Thanks for that. Do you hav a link where I can find how to measure the resistance on injector 3. Have been searching round but cannot find the exact procedure.

I don't have link but it is very simple. You will notice that injector 3 is different. It is taller and has a wire coming out of it. If you follow the wire you will find a connector about 40cm away. Unplug it and check the pins of the connector for corrosion. Using a multimeter on resistance (Ohms), put the probes on the 2 pins of the connector that leads to the injector and read off the value. Move the wire about and check the reading doesn't change.

I don't have link but it is very simple. You will notice that injector 3 is different. It is taller and has a wire coming out of it. If you follow the wire you will find a connector about 40cm away. Unplug it and check the pins of the connector for corrosion. Using a multimeter on resistance (Ohms), put the probes on the 2 pins of the connector that leads to the injector and read off the value. Move the wire about and check the reading doesn't change.

Thanks for that. I am new to this and all assistanc is much appreciated.

I don't have link but it is very simple. You will notice that injector 3 is different. It is taller and has a wire coming out of it. If you follow the wire you will find a connector about 40cm away. Unplug it and check the pins of the connector for corrosion. Using a multimeter on resistance (Ohms), put the probes on the 2 pins of the connector that leads to the injector and read off the value. Move the wire about and check the reading doesn't change.

rwbaldwin, thanks for the explicit procedure.

We measured the resistance over the two pins with the ignition both on and off- the readings in both instance were 0Ohms

As a test we cranked the engine with the lift sensor disconnected.

The engine did start as before (long crank).

We were intending to disconnect the No 3 injector union to verify the fuel flow as suggestd but after 13 years in place (not having been removed before) it seems to be welded!!! -

Really afraid to place too much purchase as it may break the injector itself

Does this mean our lift sensor is knackered?

rwbaldwin, thanks for the explicit procedure.

We measured the resistance over the two pins with the ignition both on and off- the readings in both instance were 0Ohms

As a test we cranked the engine with the lift sensor disconnected.

The engine did start as before (long crank).

We were intending to disconnect the No 3 injector union to verify the fuel flow as suggestd but after 13 years in place (not having been removed before) it seems to be welded!!! -

Really afraid to place too much purchase as it may break the injector itself

Does this mean our lift sensor is knackered?

I wasn't suggesting that you remove the injector - just loosen the union nut that holds the fuel pipe onto the injector. As you crank fuel should leak out between the union nut and the injector.

If you had the multimeter probes connected to the wires leading to injector 3 and you got zero ohms then the needle lift sensor and therefore the injector is faulty. Makes sure the scale of your multimeter allows you to read 80-120.

I wasn't suggesting that you remove the injector - just loosen the union nut that holds the fuel pipe onto the injector. As you crank fuel should leak out between the union nut and the injector.

If you had the multimeter probes connected to the wires leading to injector 3 and you got zero ohms then the needle lift sensor and therefore the injector is faulty. Makes sure the scale of your multimeter allows you to read 80-120.

Hi

yes we did try to unsuccessfully slacken the union of the injecotr but we did manage to disconect the fuel pipe coming from the inection pump to injector three and got fuel there

Is there any further tests way to confirm (with VCDS or othrwise) that the injector 3 is definately faulty. I have access to the lite registered version?

We are confident that the ohms test was accurate using the approprite scale

As a matter of interest - can you advise a link wherby we can purchace a single No 3 injector?

Thanks for all the help and advice

Do you have any thoughts on the fact that we cranked the engine with the lift sensor disconnected made no difference to the long crank start.

Edited 29 June, 201313 yr by bluehair

With a faulty/disconnected needle lift sensor the timing will be out (retarded) so you will have trouble starting (as you already know). You may get a code with VCDS (17654 or 17655) but not always.

The needle lift sensor is just a coil. The definitive test is to measure the resistance. One thing it is worth doing is to bend the cable to the injector at 1cm steps along its length with the meter still connected. If you suddenly get a resistance reading, then you may be able to repair the wire.

Thanks rwbaldwin.

 I am going to see if I can pick up a second hand injector 3.

I will let you know how it goes.

Well, what a sga.

I obtained a second hand injector. Checked it and it had no resitance. To cut a long story short our meter was faulty. It turns out our injector 3 is ok. 102 Ohms. Bloody hell....

I also replaced the CTS. After a day the warning light no longer comes on.Hoping this will has solved not starting when hot.

 

However we still have long crank time.

We have removed the union nuts for injector 3,4 and 2. All are being supplied with fuel. Couldnt get 1 off.

Whilst injector 3 was disconnected it started on the other cylinders. The same was for 4.

We could not get it to start with injector 2 disconeted. Not sure what this tells me to be honest.

Have flushed it with injector cleaner.

 

Going to look at the crank speed with VCDS. Some of the suggestions were starter motor.

Its becoming a challenge now :sun:

I have now measured the crank speed using VCDS.

It sits above 250 rpm.As you can see the engine does start. The engine wasnt fully warmed but not cold. The measured temperature was 63c.

 

I am going to try it again with the car fully warmed. It does tend to be more difficult to start when been on a longer journey.

 

It takes almost 6 seconds to start.

 

The smell of unburnt fuel is overpowering.

 

What else can I look at with VCDS to help me.

 

Cranking looks fine then. You really need to get the engine up to normal operating temperature(88C ish) & then look at the temp the ECU is getting from the CTS. 

Have also looked at the Injection Quatities. There is a massive spike before it starts is this normal.

 

After a bit of research The IQ value should be anywhere between 1 and 3. I have 10.1. The higher this value the lower the amount of fuel. I should therefore have very little fuel being injected.

I am not sure if I trust this ready. Some sort of sensor must be broken.

Cranking looks fine then. You really need to get the engine up to normal operating temperature(88C ish) & then look at the temp the ECU is getting from the CTS. 

 

Have checked the crank speed with the engine warm.Crank speed is better.So I can rule out the starter motor.

Long time since I have updated on my starting problem.

I had to put my car off the road as it was becoming unrealiable.

I was determined to get to the bottom of my issue. My car has sat on my drive since last October.

I am now the proud owner of a VW Passat 2004 1.9 TDI 130BHP.

 

However back to the Octy.

I had tried basically everything. I managed to get a fuel pump off ebay so I thought I would try it.

With some help I have swaped out the fuel pump.

 

To my amazement the car started first time. The bad smell of unburnt fuel gone.

Starts every time / first time.

 

Now I have to fix all the other problems. This car is more of a hobby. No pressure as its no longer our family car.

 

The final outcome may help someone else with similar symptoms.

 

Cheers

Paul

Edited 14 September, 201411 yr by bluehair

Have you checked the potential difference on the earth connection's. Especially under/ around the battery?

Oops sorry forget last message i posted that before reading entire thread.

Hi Paul

Did you get any further with this?

Does it still start well with the new pump even when hot?

Mine has similar long crank issue when hot. (2000 1.9tdi Octy1)

It starts ok when cold, just takes a long time to start when hot

as if it is having to build up the pressure again.

I suspect a cracked injector or something, but I thought maybe a valve in the pump.

It runs fine and has good mpg. No fuel smell, just smokes a bit when overtaking.

Looking for a diesel test place in NW london to check the injectors...

Any recommendations? anyone?

Snaler. .mine is the same as yours. Takes a while when hot . Although starts immediately when cold with 158000 on the clock. I just put it down to the fact it does not have a lift pump in the fuel tank.

In my experience the 2 most common causes of hot starting problems are the coolant temp sensor & the cam position sensor.

Snaler. .mine is the same as yours. Takes a while when hot . Although starts immediately when cold with 158000 on the clock. I just put it down to the fact it does not have a lift pump in the fuel tank.

Could be a poor battery or a lazy starter. When hot fuel isn't injected until the engine is doing 250rpm but when cold fuel injection starts straight away. Try disconnecting the coolant temp sensor and the try when hot.

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