2010 Golf Plus 1.6 TDI Cold Starting Problems

[Crasher]

It is an odd one as faults in the glow plug system are treated as emissions faults and so should come up using a generic scanner but often they don't so it would make sense to have it scanned with VAG specific equipment first to avoid replacing working parts.

 

[Adrian59]

Yes, I will do that. It seems like the glow plugs are working now anyway. It started first time this morning. May be it's something I did yesterday!
I'm considering buying a VCDS dongle, but I'm not sure if I will get my money's worth out of it once this problem is behind me.

 

[PatTDI]

Oh, ok. I used a generic scanner, but I guess I am clutching at straws really. I was wondering if the glow plug relay was failing on cold mornings.

I guess I’ll have to have a rethink.

I would take it to a garage but every one I have tried has said they can’t find a fault or have investigated and changed parts but there is no improvement, but I still have to pay the bill.

Any luck trouble shooting this issue ? I've the same problem with 1.6 tdi also. Same symptoms although I could travel any distance and leave the car 5 minutes and I would have the same issue. Dosnt miss a beat on the road just start up.

 

[Adrian59]

I am still working on it I'm afraid. I think the glow plug theory was probably a red herring although I haven't changed the glow plug relay yet, but as Crasher said, glow plug faults should show up in scan. The key thing with mine is that I only get the problem during the cold season in the first start of the day after standing overnight. Roughly speaking the temperature needs to be below 10degC otherwise it will cold start OK, which makes me think it's a temperature sensing element or something which is failing due to colder temperatures.
I have however found a possible workaround, which doesn't fix the problem but has improved things recently, and that is to cold start with a full throttle which makes the engine start with higher revs and then it is more likely to stabilise and be driveable on the first or second attempt. (I know this isn't a great thing to do with a cold engine, but I don't hold the high revs any longer than the initial surge)
Having gone through all the various diagnostics and parts changes wthout success, it is of course entirely possible that Crasher is correct that worn injectors are causing the problem, but economically it doesn't make much sense to change them, especially when I can't be sure they are the cause!

Did you get your car scanned for any faults?

 

[PatTDI]

I am still working on it I'm afraid. I think the glow plug theory was probably a red herring although I haven't changed the glow plug relay yet, but as Crasher said, glow plug faults should show up in scan. The key thing with mine is that I only get the problem during the cold season in the first start of the day after standing overnight. Roughly speaking the temperature needs to be below 10degC otherwise it will cold start OK, which makes me think it's a temperature sensing element or something which is failing due to colder temperatures.
I have however found a possible workaround, which doesn't fix the problem but has improved things recently, and that is to cold start with a full throttle which makes the engine start with higher revs and then it is more likely to stabilise and be driveable on the first or second attempt. (I know this isn't a great thing to do with a cold engine, but I don't hold the high revs any longer than the initial surge)
Having gone through all the various diagnostics and parts changes wthout success, it is of course entirely possible that Crasher is correct that worn injectors are causing the problem, but economically it doesn't make much sense to change them, especially when I can't be sure they are the cause!

Did you get your car scanned for any faults?

Well if its any help ive replaced the pump in the diesal tank with no luck filter with not luck and I've checked my glow plugs with a multimeter and they seem fine. No faults using any software. The problem started in October as it got colder but I got the car mapped in September. This had me thinking this was the issue. I had no issue with cold starts last year. Its been in the back of mind that it is injecter related but I really don't fancy paying out. I had planned on selling her but this puts a hold on that idea.

 

[Sullivankjs]

I have had a cold-starting problem with my 2010 Golf Plus 1.6TDI (105PS CAYC engine) for about 4 years. The problem only occurs in the winter months so I believe it is related to the ambient air temperature (or humidity). Usually I only get the problem on the first start of the day after the car is sitting outside overnight. It happens between about October and April/May. During the summer there is no problem.

When I try to start the car it initially fires up OK, but then over the next 5 - 10 seconds the idle becomes unstable and then the engine stops. It does not respond to the throttle during this period. I then have to repeat this usually 3 or 4 times, but up to 10!, before the idle remains stable and the car is driveable. Subsequent hot or cold starts are then OK until the next morning, and the car drives fine, although sometimes slightly hesitant in the first couple of miles.

I have had the car checked a few times by the local main dealer and a couple of independent VW specialists. The following have been checked and eliminated:

• Main dealer said cold starting problem was not caused by EA189 update (2 years after update)
• Fuel delivery system and fuel pressures checked by main dealer (all OK), fuel filter changed as it was "dirty" (no improvement)
• It was suggested that the cranking battery voltage was low. I changed the battery - No improvement
• Scans on VCDS show no faults, the engine temperaure (coolant) reading was correct for cold start
• Glow plugs have been changed - No improvement

Current mileage is 113,000. The problem started at about 75,000 miles/2017 and is getting slowly worse. EA189 emissions software update was applied by VW in 2017.

This issue is driving me (& my wife) mad! I am not sure what to try next. A couple of ideas I had were changing the engine air intake sensor, or maybe the immobiliser is playing up when cold??

Any suggestions would be gratefully received!

I would put a temp blank plate on the egr n see how that goes as EGR valves sfick n fail also theres a vw fix for the air mass fault = Replace connectors in plug to air mass...

 

[PatTDI]

I would put a temp blank plate on the egr n see how that goes as EGR valves sfick n fail also theres a vw fix for the air mass fault = Replace connectors in plug to air mass...

I'll give this a go in the next week or so. I got the dpf and cat gutted but I don't belive my EGR was blocked.

 

[Crasher]

I got the dpf and cat gutted but I don't belive my EGR was blocked.

Banned subject https://www.volkswagenforum.co.uk/threads/banned-subjects.11638 I am not going to rant about it as last time I was ragged...

 

[B100]

Have you confirmed that the pump in the tank is actually working in situ ? I've had two diagnostic tests on my Passat and they both failed to flag that the pump was not working. The symptoms are almost exactly what I've experienced with my car. You can listen for it when the ignition is first turned on before cranking the engine. If you can't actually hear the pump, then you need to confirm that the pump is receiving power which you can do by testing the voltage across the two thick wires at the plug leading to the tank.


2009 Passat 2L 103Kw TDI M6F

 

[PatTDI]

Have you confirmed that the pump in the tank is actually working in situ ? I've had two diagnostic tests on my Passat and they both failed to flag that the pump was not working. The symptoms are almost exactly what I've experienced with my car. You can listen for it when the ignition is first turned on before cranking the engine. If you can't actually hear the pump, then you need to confirm that the pump is receiving power which you can do by testing the voltage across the two thick wires at the plug leading to the tank.


2009 Passat 2L 103Kw TDI M6F

Yes I tried two second hand pumps just incase and they all primed with the half turn of the key and can be heard working. Nothing unusual in the tank either. I changed the filter as well when trying this just to be safe it wasn't drawing air.

 

[langelandsvik]

I have the exact same symtoms. Have any of you figured it out?

 

[PatTDI]

I have the exact same symtoms. Have any of you figured it out?

Sadly not. But the cars still running so there's that.

 

[langelandsvik]

Hi again. So I caved and turned my a3 in to a local shop. They did an egr delete, and the car has been working flawlessly for the last week. We have a really cold period now, but the car fires right up like it should.

 

[PatTDI]

Hi again. So I caved and turned my a3 in to a local shop. They did an egr delete, and the car has been working flawlessly for the last week. We have a really cold period now, but the car fires right up like it should.

Was holding off for a few days to be sure but I blocked mine yesterday after first cleaing the throttle body in case and its also stopped this issue. It was previously coded out when I got a remap to 140bhp but not blocked. The problem got to the point it happend every time I started the car hot or cold. Not promoting a egr delete but its a pain to remove the egr in my 1.6 tdi and I know where the problem is now.

 

[Crasher]

Pat, as I pointed out before, removing mandated emissions equipment is illegal and a banned subject on this forum https://www.volkswagenforum.co.uk/threads/banned-subjects.11638