Car wont start.

[STU3Y]

Was just hoping that this would prevent me having to wait for that.
Whats next for me to try

 

[shnazzle]

I'm just not 100% convinced it's fuel or sensor related. There are a few fuel pressure sensors and they're quite sensitive. If you've got no codes, I would think your fuelling is fine. The only thing that is not monitored is injectors, in which case you'd have a misfire...which would be logged anyway
Any and all sensors trigger an error code right away or eventually if outside voltage tolerances.

So...battery haha

 

[STU3Y]

Thats why I want to test. does anyone know what fuse to pull to do this?

 

[STU3Y]

1. lifted back seat can hear pump very easily when turning ignition.

2. removed pipe one and turned ignition. About 20ml of diesel comes out every time. nice and clean.
what next

so what does this rule out?

 

[MJ]

There's no fuel pressure sensors on a bkd engine. The injectors are the only thing that IS monitored.

What do you want to test? The battery?

 

[shnazzle]

There's no fuel pressure sensors on a bkd engine. The injectors are the only thing that IS monitored.

What do you want to test? The battery?

oh shite it's a BKD?
whoops?

EDIT: ah...yes there it is...in the OP doh!

 

[STU3Y]

Don't know how reliable it is, but at this moment car his fine and starting cos it hasn't been sat. When I put the multimeter on batt it reads 12.64, when Its started up it goes down to 10.61 and then up to the 14's whilst running.
From the videos I've seen it says below 9,6 would indicate batt is at fault but above batt is fine.

 

[STU3Y]

I'm a bit confused I'd like to make a list of possibilities and then rule each one out. My knowledge is very limited so would be grateful if anyone could compile it then we can tick them off. I'm quite happy to spend some money to fix it but don't want to waste money swapping bits for the sake of it.

 

[shnazzle]

"If a unit injector valve fails, the corresponding cylinder's injection is deactivated. In the event of a slight deviation from the control limit, the unit injector valve continues to be actuated. In each case, an entry is made in the fault memory."

"The ceramic glow plugs are actuated sequentially by the engine control unit....starting at an exterior temperature of less than 14°C"

 

[MJ]

You'll get fault codes but only if the component is electronically monitored.

If it's not missing or having the injectors closed down then it won't log a fault.

 

[shnazzle]

You'll get fault codes but only if the component is electronically monitored.

If it's not missing or having the injectors closed down then it won't log a fault.

So it seems the injectors do not have sensors, but the current for each injector is monitored by the ECU. And if there is a problem with the injector, it knows and throws an EML immediately.

Regardless...it runs fine once started...so it can't be that.

I'm dead curious now! What shall it be...

What's got me is that it does run once it DOES start. You'd swear it was a temperature sensor thing. Fuel temperature sensor? Maybe that's knacked and only putting a tiny bit of fuel in?

 

[STU3Y]

Can anyone compile a list of all possibilities.

 

[STU3Y]

Please!! That way each bit can be ruled out best as possible before I have to pay someone

 

[shnazzle]

Please!! That way each bit can be ruled out best as possible before I have to pay someone

Think you've pretty much got every option we could think of in this thread.

 

[STU3Y]

I know but im a bit lost to be honest, would really help if someone would list options, as not sure what ive ruled out yet if anything

 

[STU3Y]

1.GLOW PLUGS
Unlikely due to operating temp of 14 degrees - not checked

2. FUEL FILTER
Unlikely as no running issues - replaced now anyway

3. BATTERY AMPS
Unlikely as cranks well, not checked properly but on multimeter shows, 12.64 engine off, 10.61 when started, 14+ while running. Also battery condition lense still shows as green on battery itself, Is that considered ruled out?

4. FUEL PUMP - possible
Can be heard to prime, and delivers fuel into filter housing when ignition cycled. Ruled out?

5. CRANK SENSOR - possible
Possibly checked using torque app, revved at 211 first crank then 838 running, 117 second crank 838 running. (All of this is while the problem isn't present)
Need to check if revs rise when cranking next time engine fails to start.

6. CAM SHAFT SENSOR
Unlikely as would cause delay in start rather than failure to start. How do you check this?

7. INJECTORS
Unlikely as should throw up fault code - not checked

8. NON RETURN VALVE
???

9. FUEL TEMP SENSOR
???


Is there anything to add to this list or any points people can add/clarify that I might have got wrong to help narrow down the likely cause

 

[shnazzle]

1.GLOW PLUGS
Unlikely due to operating temp of 14 degrees - not checked

2. FUEL FILTER
Unlikely as no running issues - replaced now anyway

3. BATTERY AMPS
Unlikely as cranks well, not checked properly but on multimeter shows, 12.64 engine off, 10.61 when started, 14+ while running. Also battery condition lense still shows as green on battery itself, Is that considered ruled out?

4. FUEL PUMP - possible
Can be heard to prime, and delivers fuel into filter housing when ignition cycled. Ruled out?

5. CRANK SENSOR - possible
Possibly checked using torque app, revved at 211 first crank then 838 running, 117 second crank 838 running. (All of this is while the problem isn't present)
Need to check if revs rise when cranking next time engine fails to start.

6. CAM SHAFT SENSOR
Unlikely as would cause delay in start rather than failure to start. How do you check this?

7. INJECTORS
Unlikely as should throw up fault code - not checked

8. NON RETURN VALVE
???

9. FUEL TEMP SENSOR
???


Is there anything to add to this list or any points people can add/clarify that I might have got wrong to help narrow down the likely cause

1. Agreed
2. Replaced, so ruled out
3. Looks good, ruled out
4. Since you saw fuel coming out, and it's a PD (i.e. no common rail) then I'd be tempted to rule the pump out
5. Check when down, possible
6. Cam shaft sensor. Don't know what it's used for. No idea
7. I'm still convinced an error would be thrown, but MJ isn't. So still up in the air.
8. hmm...interesting. Possible. No clue how to test
9. I suppose if the car won't start one day, wait until its the opposite temperature and try again. Unless you want to do the old Russian Arctic trick of lighting a fire under the fuel tank hahah

 

[MJ]

An error would be stored - if there was a fault with them. Electrical malfunction and a misfire to be exact.

It could be the injector seals or the high pressure fuel pump in the engine bay. These are all just guesses by the way. I've even seen the starter motor cause problems on the bkd.

Have you got a video of the problem occurring?

 

[STU3Y]

No video sorry, I'll try get one if it does it again. Its very frustrating and confusing that it only happens when its sat for a few days, does keep making me suspect the battery as what else changes over a period of time other than the battery?

Added to list

10. STARTER MOTOR
How do I test?
11. INJECTOR SEALS
How do I test?
12. HIGH PRESSURE FUEL PUMP
How do I test?
13. COOLANT TEMP SENSOR
Mentioned by someone above. ?????

MJ what are your thoughts on the list so far

 

[shnazzle]

Hate to add another one to the list but here's a very likely candidate: fuel lift pump.

http://uk-mkivs.net/topic/91853-bkd-engine-gt-tdi-not-starting-me-and-the-garage-are-stuck/