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!

 

[radiator]

struggling continue.......
I found a video on YT where a bloke shows that cleaning the crankshaft sensor resolved long crank issue. So I had it cleaned but the next day long crank was even longer than usual. The problem occurs every morning since than and what is even worse then precleaning. Before the sensor cleaning every second engine run no crank and now no vcds nor on the dashboard errors son no idea what to do now.

 

[Catarinoforlife]

I just wanted to share an update. I haven’t had a long crank in over a year. There has been little things that made it better and less frequent, like a new battery(AGM) and the new crankshaft sensor. I never tried cleaning the cam vt valve or swapping it over.


When I did my timing belt, I also changed the alternator, as its voltage output wasn’t ever going above 13.2V. Now I will see it go above 14.0V every once in awhile, but mostly hovers at 13.8V. During the Timing Belt change, I also took care to make sure the high pressure fuel pump was timed perfectly.
I can’t say for certain if it was the Timing Belt or the Alternator that was the biggest difference. I feel like the new alternator worked well to keep the battery topped off for better cranking and the timing of the fuel pump helped with the fuel delivery.

 

[radiator]

@Catarinoforlife
If I get you right to time a pump you mean to adjust it in some sort of way, mayby by the vcds software? If so then plz tell me how to do it. I can't see any option under vcds or i may have missed it. I replaced agm 3 yrs ago, serviced motor starter, replaced cumshaft sensor and no luck. And before cleaning crankshaft sensor I had long cranks but not as often as after the cleaning it.

 

[Catarinoforlife]

@Catarinoforlife
If I get you right to time a pump you mean to adjust it in some sort of way, mayby by the vcds software? If so then plz tell me how to do it. I can't see any option under vcds or i may have missed it. I replaced agm 3 yrs ago, serviced motor starter, replaced cumshaft sensor and no luck. And before cleaning crankshaft sensor I had long cranks but not as often as after the cleaning it.

The high pressure fuel pump is driven by the timing belt. When changing the timing belt, the fuel pump sprocket (gear looking thing) needs to be locked at the correct spot when the camshaft/crank sprockets are locked in their positions.

 

[5N2]

struggling continue.......
I found a video on YT where a bloke shows that cleaning the crankshaft sensor resolved long crank issue. So I had it cleaned but the next day long crank was even longer than usual. The problem occurs every morning since than and what is even worse then precleaning. Before the sensor cleaning every second engine run no crank and now no vcds nor on the dashboard errors son no idea what to do now.

I had the same same problems on my Tiguan 2.0 TDI (2017), and after i updated my software the problem was solved.

 

[Dr Lee]

Hi guys, I have the A3 clha 1.6tdi and also have the long crank on cold start. I have done a bit and car has improved a lot.
I have realized as well that the long crank can be caused by different reasons, my car always had this issue from when I first bought it used about 6 years. I am only now this year working to resolve as a few months ago after standing for about 2 weeks it cranked for over 30min before it started and then again was fine. I will share my current ongoing experience and hopefully it helps someone.

1. Battery and registration
2. In tank fuel pump and control module
3. Injectors & fuel return o rings
4. Coolant and cam sensor renewal
5. Tested glow plugs working by measuring amps with amp clamp meter
6. Checked fuel rail pressure above 200bar while cranking
7. Checked starter crank speed at 220r/min.

Ensure your battery is registered on the car as this tells the smart alternator how to charge the battery, the alternator does not output full voltage and amps if it thinks the battery is old. The ecu measures the throughput in amphours, this resets to zero when you register the battery. You will then see up to 15v charging output when the car while braking/coasting, this is not to waste engine power on charging while also calling for engine power to accelerate. There is a electrical shunt attached to the negative battery post that monitors the amp usage and charging(when so equipped). You can unplug this shunt and check that your alternator is charging at 14.4v. The car ecu usually keeps the battery at 80% charge, so as not to waste the available power while braking if the battery is fully charged at 100%. Putting in a new battery without registering it will not work as the ecu will not know. Weak battery or unregistered new battery is a large part of long crank.

I am will next check the injector start quantity on cold and warm start. If the ecu is commanding the injectors to fire, either the quantity is to small for a quick combustion on cold start or the starter speed is too low to generate sufficient heat in the cylinders for combustion with the cold fuel after the car stands for awhile. Also need to check that the throttle plate is not sticking in carbon buildup as car cools.

It could be that the car starts easily when its really cold as the ecu reverts to cold start fuel map(aside from glow plugs), when the car is warm to hot the engine can start easily with warmed up fuel and cylinder walls. Hence its the medium temp zone that gives us the longer crank. Mine is now at 1.5 sec to 2 sec. Other times the car starts in less than 0.5sec.

Also the glowplug light being on or off does not mean that its actually on or off.
Sorry for long first post.

 

[radiator]

Ya have written so much that I can't make head or tail what did (if you did) to improve morning long crank. Ya say what to inspect but plz tell us did ya do anything in specific to solve thal f*king long crank tha ya can share with us an say yes it did solve the problem. We all have been going through the straggling with long crank, have our own points but our eforts still in vain.

 

[Dr Lee]

Ya have written so mach that I can't make head or tail what did (if you did) to improve morning long crank. Ya say what to inspect but plz tell us did ya do anything in specific to solve thal f*king long crank tha ya can share with us an say yes it did solve the problem. We all have been going through the straggling with long crank, have our own points but our eforts still in vain.

So yes I did all the above and the items that specifically reduced the long crank where:

1. new battery and registering it on ecu-I also replaced a year ago but didnt register it and it lasted less than a year. Starter must crank fast enough to compress the fuel in cylinder to generate sufficient heat for diesel combustion.

2. replaced in tank fuel pump-there is no more a pressure sensor on low pressure fuel side(so no fault code), I bought a 10bar gauge on amazon and tested until I confirmed no fuel at fuel filter. The weak point that fails is the relief valve built into the pump. The motor itself is a 3phase brushless electric dc motor that lasts forever. So its an intermittent problem that shows itself only when you have the car standing for some hours. The fuel pumps back into the tank through the pressure relief valve,not to engine.

3. replaced 4 injectors- removed the fuel return line and found fuel returning while cranking, I removed and tested at a bosch centre and found no.3 had high return pressure. This was also intermittent fault, so difficult to diagnose and catch.

I have tested by standing the car unused for up to 2 weeks and 90% it starts within 0.5 sec. 10% it takes about 1sec, longest it takes is 2sec after the above changes. I will try to find the videos I saved of starts.

 

[Funguy]

Looks like there is no consensus on a solution for the long crank issue. I just inherited my father's 2015 Sportwagen which seems to have this long crank issue. Dad's is an SEL with the larger, 18", wheels and tires.
I have just started to check mpg but, (the SEL with 18" tires and long crank) seems to get substantially less mpg than my other 2015 SportWagen 'S' which has 16" old snow tires on it and never has long crank times. Hmmm?
Also, that this seems to be a warm weather issue according to a lot of posters in this thread, has to be a big clue???

 

[Nuje]

Not to derail the thread, but I just switched to slightly oversized 15" (205-65-15) tires from 17" and was kinda wow'd at the improvement in fuel economy. Roughly 7% better. Which isn't gonna allow me to buy an RS6 Avant or anything, but it was a lot more than I was expecting.

I highly doubt that the tires relate to the long-crank issue, though.

 

[drewpul]

Car and Driver did a comparison of MPG and performance on a Golf back in 2010: https://www.caranddriver.com/features/a15130598/upsized-wheels-tires/

 

[Nuje]

Good info - thanks for posting/linking to it!

The other thing I've noticed, having put direct TPMS sensors into both sets, is that the CrossClimate2 17" must get a lot hotter because even on cool days (15°C = 60°F) they'd go from cold 38psi to 42psi within maybe 10min; and on hotter days would hit 45psi. Maybe I should be putting more air in them (?).

The 15" Michelin Defender, meanwhile, cold inflated to 38psi, struggle to hit 41psi; and on the hottest day I've driven them yet, have only ever hit 42psi.

Long crank discussion....hmmmm......I still notice (as I did probably a few pages back) that if/when I remember to power up the car (hit START without clutch/brake pressed down), and after a few seconds, *then* hit START with the clutch down, it starts up right away. The occasional times I forget, it's about 50/50 whether I get the long crank. Only cold. Hot it fires up right way all the time regardless.

 

[drewpul]

I've learned to live with the long crank. For me, it's literally only a temperature thing. So summer and winter I rarely get a long start.

But in moderate temps of 50s and 60s, long over half the time.

Even if I start it for a min. Shut the car off and turn it right back on, still a long crank. So I doubt it has to do with the fuel pump as the fuel is still alreary primed

 

[Funguy]

Not to derail the thread, but I just switched to slightly oversized 15" (205-65-15) tires from 17" and was kinda wow'd at the improvement in fuel economy. Roughly 7% better. Which isn't gonna allow me to buy an RS6 Avant or anything, but it was a lot more than I was expecting.

I highly doubt that the tires relate to the long-crank issue, though.

Thanks for this comment. I didn't think that tire size affected long-crank issues but was looking for a reason why mpg was so much lower on the long-crank car and whether tire size could explain that much less mpg or if long-cranking was associated with mpg loss.
I am only keeping one of these GSWs so I also need to make sure the lower mpg is not a symptom of something. I am leaning towards Dad's SEL for emotional as well as the bells and whistles that the SEL has, BUT, my S trim car doesn't long crank....

 

[wonneber]

I had the trickle charger on it last night. Didn't make a difference starting it this morning. Still has the long cranking for the first start then perfect afterwards.

Mine sits in a garage so temp stays about 70 to 80 over night. I guess this winter I will leave the car out and see how it starts in cold weather lol.

I don't have this problem but maybe turn the key on, check if the GP light is on, wait 5 seconds (or so) then try starting it.
I think my 2014 JSW starts a bit faster doing this.
Or it could be all in my mind.

 

[wonneber]

I had the trickle charger on it last night. Didn't make a difference starting it this morning. Still has the long cranking for the first start then perfect afterwards.

Mine sits in a garage so temp stays about 70 to 80 over night. I guess this winter I will leave the car out and see how it starts in cold weather lol.

I don't have this problem but maybe turn the key on, check if the GP light is on, wait 5 seconds (or so) then try starting it.
I think my 2014 JSW starts a bit faster doing this.
Or it could be all in my mind.

 

[Nuje]

I am only keeping one of these GSWs so I also need to make sure the lower mpg is not a symptom of something. I am leaning towards Dad's SEL for emotional as well as the bells and whistles that the SEL has, BUT, my S trim car doesn't long crank....

For the seats in the SEL alone, I'd go with that one.
(Not to mention a LOT more creature comforts - climatronic, panoramic roof (just be sure the drains have been clipped), front assist, MUCH better headlights, etc.

 

[Nuje]

I don't have this problem but maybe turn the key on, check if the GP light is on, wait 5 seconds (or so) then try starting it.
I think my 2014 JSW starts a bit faster doing this.
Or it could be all in my mind.

Yep - that's what I was trying to describe above, but using the pushbutton start instead of key in ignition.