2015 Golf TDI long crank first start of the day

[Spakainz]

Hello I'm still struggling with a long crank after night (ea288) . I've noticed that the intake air temperature sensor works strangely. I attached a photo with graph. In the graph, when the engine is idling, the sensor measures temperature correctly. But when the engine is turned off and the ignition is turned on again, the temperature rises up to 150 degrees celsius,when engine starts again the temperature drops to -5 and then returns to normal +8 degrees celsius. Maybe you can check if this is the case with you. The outdoor temperature was +5.

Screenshot 2024 11 18 141514 — Postimages

postimg.cc

 

[jrn_stu]

I'll be checking that and let you know.

Did you have longer crank when you made that graph?

Have you tried measuring intake air temp behavior when car was warm?

Besides that, I'm not sure if I have written that previously, but I had weird electricity behaviors that might be related to longer cranking. Although, it could be that it is the result of the longer cranking and not the the reason why I have longer cranks.
In last 3-4 years I had problem with:

• MMI soldering being burnt and more on that problem on a link (lost sound on 3 speakers in the car)
• Auxiliary Heater connection isolation was melting and I had burning smell going through air vents - link (resolved with turning off the auxiliary heater in MMI but I'm now freezing for the first 5 mins on cold weather )
• my left xenon bulb and ballast got burnt and had to change it (now I have weird behavior where my xenon bulb is on when I have ignition on, but sometimes it turns off when I start the car. Its in a process of resolving with my electrician)

 

[Spakainz]

I'll be checking that and let you know.

Did you have longer crank when you made that graph?

Have you tried measuring intake air temp behavior when car was warm?

Besides that, I'm not sure if I have written that previously, but I had weird electricity behaviors that might be related to longer cranking. Although, it could be that it is the result of the longer cranking and not the the reason why I have longer cranks.
In last 3-4 years I had problem with:

• MMI soldering being burnt and more on that problem on a link (lost sound on 3 speakers in the car)
• Auxiliary Heater connection isolation was melting and I had burning smell going through air vents - link (resolved with turning off the auxiliary heater in MMI but I'm now freezing for the first 5 mins on cold weather )
• my left xenon bulb and ballast got burnt and had to change it (now I have weird behavior where my xenon bulb is on when I have ignition on, but sometimes it turns off when I start the car. Its in a process of resolving with my electrician)

The same situation is with intake temperature sensor no matter engine is cold or warm. Yes, I have couple times with long crank, when did these logs. But I suspect, that the culprit of long crank may be camshaft position sensor. Please let me know what is your intake air sensor behaviour.

 

[RIP TDI]

• Auxiliary Heater connection isolation was melting and I had burning smell going through air vents - link (resolved with turning off the auxiliary heater in MMI but I'm now freezing for the first 5 mins on cold weather )

There is a redesigned heating element for the VW Mk7, p/n 5Q0963235E, that addresses the melting issue. I don't know how or if this translates to A3 applications.

 

[jrn_stu]

Hello I'm still struggling with a long crank after night (ea288) . I've noticed that the intake air temperature sensor works strangely. I attached a photo with graph. In the graph, when the engine is idling, the sensor measures temperature correctly. But when the engine is turned off and the ignition is turned on again, the temperature rises up to 150 degrees celsius,when engine starts again the temperature drops to -5 and then returns to normal +8 degrees celsius. Maybe you can check if this is the case with you. The outdoor temperature was +5.

Screenshot 2024 11 18 141514 — Postimages

postimg.cc

The first cold start had normal air temp values. pic1 link

All starts after the first one had the same behavior as yours. See the pic2 on a link.

I would not say that is the reason, but who knows.

Also, I'm not sure if I had written it before, but when the glow plugs are visually on for a longer time (>2 sec on a dash) I always have normal start. Only when glow-plugs light on a dash is on for a <1 sec I might experience longer cracking. Maybe if the glow plug on time could be somehow set to be always above 2 sec or something like that.
It could also be that, when glow plugs are on <1 sec, that the heat provided by glow plugs is not enough to burn the carbon so sometimes the longer cranking is achieved. Again, all is just a speculation.

 

[Spakainz]

Hello. I think I found reason of long crack. I've cleaned camshaft position sensors contacts and reconnected connector. And now engine starts like new. Try to clean contacts.

 

[jrn_stu]

Is it cam or crank position sensor?

First thing I did was the cam position sensor change but the long cranks remained.

People previously reported that changing the crank position sensor resolved long cranking problem.

Let us know if your change resolved problem fully for you.

 

[Spakainz]

I cleaned camshaft. Please read vw self study previous ea189 about camshaft and crankshaft sensors. When is camshaft sensor failure, then is longer start of engine, with faulty crankshaft sensor is not long start. I think same is with ea288.

 

[nickdvm]

I replaced my VVT valve and cover this past Monday and slow start problem solved. Our 2015 GSW has had intermittent slow first starts since the time we bought it from VW. It really became evident on EVERY first start in the AM this summer while we were in Montana. We live on the Gulf Coast. I just chalked it up to thin air. Problem mostly went away, well returned to it's normal randomness, after our trip. Over the past month it became every start after sitting overnight. I was positive this was going to destroy the battery and it may have significantly reduced its life span.

But, here is my big question, even though my problem appears to be solved. I noticed when cranking there is no load reduction mechanism in a load reduction relay. AC fans run, radio plays, headlights are on, dash and interior lights are on. ***?! A work mate has a '24 GTI. Same thing. We've both scoured the schematics and based on simple observation a 2015 DIESEL and a '24 GTI have NO load reduction mechanism/relay. Is this just another VAG cheap out so they can sell more batteries? What gives? This is probably worthy of a separate thread but there is no discussion that would solve a problem unless someone has figured out how to install a LRR on a late VAG car. Wish I never got rid of my ALH wagon for this problem child.

 

[ticaf]

I don't think load reduction is needed here. Sure, it might help if the battery is really weak, but then that battery needs replacing anyway.

 

[ZippyNH]

One less thing to fail....
Simply a cost benefit analysis....many items use far less power than before... battery is decently sized, radios use less power than they once did, as do radios...and the car has a HUGE alternator so even on short trips, the car should have a full battery when parked...very different than a few years ago when a 50 amp alternator was common or back further when generators were the norm.
Apparently they chose right cause 99% of people never have an issue or reason to think about it.

 

[nickdvm]

Good feedback, thanks. I was just thinking 'OK, AC fans(I'm in Texas, they are always on max!), fancier stereo, are a big draw'. Maybe they aren't such. I know all the interior lighting, DRL's, etc are much lower loads being LED's. I also agree with the cost cutting issue, one less part and probably a simplified wiring harness. I think manufacturers, also, would rather sell you a new battery that needs( well, some) programming. Now days, I think they cut corners wherever they can. Like putting ****ty wire harness protection on the harness that runs adjacent to the intercooler that chaffed and grounded out in 2 places causing the engine to die. That was fun to chase down!

As far as the one less part to fail, I cant disagree with that. But, I'm in my '50's, a gearhead, and I've lost count of the cars of all types I've owned between myself and my wife(also gearhead). I've never had a LRR fail. Plenty others though! I've probably jinxed myself and all my "old" cars are going to start dumping their LRR's!

Thanks for the replies!