Flashing Glow Plug Light & Loss of Power...

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
This morning while driving to work I had the glow plug light start flashing and had a loss of power. It was 75*F on this fine July morning, started the car up, seemed a little odd that it turned over a few extra times before firing this morning, but it started fine. Back out of driveway, head down my road towards hwy and everything is fine. I go to pull out onto the hwy and there was an immediate loss of power and the glow plug light was flashing. Press the pedal and nothing. After playing with it a bit and can finally get it up to about 35 mph and that's about it. Decide that since Im only a mile or two from home to turn around. It seemed like the limp mode I had with my previous B5Passat. Press the pedal and the tach shows the rpms increasing but cant hear the engine to tell for sure and I shifted thru the gears and it can barely get out of its own way. I get home, kill it, wait 10 secs, it starts right up and I drive it the 50 miles to work with no issues.

  • Warm morning, 75*F
  • Half tank of fuel with about 300 miles on tank
  • 2015 that I just bought in April with 62k miles now.
I read some of the other threads with the similar symptoms but it seems that there isn't a definitive answer to what causes this (maybe multiple things). I have not had a chance to have any codes scanned yet, may do that on the way home. Just wanted to get something started as a help thread for troubleshooting purposes...
 

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
Car drove fine all the way home. Stopped at a friends place to read any codes. Nothing. No codes detected. Would have thought that with light blinking and loss of power it would have thrown a code, but nothing. Guess have to wait until it happens again...
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
just saying, don't use a crap OBD reader from harbor freight.

Any reader worth it's while will read what is stored that caused a limp mode.
 

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
Ok, didnt drive the car yesterday, but drove it today. Drove about 10 miles this morning and when i punched it to merge onto the interstate traffic the light was blinking again and loss of power. It happened right as i was merging and at the foot of a rather large bridge. Hit the bottom of bridge at 60 and topped he bridge at about 25. Coasted down the bridge and got speed up to 65 and could maintain that until i could find a spot to pull over. Turned engine off, restarted and then drove in to work just fine. Drove it home without issue. I picked up my own code reader that says it is compatible with VW and Passats.



https://www.amazon.com/ANCEL-Diagnostic-Volkswagen-Throttle-Position/dp/B07BS7PDC2


Checked for codes. States that no codes are stored. The one my buddy had was a bosch something or other and it couldnt find any codes, now this one supposedly states that it is for this vehicle and still no codes. Guess ill have to bring with me and catch it in the act of acting up. At least it hasnt left me stranded, yet.


Side note, what is typical engine oil temp? I had the display on most of the way home today and usually i see temp at around 204 or so. This afternoon with outside temp at 89, the oil temp was 212-216. Then right as i was getting close to home the temps spiked to 219-224. Not driving hard, just easy cruising. Could have kicked into a regen cycle on the exhaust, but that seems high to me. Of course the needle gauge never moved from 190.
 

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
Ok, this same scenario has happened again about 10 more times. If hook scanner to vehcile before killing the engine I get P0087 Fuel Pressure Low code. If i kill it, then try to read it, no codes are read. Each time it happens is when there is a demand for fuel, either from me pushing on the pedal or re-engaging the cruise and it downshifts to catch back up to speed. If I stomp it WOT it does not do this. It is only when giving moderate pressure to the go pedal, each time at the most inconvenient time.


I typically just pull over, kill engine, restart, and go about my way. Today it did it, except now I actually have a CEL on the dash. But still no codes read other than the P0087. Ive done some reading and videos, fuel filter? fuel regulator? hpfp failure? I havent even performed my first oil change yet since purchase, they fuel filter SHOULD have been changed then, my intuition is not this, but never know. Ill try to replace this tomorrow and I guess take somewhere to get the CEL code read. Frustrating as I just made my 3rd payment and taking it back to dealer already. Any assistance or pointers welcomed..
 

c3kTDi

Well-known member
Joined
Feb 3, 2019
Location
Undisclosed
TDI
2015 Passat
No pointer to offer, but keep us updated.

You'd think something that significant would be recorded with a code.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
The tank lift pump is most likely your culprit. I by itself will throw no codes, but the low fuel pressure code at the fuel rail is the clue. Its a warranty item but if works at the dealer, vw won't pay. Your description is typical of a failing lift/tank pump. When mine was failing intermittantly, vw no pay, I bought a new one and installed it. Interestingly enough, the new pump has a superceeded part number and is very quiet compared to original pump. Pump list for around 300 but you can find discounted places, but make sure you get the latest version. Call the parts dept and get the correct part number.
When I got the one for my golf, there were only 3 of the new version in the US.
 

Fixmy59bug

Veteran Member
Joined
Aug 1, 2009
Location
Las Vegas, NV
TDI
2015 Passat TDI SE
Its a warranty item but if works at the dealer, vw won't pay.
This is true, If the code is not present when the tech scans the car, Vw can do nothing. They dont know what to look at if there's no codes.

It's like going to the doctor "I think I'm coming down with something, but I dont have a fever and I dont have any symptoms".

If it is an easily repeatable occurence, you can request a test drive with the tech or service manager. That way they can personally witness what is going on and there's no way they can say "It's working normally"
 

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
Ok, went to dealer on Friday. He said he was busy, but would break into the schedule if only to read any codes present. The only code read was the P0087. Even with the CEL vs the Glow Plug lite, the only code was the P0087. He said both lights could be tripped for that code. Here I thought I wasn't able to read the CEL code because I was expecting a different code since I got a different light. Maybe that isn't the case. Anyway, they said they checked for hpfp and no metal present. Good.
Then he checked the fuel filter. Said that while it wasn't bad, there was some gunk present. He changed the fuel filter free of charge. Told me that they have recorded the codes as being present for my vehicle and to let them know if happens again and to bring in next week for appointment. Was planning to bring in next friday. Left the dealer, turned the corner , and immediately got the flashing glow plug light. Turned around, brought right back with it still running so they could hopefully see something different that I cant. Nope. Still the P0087 code only. Killed it and the code cleared and I drove home.
As I got close to home I punched it, yup, glow plug light came on again with limp mode. While it had never happened before with a WOT, now it will. Bad that it still happens, good that I can make it happen on demand if only to demonstrate the issue to the dealer. Will drive it this week to see how it behaves them likely bring in to dealer for further evaluation.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
When mine was intermittantly failing, flashing cel light as well. What you can do is: wait for pump to totally fail leaving you stranded, or fix it yourself as I did. The fact that the part # has been superceeded sort of lets you know VW knows about the pump problem. There is no test for the pump other than that it runs. I know what I would do: disconnect the plug at the pump; select the correct terminals; apply 120vac to the pump; plug wires back on; call roadside assistance to have it towed back to the vw dealer. Pump has now terminally failed.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
Don't do this in a gasser for obvious reasons. Anyone get the new part# for the passat lift pump?
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
The pump sound changed on mine as it was failing, became louder. The new pump was very quiet, almost inaudible with seat in place instead of the the noticeable hum.
 

USMCFieldMP

Veteran Member
Joined
Jun 30, 2011
Location
Fort Worth, TX
TDI
2014 Jetta TDI
Most likely boost related limp mode, best to hook up a vcds cable and investigate.
This is what mine has shown.

- - -

This has happened to me a handful of times. It's typically within 5 minutes of starting the car as I'm getting on the highway. I just cycle the key OFF-ON and it goes away.

I did read it with a VCDS once and I only showed a pending code related to boost pressure; no active code.



My thought on it has been that the turbo is cold and therefore takes longer to spool, but once the exhaust pressure builds up enough to get it moving, it spikes hard. Cold turbo boost gain having more of a exponential gain (right graph below) which is harder to control at its peak, versus a hot turbo which has more of a logarithmic gain (left graph). I haven't logged it to confirm, but this is just my educated guess as a mechanical engineer.

 
Last edited:

Smashed Ixnay

Veteran Member
Joined
May 7, 2010
Location
Auburndale, FL
TDI
2015 Passat TDI SEL
And what is the car doing now? What was issue?

The car has been working fine every since they finally fixed the issue. I did just get a CEL come on, but they are going to replace my adblue tank via the warranty. This has nothing to do with my original problem you are now having.


As far as I know it was a wiring issue coming from one of the dpf sensors that burnt on my hood. Originally they only went about 12” from the sensors, but after more time their they dig down farther and found the issue.


I’m not sure if it’s any help, but you could have your tech call David Maus VW in south Orlando. The rep that deals with warranty stuff is named Michael (Mike). He should have knowledge of the issue.


Everything you are saying is the same issues I had, and it took around 6 weeks for them to finally find and fix the issue. They actually had to fly someone in from VWoA to find/fix it.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
kjndiver, your problem I think is different from Ixnay in the fact you haven't mentioned any burnt wires or sensors.
 

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
Ok, as mentioned previously, I brought to VW on a Friday , by Tuesday I was dropping the car off to them as it was doing this every time I accelerated. I had to really feather the pedal to get going without it going into limp mode and throwing a light/code. Always the same P0087. Got a call on Thursday saying they now think it's the HPFP. Even though he had inspected and didn't see any metal just days before, now he says that he does see metal shavings . They've got a case opened with VW and I should hear back this week. He said it was strange in that this is the first time that he has seen someone still be able to drive it for as long as I did, he said it's usually one of those failures that happens and leaves you stranded as soon as it appears and doesn't go for weeks at a time. We shall see....
 

Smashed Ixnay

Veteran Member
Joined
May 7, 2010
Location
Auburndale, FL
TDI
2015 Passat TDI SEL
Ok, as mentioned previously, I brought to VW on a Friday , by Tuesday I was dropping the car off to them as it was doing this every time I accelerated. I had to really feather the pedal to get going without it going into limp mode and throwing a light/code. Always the same P0087. Got a call on Thursday saying they now think it's the HPFP. Even though he had inspected and didn't see any metal just days before, now he says that he does see metal shavings . They've got a case opened with VW and I should hear back this week. He said it was strange in that this is the first time that he has seen someone still be able to drive it for as long as I did, he said it's usually one of those failures that happens and leaves you stranded as soon as it appears and doesn't go for weeks at a time. We shall see....
I hope that fixes it, but I doubt it. They said the same thing to me at first and the new HPFP didn’t do anything. They even changed the fuel filter and flushed my diesel tank.

I still say it’s an electrical issue coming from the dpf sensors like I had.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
If they found metal shavings in the fuel filter, it probably is from the in tank pump starting to destroy itself, not from the hpfp. Its one item that throws no codes itself, the sensors all do.
 

thundershorts

Top Post Dawg
Joined
Jul 15, 2010
Location
west chester pa
TDI
2015 passat tdi sel premium 2015 golf s tdi gls tdi b5.5, 2002 eurovan,Peugeot 505 td,Citroen cx25 prestige
When VW does the full monty hpfp change it involves cleaning the fuel tank as well...but nothing about changing the lift pump.
 

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
Okay, here goes an update...

  • Dropped car off on Tuesday the 13th....got a call on Thursday 15th stating the hpfp as in previous post. Said it should take a week.
  • The following week I didnt sweat it and allowed them to contact me. Finally on Thursday 22nd they called and said that its all approved and that still working but getting close and should be done sometime after lunch on Friday the 23rd.
  • Get a call on Friday the 23rd about 1pm, said that all work is complete except for flushing the tank and that they were waiting on a pump so they could do this. Then he said that the pump he was waiting on comes from Tractor Supply and that it wouldnt be in until Monday. *** you say? VW is beholden to Tractor Supply to perform work? What makes it worse is that you could throw a rock and hit tractor supply from their lot.
  • Monday the 26th comes and goes without communication. Tuesday...Wednesday...Thursday...so I call today, Friday the 30th. Now theyre telling me that the cam timing sprocket is damaged and has jumped time, which caused a bent valve, which requires a head replacement. ***? Claims previous owner must have damaged the sprocket before and that they just missed it with the CPO Inspection. Says that the sprocket "slips". I asked how i was able to drive the car with a slipping sprocket? Said that because it was "in time" it wasnt an issue, but now it is out of time and slipping. I asked well dont you lock that stuff down so that it doesnt get out of time? Thats the whole point of locking it down (I havent performed this job, but from what ive read it all has to be locked in place so as NOT to lose timing). He claims they did but that it was still the previous owners fault. Hell, when i bought the car it only had 57k, there shouldnt have been a need for previous owner to even mess with timing. The belt isnt long way from replacement at 130k. Also claims that he found all of this out just 5 minutes before i called. Said it will take another week or so to order parts needed and complete the work. They will have had my car almost a month before i get it back.
  • I think they are lieing to me and that they messed up and wont admit it. Hey, you mess up, own up to it, it happens, tell me the truth and ill be ok. But this isnt the first time they lied to me. They lied to me when i bought the car as they failed to inform me it was sent off site to get "touch up paint". That there was nothing wrong with the car, just touch up. Then it was a bumper replacement and would take a week to order. And that the body shop didnt work on Good Friday holiday and the following Monday after Easter. I went to the body shop and saw the car and talked to owner. He said that it appeared that either someone had backed into a pole or the car got dinged in parking lot. Required bumper replacement and body straightening of the rear quarter panel and repainting practically the whole rear of the car. I asked and he said that they worked both Good Friday and the Monday after Easter.
  • So this dealer has lied to me from day one on just about everything. I dont trust them one bit at this point, next closest dealer is 100 miles east or west of me.
  • This whole ordeal is leaving a bad taste in my mouth because 1. I thought VW had a better product than this. 2. Dealer lies to customer. 3. I get it, things happen, own up to it, tell me about it. But when i put 8500 miles on a car, then im told that the cam sprocket is slipping from previous owner damage, and the only thing happen bewteeen then and now is the dealer shop "locks" the timing so they can work on it and then its out of time.....I dont buy it.
  • Im contemplating demanding a new engine at this point.
  • Unless its something MAJOR like this again, I will NEVER bring this car back to Lake Charles VW ever again.
  • Stay tuned for final results....
 

Fixmy59bug

Veteran Member
Joined
Aug 1, 2009
Location
Las Vegas, NV
TDI
2015 Passat TDI SE
[*]This whole ordeal is leaving a bad taste in my mouth because 1. I thought VW had a better product than this. 2. Dealer lies to customer. 3. I get it, things happen, own up to it, tell me about it. But when i put 8500 miles on a car, then im told that the cam sprocket is slipping from previous owner damage, and the only thing happen bewteeen then and now is the dealer shop "locks" the timing so they can work on it and then its out of time.....I dont buy it.
Wow...

I dont even know how to respond. You are just having a **** time with this dealer. It SHOULD NOT be this difficult or take this long to get your problems solved. But I'm just stating the obvious there.

I would like to comment on just the little snippet above. Believe me, I can understand the bad taste you are experiencing, but the problems you are experiencing are not due to a "bad vw product". It is due to a bad vw dealer which Vw has very little control over. You NEED to report your experiences to Vw Customer Care to make sure Vw addresses this dealer. They blatantly lied to you multiple times (Slipping cam gear? What the F??). They damaged your vehicle. Tell them EVERYTHING.

Hopefully, once you get this solved you will see the cars as built by Vw are great little cars.
 

KJNDIVER

Well-known member
Joined
Sep 12, 2010
Location
Lake Charles, LA
TDI
2015 Passat TDI SEL
This dealer is the WORST. Since this last post I have been told multiple times that my car will be ready either tomorrow or in a few days only to STILL NOT HAVE THE CAR. Each time its something different. The excuse now is they sent the wrong parts and the correct one is back ordered. Aug 13 - Sept 11 and still no car, only excuses and lies. I have made contact with VWoA to voice my displeasure. Still waiting.....
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
that just stinks all over, best of luck with VWoA, usually they are in bed with the dealer but it's kinda the only option at this point.
 
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