the battery while cranking cos if it drops below 10.5V it will hardly start, if it's manual try to bump start it...if still no joy i'd say to better double check the timing to be well set.

Pins 13 and 36 with the screen going to pin 16. If the screen is not connected there could be enough interference to degrade the signal which would also prevent a start.
I would start with a continuity check across pins 13 and 36 to check the wiring integrity before you assume a dead sensor. There is no steady current to read as it generates a magnetically induced pulse that is only there when the flywheel is rotating.
From very recent (yesterday) experience, it is quite possible to break a connection at the socket when refitting. Though in my case it was a Defender 90 and it was refitting the air intake that put strain on the cable.
The wiring in the original loom could well be starting to deteriorate. On my son's Defender at the sensor it had broken down to the point where it could not be used, and when I took the red plug apart at the ECU I found the the +ve and -ve wires both had breaks in the insulation just before the plug.

thanks very much I will check this. And on cranking should the rev counter move at all ? Going to check this Sunday

sierrafery said:

Usually on CPS fault the ECU doesnt open the injectors so you would not smell anything at the exhaust, you can't rule it out with resistance check, check voltage on the battery while cranking cos if it drops below 10.5V it will hardly start, if it's manual try to bump start it...if still no joy i'd say to better double check the timing to be well set.

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Hi Thanks for that
With the timing i had the locking pin in the bell housing and the locking pin in the cam shaft. I had taken everything to pieces before but assume that with both pins in and the coloured links with the cam pulley mark all lined up im assuming that the timing would be set correct. I will check everything lines up. Any ideas on that would be great. Going to check all wiring to cps as think with no movement at all at rev counter something isn't right
Thanks

The rev counter doesnt move at all untill 230rpm that's how it's set from factory

I would loosen the bolts on the cam pulley and retard the crank a tiny bit. It can be really hard to start if it’s not in the sweet spot. A mm here or there can make a lot of difference.

Did you run the purge process?

Alpinejim said:

I would loosen the bolts on the cam pulley and retard the crank a tiny bit. It can be really hard to start if it’s not in the sweet spot. A mm here or there can make a lot of difference.

Did you run the purge process?

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Hi

So yes I did purge. as far as I know. Whats the exact sequence ?
Also ive tried changing the timing as you said with varied results. Got a lot more life when I adjusted it fully the other way it was. Smoke out the back and a hot exhaust but still won't run. The starer motor seems to be starting to not like all this trying!!!!
Need to get my nano com back up and running as its some how deleted all the firmware and with an apple mac i can not reinstall it.
Almost ready to give up on the beast now. Any ideas would be great

To purge the fuel lines you turn ignition on, don’t try to start.
Then pump the throttle 5 times quickly until CEL starts flashing.
Then go and make a cup of tea. It will take a few minutes to complete the process.
However, I found that having the timing set correctly (for my engine it’s just off centre of the pulley slot) makes a huge difference when starting. You can purge all day but if the timing isn’t close enough you’ll be wasting your time.
Try lining up the slot near the centre, purge once and try to start. Then adjust the slot, you shouldn’t need further purges, it should then just be about finding the correct timing.

Hi
Yep never did that properly so will try that. Without that could it really stop it starting ? And is the timing that fragile that a mm off it won’t start ?
Driving me mad now. Engine seems to be almost starting with smoke out the back and exhaust heating up but won’t run.
Thanks
John

When I checked my CPS lead I didn't get continuity from the plug to the pins on the red ECU plug. I bought a made up lead from someone whose website I can't remember. Fine after that.

The gist is in the first two posts though ..and this

Engine seems to be almost starting with smoke out the back and exhaust heating up but won’t run.

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, CPS signal failure doesnt let the ECU to open the injectors

Winter Rover said:

Hi
Without that could it really stop it starting ? And is the timing that fragile that a mm off it won’t start ?
John

Click to expand...

I’d say yes. I’ve spent ages trying to start, running purge after purge thinking that there was still air in there but when I hit the sweet spot on the timing, it fires up immediately.

I realised then that one purge should probably do the job - unless you have other problems, and it’s just then about finding that sweet spot.