FIXED: Jag X-type Crank no start

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picowight
OneWave
OneWave
Posts: 14
Joined: Sat Oct 26, 2019 6:45 pm

Re: Jag X-type Crank no start

Post by picowight »

Update on this, I was advised on another forum to scope an injector (now with current clamp!) and the common rain pressure.
I used the rulers to get the firing points of the other injectors (labelled in firing order) and it is quite clear that only injector 2 is actually passing fuel, this concurs with scoping inj 2 and crank signal, as I could see the rpm increase only when 2 fired.
An IMV + injectors unplugged pressure test showed that the pump is well short of it's maximum output but still has plenty pressure to flow fuel through the injectors.
The logical conclusion of this is that 3/4 of the recently replaced injectors are blocked, and a swarf check on fuel directly from the rail revealed that the pump is indeed emitting micro particles of metal. :(
So replacement pump, pipes, tank, sender, filter and injectors.

I think this Injector(s) + CR Pressure makes an excellent initial diagnostic test for a diesel, it confirms that injectors are getting firing signal, the pump has decent pressure, that the injectors are passing fuel, that the IMV is working, that there is no air in the rail and I expect (though not tried) that it would show if there was a high level of leak off on a specific injector.
Attachments
injector + FRP 2.JPG

Iver
TwoWaves
TwoWaves
Posts: 119
Joined: Mon May 27, 2019 2:55 pm

Re: Jag X-type Crank no start

Post by Iver »

Leak off is a test but never definitive.

I think you have blocked or broken injectors.

Swaptronics will help you prove this

picowight
OneWave
OneWave
Posts: 14
Joined: Sat Oct 26, 2019 6:45 pm

Re: Jag X-type Crank no start

Post by picowight »

Yes- they are a symptom. As above
The logical conclusion of this is that 3/4 of the recently replaced injectors are blocked, and a swarf check on fuel directly from the rail revealed that the pump is indeed emitting micro particles of metal.
Attachments
2019-11-27 15.18.37.jpg

picowight
OneWave
OneWave
Posts: 14
Joined: Sat Oct 26, 2019 6:45 pm

Re:FIXED Jag X-type Crank no start

Post by picowight »

Quick update, I replaced the entire fuel system.
Tank, pump, lines, filter, rail and injectors.
Still didn't start (only firing on 1 cylinder)! So I built a compression tester by butchering an old injector which gave a good result for the firing cylinder but low on the other 3 - this is a low one at 300psi
In Cyl Compression Cyl 4 wet.jpg
At the same time as taking these readings I swapped some injectors round and found that 3 out of 4 of my "tested" replacement injectors were not firing properly so I stripped and cleaned them and when replaced the engine starts and runs fine.

Really enjoyed learning about all the different things you can see from just a single waveform on the Pico.
When I get the chance I will take a known good cam/crank for the car and post it here so some one can upload it to the database as I don't have access ( I have the 2204A).

picowight
OneWave
OneWave
Posts: 14
Joined: Sat Oct 26, 2019 6:45 pm

Re: FIXED: Jag X-type Crank no start

Post by picowight »

Now it is running, as promised here is a Cam/Crank Correlation file for the X-type 06 Jag 2.0 Duratorq engine code FMBA known good.
I only have the 2204 so don't have waveform library access if a moderator/Pico employee would like to upload it, might help someone out.
Attachments
Jag x-type 2.0 d 06 cam crank running good.psdata
(167.13 KiB) Downloaded 24 times
Jag x-type 06 cam-crank 2.0 D Duratorq running good.jpg

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