1kd p0093.. need help

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Hello everyone, I'm trying to diagnose a p0093 fuel leak, large leak detected error that comes on a hilux.. its an intermittent problem... so far I've got its injectors tested, pump, common rail.. all is good.. intank strainer and diesel filter have been replaced and still get the error . i have a few shots of the freeze frame if you guys can look at it and point to anything 

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it's not building pressure under load or dropping off - I would look at the SCV, whats a common issue, especially if it's the short body or has had the recall with the spacer and short SCV

don't mess with cheap or recon SCV go for the Denso item

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in such cases scv current draw is high or erratic along with erratic engine running, in my case scv current draw is pretty much consistent and engine running is smooth and powerful

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Look at the fuel pressure 1000 Kpag - 145 psi and your 5-6000 Kpag low

it's in your freeze data, it's dropping under load, so idle and general load will be untouched

or the pressure reg is dumping fuel/pressure above a certain level

 

Contaminated fuel is a possibility maybe algae growth, but you would see that in the old filter if you cut it open

 

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i think its because as soon as cel turns on the engine shuts off.. fuel is not contaminated, we removed the tank and confirmed 

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so.. did some more tests today and confirmed that the common rail relief valve is not dumping the pressure excessively, it only dumps when commanded by the ECU and none otherwise.  removed the SCV to inspect, found nothing.........

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what is there to inspect on SCV its a sealed unit unless you have the tools there is nothing you can do to prove it's not worn or has an intermittent issue

It turning off as it is starved for fuel - a code is a diagnostic aid, not a cure or the issue

Here is the OEM definition of the code.............

This DTC indicates fuel leaks that exist in high pressure areas in the common rail system. The ECM constantly monitors the internal fuel pressure of the common rail after the engine is started. The ECM sets this DTC if the drop in the internal fuel pressure is large when injecting the fuel.
In the common rail system, high-pressure fuel is always supplied to the high-pressure areas including the supply pump, common rail, injectors and piping. The ECM adjusts the suction control valve opening angle to obtain the target internal fuel pressure.
If this DTC is set, the ECM enters fail-safe mode. The fail-safe mode suspends both fuel injection and supply pump operation and then stops the engine. Before stopping the engine, the ECM permits the vehicle to be driven for 1 minute. The fail-safe mode continues until the ignition switch is turned OFF.

 

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could it be the common rail pressure sensor itself?

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Replaced the common rail assembly, the common rail pressure sensor was the suspect, its been almost 300 kms.. problem hasn't re-occurred so far.

will update further 🙂 

[flash22]

on the end of the rail is a mechanical fuel pressure relief that could have been letting past

eg.

095420-0272

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Yeah, it was tested thoroughly, its an electro mechanical relief valve.

 

anyways, just here for an update: 

the vehicle has now run almost 700 kms after the common rail replacement - all good