2013 seat 2.0 CR extended crank from cold.

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Frs2180
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Joined: Wed Apr 25, 2018 6:36 pm

2013 seat 2.0 CR extended crank from cold.

Post by Frs2180 » Thu Aug 08, 2019 7:35 pm

Got a seat diesel in engine code CUPA with an extended crank time. Measuring rail pressure on scope from rail sensor the HP seems to be building pressure to 1.2 ish volts where it peaks and drops to 1v and back to 1.2v with every revolution of the hp pump until it builds to over 1.3V- 1.4V and the engine strikes up. This happens again if you turn off and restart after a few seconds. But if you drive the vehicle for a every short distance it cranks and starts fine. One thing I've noticed is the priming pressure when it's got a long crank tends to build slowly. When it cranks and starts ok the priming pressure peaks at 75 psi the second you hold the key in crank. Duty on drv and inlet metering valve doesn't seem to change when fault is occurring. It's as if the low pressure pump is priming to slowly??

Technician
TwoWaves
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Re: 2013 seat 2.0 CR extended crank from cold.

Post by Technician » Thu Aug 08, 2019 10:02 pm

Have you used the scope to check voltage against pressure?

landroverman1958
OneWave
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Re: 2013 seat 2.0 CR extended crank from cold.

Post by landroverman1958 » Fri Aug 09, 2019 5:52 am

Hi just check the current drawn by the in tank fuel pump,through the access point under the rear seat,o/s usually,8 to 10 amps,using an amp clamp,watch initial turn on and will probably just show a prime pulse.

Frs2180
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Re: 2013 seat 2.0 CR extended crank from cold.

Post by Frs2180 » Fri Aug 09, 2019 11:45 am

current ramping on pump seem to peak at around 8 amps. run again this morning and priming pressure built up to 75psi the second the key was in the crank position but I still got an extended crank.

landroverman1958
OneWave
OneWave
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Joined: Thu Dec 04, 2014 7:53 pm

Re: 2013 seat 2.0 CR extended crank from cold.

Post by landroverman1958 » Fri Aug 09, 2019 4:44 pm

Good evening,sounds like you have an high pressure leak possibly an a injector leaking back,why dont you carry out a back leakage check,and or koeo crank with the injectors disconnected electrically,and observe rail pressure rise?has this engine got an electrical connector for a pressure regulator?pressure sensor one end regu
lator the other end?
DO NOT disconnect the injectors with the engine RUNNING,

Frs2180
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Posts: 7
Joined: Wed Apr 25, 2018 6:36 pm

Re: 2013 seat 2.0 CR extended crank from cold.

Post by Frs2180 » Fri Aug 09, 2019 5:58 pm

Yes it has a DRV on the rail. Customer unfortunately has taken vehicle away as it's needed. I suspect a leak some where as scoping the pressure sensor the rise time has some small drops in as it builds pressure doesn't rise and hold but seems to drop slightly. Thanks for the info. Will see if the customer returns

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