Fuel rail/system pressure too low

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Paul-R
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Re: Fuel rail/system pressure too low

Post by Paul-R »

I don't know if there's another adaptor available but I found exactly the same problem back in 2020. The garage I borrowed the leak-off test kit from reckoned it should fit and (without saying it) that it was me that was fault.

viewtopic.php?p=647839#p647839

My injectors are Bosch and I guess yours are as well.
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piki
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Re: Fuel rail/system pressure too low

Post by piki »

what did u end up doing then?
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Paul-R
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Re: Fuel rail/system pressure too low

Post by Paul-R »

If you follow the link and read on you'll see I changed the injector without checking the leak-off. I'm not saying this would solve your problem, I was just agreeing that the leak-off testers appear to need another, different, adaptor.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
piki
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Re: Fuel rail/system pressure too low

Post by piki »

update , so i managed to do the eak off test , i removed the end with the o ring part, i took just the hose , and it was sitting good inside the return hole.
the bottels filled so fast , in like 20 sec it reach 80 ml on the right 2 injectors
added pics of the result.
i took the injectors out , remove the cap and the nozzle , cleaned it with utrasonic cleaner , put them all in , and did the test again , it gives pretty much the same results, (right side injectors fills faster then the left.
but in much slower pace.
dono what else could be blocked in the injector?
can i put the injector as 1 piece in the ultrasonic cleaner?
will see if the light come on again...
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piki
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Re: Fuel rail/system pressure too low

Post by piki »

the light turned on again after 10 minutes
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Paul-R
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Re: Fuel rail/system pressure too low

Post by Paul-R »

Run a Diagbox read again, see if the error(s) are the same. While the engine is running see what the figures for the fuel flow/correction for each injector is.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
piki
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Re: Fuel rail/system pressure too low

Post by piki »

the code is the same , i will run the diagbox and will upload the results, i have seen in ebay genuine injectors , so thought about swapping the right 2 injectors.
i was thinking about taking the injectors out again , and try run it with pulses with a carb spray attached(youtube)...
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Re: Fuel rail/system pressure too low

Post by Paul-R »

Assuming that the cylinders are showing from 1 to 4 try swapping around the injectors for 1 & 2 for 3 & 4 to see if the fuel bypass flows change with them. Also see if a different error code is registered.

t's a bit of a faff and you'll have to code in each injector but it's virtually zero money cost, just time.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
piki
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Re: Fuel rail/system pressure too low

Post by piki »

whats code in?
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Paul-R
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Re: Fuel rail/system pressure too low

Post by Paul-R »

Each injector has a specific code printed (somewhere) on it. This needs to inputted to the engine ECU so that it can provide the correct metering for injecting the fuel. You will need something like Diagbox to do this.

It might be worth checking to see whether the correct codes are coded in already as if the wrong code is there it will cause poor performance.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
piki
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Re: Fuel rail/system pressure too low

Post by piki »

Can a clogged injector be clean in other then the way that i already did, (take out the nozzle)?
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Paul-R
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Re: Fuel rail/system pressure too low

Post by Paul-R »

I don't know, sorry.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
piki
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Re: Fuel rail/system pressure too low

Post by piki »

Diagbox today
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piki
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Re: Fuel rail/system pressure too low

Post by piki »

have no idea how to read it, i thought it should be like a graph that moving up and down.
what are the meaning of the minus 03 mg/impulse?
piki
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Re: Fuel rail/system pressure too low

Post by piki »

while the vehicle is standing , even if im pushing the pedal , the fuel pressure value , and the fuel pressure are the same at all rpm(did it with Diagbox open) , but once i start driving , after few minuts the light will turn on.