Intermittent Long Crank (randomly once/twice a day)

[PearShaped]

Hi guys I hope you’re well. I’ve done a lot of reading up on the forum, but can’t seem to find a definitive answer on this, so wondering if anyone could help me diagnose an intermittent issue I’ve been experiencing please.



The van starts fine in the morning and 90% of the time during the day. However, at least once a day, after the van has been sitting for a while, it takes approximately 3-4 seconds of cranking before the engine starts. The cranking sound is normal, but it takes longer than usual for the engine to fire up. It feels like it’s not going to start, but then it suddenly does.



So far I’ve been told that it could include potential issues with the fuel injectors, sensors, or the fuel pump. I understand it might be challenging to diagnose since it's intermittent, but I’ve only recently purchased the van and it’s quite frustrating as I don’t want it to get any worse.



Has anyone experienced a similar issue? Normally it’s late afternoon before I go home from my last job, never happening in the morning.



Any advice would be greatly appreciated. It’s in for a cambelt change on the 28th and they’re also going to investigate for me but I’d like to understand myself prior to that if possible.



Thanks in advance

 

[James147]

Hi mate
I have had the same problem it’s been to main dealer they said earth strap and carried out a repair which did nothing, I then took it to an independent who couldn’t find a fault so I just live with it now which is annoying but it always eventually starts (90% of the time it’s perfect) if you do find a solution I can’t wait to hear it!

 

[Paynewright]

How old is the battery?

 

[DXX]

Hi mate
I have had the same problem it’s been to main dealer they said earth strap and carried out a repair which did nothing, I then took it to an independent who couldn’t find a fault so I just live with it now which is annoying but it always eventually starts (90% of the time it’s perfect) if you do find a solution I can’t wait to hear it!

Did they charge you for that?
All they has to do was put a jump lead from the battery negative to the chassis to prove it wasn’t the cause.

 

[JumpShip]

I had a similar issue last year , turned out to be a starter motor .
Didnt sound like it turned over any slower to me but eventually the cranking got longer and longer before it would eventually fire .
Took the plunge as i needed to sort it before a long trip to europe , been good ever since .

 

[James147]

Did they charge you for that?
All they has to do was put a jump lead from the battery negative to the chassis to prove it wasn’t the cause.

I think they had made enough money off me that day as it was in for service and mot pretty sure there was no charge for the fix that didn’t fix!

 

[James147]

I had a similar issue last year , turned out to be a starter motor .
Didnt sound like it turned over any slower to me but eventually the cranking got longer and longer before it would eventually fire .
Took the plunge as i needed to sort it before a long trip to europe , been good ever since .

That’s a good shout I don’t suppose there is a way of checking the starter until it packs in and with the stopstart it probably does more cycles in a year than an older engine does in 3/4/5 I will get a price on one , cheers

 

[Rob1978]

Hi guys I hope you’re well. I’ve done a lot of reading up on the forum, but can’t seem to find a definitive answer on this, so wondering if anyone could help me diagnose an intermittent issue I’ve been experiencing please.



The van starts fine in the morning and 90% of the time during the day. However, at least once a day, after the van has been sitting for a while, it takes approximately 3-4 seconds of cranking before the engine starts. The cranking sound is normal, but it takes longer than usual for the engine to fire up. It feels like it’s not going to start, but then it suddenly does.



So far I’ve been told that it could include potential issues with the fuel injectors, sensors, or the fuel pump. I understand it might be challenging to diagnose since it's intermittent, but I’ve only recently purchased the van and it’s quite frustrating as I don’t want it to get any worse.



Has anyone experienced a similar issue? Normally it’s late afternoon before I go home from my last job, never happening in the morning.



Any advice would be greatly appreciated. It’s in for a cambelt change on the 28th and they’re also going to investigate for me but I’d like to understand myself prior to that if possible.



Thanks in advance

I expericed similar symptoms when I first got my van, changed the battery which didn't help, then switchwd to premium fuel with some 300 plus miles runs and a service, its gone away. If your not used premium fuel might be worth a try ....at negligible cost

 

[PearShaped]

How old is the battery?

Not sure, but this is a pic of it

 

[PearShaped]

I expericed similar symptoms when I first got my van, changed the battery which didn't help, then switchwd to premium fuel with some 300 plus miles runs and a service, its gone away. If your not used premium fuel might be worth a try ....at negligible cost

Will certainly try this next time I fuel up, thanks

 

[PearShaped]

I had a similar issue last year , turned out to be a starter motor .
Didnt sound like it turned over any slower to me but eventually the cranking got longer and longer before it would eventually fire .
Took the plunge as i needed to sort it before a long trip to europe , been good ever since .

Hopefully the garage can check this when it’s in for the cambelt. Really frustrating as only had the van a couple of weeks

 

[mmi]

I don’t suppose there is a way of checking the starter until it packs in

Cranking speed (RPM) and starter current draw can be measured by using van's own sensors - thus simply via OBD socket - e.g. by using VCDS.

 

[mmi]

Any advice would be greatly appreciated. It’s in for a cambelt change on the 28th and they’re also going to investigate for me but I’d like to understand myself prior to that if possible.

Would be useful to know what engine - there are more than 20 different ones hardwarewise? What's the engine code - on configuration sticker under dash by steering column? What's the mileage? How old is the van - what model year?

 

[PearShaped]

Would be useful to know what engine - there are more than 20 different ones hardwarewise? What's the engine code - on configuration sticker under dash by steering column? What's the mileage? How old is the van - what model year?

Thanks for your help guys. I’m not very clued up on motors, so please excuse my lack of knowledge

 

[PearShaped]

Would be useful to know what engine - there are more than 20 different ones hardwarewise? What's the engine code - on configuration sticker under dash by steering column? What's the mileage? How old is the van - what model year?

Pic below of sticker, and 45,000 2019 plate. Thank you

 

[roadtripper]

You have an EFB battery, but at least it's a Varta and not the MOLL brand which seemed to give a lot of issues. If it's original it's now 5 or so years old so likely near the end of its usable life in a stop start van. I wouldn't change it just yet but if you get continued electrical weirdness keep it in mind and replace with a decent AGM type.

I would advise getting something that can read VAG specific codes, modern engines are almost impossible to diagnose from physical symptoms alone.

 

[Paynewright]

I have a CXGB engine in my 2018 plate van and changed the battery a few months ago - the original had a sticker on saying ‘Volkswagen Original Batterie’ also a Varta. Thats not to say yours isnt original - it still could be.

 

[PearShaped]

I have a CXGB engine in my 2018 plate van and changed the battery a few months ago - the original had a sticker on saying ‘Volkswagen Original Batterie’ also a Varta. Thats not to say yours isnt original - it still could be.

Would the battery effect it firing up? It turns over/cranks at normal speed and sound, not slow and sluggish as if the battery was failing

 

[mmi]

Pic below of sticker, and 45,000 2019 plate. Thank you

Thank you - perfect answer - including the sticker.
Engine is CXGB.
Besides that van has 70Ah battery (code J0V), 140A alternator (8GU), etc.

---

Anyways,

Would the battery effect it firing up? It turns over/cranks at normal speed and sound, not slow and sluggish as if the battery was failing

In principle it could affect as engine need to reach certain RPM before ECU even fires the injectors. However, the threshold RPM for this engine is quite low so would expect to be noticed well before as remarkably slow/sluggish cranking if battery was the suspect.

It feels like it’s not going to start, but then it suddenly does.

Very interesting observation - makes me think it could be camshaft timing issue. A possibility is the timing is at the edge where the ECU doesn't even fire the injectors but then the timing "slides" back into working zone.

Assuming when it starts it's immediately running on all cylinders - which makes me think it's a "centralised" no start. If the injectors were to blame would expect not to have all of them suddenly back alive.

The van starts fine in the morning and 90% of the time during the day.

Is the normal immediate start-up (< 1 sec), or does it include some cranking? Could you make a recording - a sound clip or video?

Well, as always a VCDS recording would be extremely helpful to eliminate quite a few basic factors:

1. cranking speed
2. timing offset
3. fuel pressure build-up
4. sufficient and correct airflow
5. injector firing

 

[PearShaped]

Thank you - perfect answer - including the sticker.
Engine is CXGB.
Besides that van has 70Ah battery (code J0V), 140A alternator (8GU), etc.

---

Anyways,

In principle it could affect as engine need to reach certain RPM before ECU even fires the injectors. However, the threshold RPM for this engine is quite low so would expect to be noticed well before as remarkably slow/sluggish cranking if battery was the suspect.


Very interesting observation - makes me think it could be camshaft timing issue. A possibility is the timing is at the edge where the ECU doesn't even fire the injectors but then the timing "slides" back into working zone.

Assuming when it starts it's immediately running on all cylinders - which makes me think it's a "centralised" no start. If the injectors were to blame would expect not to have all of them suddenly back alive.



Is the normal immediate start-up (< 1 sec), or does it include some cranking? Could you make a recording - a sound clip or video?

Well, as always a VCDS recording would be extremely helpful to eliminate quite a few basic factors:

1. cranking speed
2. timing offset
3. fuel pressure build-up
4. sufficient and correct airflow
5. injector firing

Thank you for the detailed response, very kind of you. Thanks also to everyone else for your replies, greatly appreciated. I will report back with videos as requested. I’m the meantime , Could I ask what you mean by “centralised” no start please?