Help corsa c 1.3cdti dying

[Afghanwarrior]

Hi all I have a 06 corsa 1.3cdti that has seen better days. I'm at my wits end with it, so before I take it to the garage I thought I'd ask you guys to help me.
It has no power
Fuel pressure is at about half
Boost is at 4psi
Smokes a little (black)
Rough idle
Hard to start when hot

It's not the
Fuel pump
Fuel filter
Fuel pressure regulator
Fuel pressure sensor
Water temp sensor
Or Turbo
I have checked or replaced these
What else could it be?
Only codes are p1612 p1613

[M32Guy]

Usual cause of those fault codes on the Corsa C is the plug at the back of clocks becomes loose. They don't really tie into your symptoms however but something to look at. I'd be taking a look at the EGR valve also. Try blanking it off to see if that improves things then you can replace it if that's the cause

[Afghanwarrior]

Thanks I was going to blank the egr anyway so I'll see if it's gunked up

[Classy6]

Answered your own question haven't you? Fuel pressure is half?

How have you tested the fuel pressure?

[Afghanwarrior]

I monitored it using my phone and a obd2 reader. I thing it might be an injector tho because I unplugged one and nothing happened (engine running) but why would this affect fuel pressure. Egr was fine aswell

[E-bmw]

Afghanwarrior said:

I monitored it using my phone and a obd2 reader. I thing it might be an injector tho because I unplugged one and nothing happened (engine running) but why would this affect fuel pressure. Egr was fine aswell

You say you tried this with "an injector" what about the others?

If it is running that poorly it might not be obvious that pulling one makes a difference.

As above though, fuel pressure radically affects how well the fuel is atomised & could well be you have answered your own question.

If nothing else it warrants more investigation.

[Mr2Mike]

E-bmw said:

As above though, fuel pressure radically affects how well the fuel is atomised & could well be you have answered your own question.

He's asking how could a bad injector cause low fuel pressure, not why low pressure causes poor running. It would have to be leaking off a huge amount of fuel to affect the rail pressure so badly, and that would have to be either going into the cylinder or back through the leak off pipe.

[Afghanwarrior]

E-bmw said:

You say you tried this with "an injector" what about the others?

If it is running that poorly it might not be obvious that pulling one makes a difference.

I have Un plugged the others and as expected it gets really rough.

[Afghanwarrior]

Mr2Mike said:

E-bmw said:

As above though, fuel pressure radically affects how well the fuel is atomised & could well be you have answered your own question.

He's asking how could a bad injector cause low fuel pressure, not why low pressure causes poor running. It would have to be leaking off a huge amount of fuel to affect the rail pressure so badly, and that would have to be either going into the cylinder or back through the leak off pipe.

"Going into the cylinder" meaning the injector is squirting loads of fuel? This might explain why foot to floor is slower than half throttle

[E-bmw]

Mr2Mike said:

E-bmw said:

As above though, fuel pressure radically affects how well the fuel is atomised & could well be you have answered your own question.

He's asking how could a bad injector cause low fuel pressure, not why low pressure causes poor running. It would have to be leaking off a huge amount of fuel to affect the rail pressure so badly, and that would have to be either going into the cylinder or back through the leak off pipe.

OK, I was answering his original post rather than the one immediately before which is why I didn't quote.

Of course you are right about injector leaking affecting fuel pressure.

[Classy6]

Afghanwarrior said:

I monitored it using my phone and a obd2 reader. I thing it might be an injector tho because I unplugged one and nothing happened (engine running) but why would this affect fuel pressure. Egr was fine aswell

How do you know what the fuel pressure is supposed to be? Assumed the data has specified values, however seems a bit advanced for a phone odb reader? What are your readings?

As others have said, if unplugging an injector makes no difference to engine running you have effectively isolated that cylinder to being at fault (theoretically). Have the leak off checked, as this could cause the drop in rail pressure if severe or if you have the time, swap the injectors over and see if it alters anything under the same test conditions with a different cylinder.

[Afghanwarrior]

Well I replaced the injector and it runs smooth and starts when hot but I still have no power. I have and egr code aswell p0400

[stevieturbo]

Some things are best left to die.

[crossy67]

Have you checked the EGR? Have you checked the data on your MAF? And have you checked for leaks on the intercooler and it's plumbing?

[Afghanwarrior]

Haven't checked maf or boost pipes. Not sure how to check the maf. Egr is blanked and actuator is free to move