2014 Jetta TDI Sportwagen power loss hiccup

Hi. I am a newbie and wanted to ask this group about a very perplexing issue I’m having. I live in NW Ohio. My wife drives a 2014 Jetta TDI SportWagen. The vehicle has 52K miles. About a month ago it developed a strange issue when driving at low speeds or higher speeds and letting off the pedal or at a constant lower speed the car will have a momentary loss of power and a quick shudder or hiccup. The glow plug Light will illuminate for a second and go out. There is also an audible click that you can hear from under the dash. No trouble lights stay on. After this happens the car goes back to driving normally. Until the random next time it happens. I have also had it quit in drive thru lines twice and a stoplight once. As soon as it is put into park it will restart as normal. I took it to my local Import shop this am and they replaced the fuel filter and did a manual clean of the dpf. Ran a scan but could not find any error codes. This is very strange as it is intermittent. Does anyone have ideas as to what this could be? My wife is concerned that this is a safety issue. Thanks

Hope the fuel tank is not coated with mold or mildew... my 2014 JSW sat about 2 years as an buyback car and she broke down with HPFP failures F I V E times... from the purchase in late Aug 2018 to Feb 2019... mechanic decided to look into the fuel tank and behold! Fuel Tank was coated with mold/mildew..... so they covered it all from fuel tank cleaning to fuel lines to the HPFP replacement along with the fuel filter canister cleaned out... she had only 20k something miles. I bought her with 20k miles and only lasted 5k miles.....

So have a mechanic check the fuel tank out to make sure its clear.... if she was a buyback car.... if she wasn’t then disregard this.


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That is a very interesting thought for sure. Thank You! So when the fuel filter was replaced they said there was some algae like substance in the canister. They cleaned it out and manually engaged the pump and The fuel looked clear but I wonder if the HPFP is acting up from the mildew in the tank. What were the symptoms you were experiencing? Were they similar to what I am experiencing? I really appreciate the insight!

The fuel filter was changed on 4th HPFP replacement then not even a 1k mile later she broke down and fuel filter was caked up in full! Mechanic couldn’t believe his eye so he went to check the tank and behold!

You got an telltale sign of your fuel filter. Please go and get them check the fuel tank asap.


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Ok what was the signs? When I try WOT, she bogs so bad and chokes then throws glow plug light flashing and goes limp mode and no power at full throttle at 45 mph. So I had to pull over turn her off them restart, glow plug flashing goes away and she runs normally as long as I dont go over 1/2 of the pedal. It was a nightmare. A time bomb to go off at anytime. She died on me completely 4 times after HPFP goes. No warning no nothing. After 5th time, they replaced and did all the work. I went CP3 pump swap and be done with it. Voiding warranty I know.


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We're spoiled with west coast weather, but even here I use an occasional fungicide to make sure nothing builds up. Quality high volume fuel stations are a must IMO. I like Chevron. The little bit extra cost is easily offset with extra cetane (power/mpg) and less water/filter issues. A couple oz. of a good lube type additve helps. Cheap insurance.

It does sound like a fungus really needs addressed not only for safety but HPFP longevity.

hill cresting fuel cutout

hill crest shudder

hiccup

I don't know about the glow plug light also illuminating, but the hesitation/stutter/shudder is a well-documented phenomenon on these cars for at least 2, 3, or 4 reasons. One example is caused by defueling, an ECU managed occurrence that saves fuel. It's most noticeable with light acceleration, especially if cresting a hill (links above). In 3rd gear it's most noticeable for me and it happens everyday at the same place on my drive. Another example is fuel management to help warm up the exhaust early during the warmup cycle. It seems the ECU injects fuel to heat portions of the exhaust to improve efficiency. In my car that also causes a kind of stumble/shudder early when the car is just warming up. Then there are the regen stumbles. All manner of odd running behavior when the ECU takes control to regenerate the NOx filter or DPF.

Bottom line, some odd running behavior is completely normal operation for these TDI cars. After 10-years of ownership and over 175K miles, I say no worries! I love my car, even with the shudders. That said, one of these days, I might try the delete and tune thing. I suspect much or all of the odd running behaviors will disappear.

Ksing44, yep you are right, once you go deleted those annoying behaviors will disappear.

Yep I can confirm all that, my old 2011 JSW shuddered and all the jazz was awful at that until the day I deleted her, she thanked me and ran flawlessly.


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Thanks everyone. Is it also common for these to **** off randomly at a stop light or in a drive thru? It’s happened 3 times in the past 2 weeks. Put in neutral or park, push the start button and fires back up and runs fine. I did confirm today this was not a buyback. It was built in June ‘14 and put into service by previous owner Oct ‘14. I love everything about this except these couple quirks. Although I remember my ‘80 rabbit diesel had quirks. Namely the sucking of engine oil into the intake causing the thing to gain acceleration and run away. Added a baffle called a runaway kit. Problem solved. Lol

dv911sc said:

That is a very interesting thought for sure. Thank You! So when the fuel filter was replaced they said there was some algae like substance in the canister. They cleaned it out and manually engaged the pump and The fuel looked clear but I wonder if the HPFP is acting up from the mildew in the tank. What were the symptoms you were experiencing? Were they similar to what I am experiencing? I really appreciate the insight!

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I'm not saying that you have an algaed fuel system...but IF you have an algaed fuel system, that typically involves every component from tank to injector being replaced to get rid of it. It's really not a common issue at all though, but you can have some fuel from your filter canister tested to be sure.

Thanks to all for the insight but I think we found the problem. I took it to the dealer. The symptom happened for the tech. Job 1 done...They were at a loss so it was elevated to VW Corporate to ask their engineers. The first and only place they suggested looking was at the
Engine speed sensor. The tech pulled off the heat shield and noticed there had been a previous repair. The repair was done poorly and is causing a sporadic loss of crank position causing a momentary loss of power. Most noticeable at lower speeds around 1500rpm when the engine is vibrating the most. Also, all 3 wires were shrink wrapped together which is a no no in the VW tech bulletin. If they are spliced they need to be wrapped separate. This seems to have sorted the issue but didn’t hurt to of course change the fuel filter.

dv911sc said:

Thanks to all for the insight but I think we found the problem. I took it to the dealer. The symptom happened for the tech. Job 1 done...They were at a loss so it was elevated to VW Corporate to ask their engineers. The first and only place they suggested looking was at the
Engine speed sensor. The tech pulled off the heat shield and noticed there had been a previous repair. The repair was done poorly and is causing a sporadic loss of crank position causing a momentary loss of power. Most noticeable at lower speeds around 1500rpm when the engine is vibrating the most. Also, all 3 wires were shrink wrapped together which is a no no in the VW tech bulletin. If they are spliced they need to be wrapped separate. This seems to have sorted the issue but didn’t hurt to of course change the fuel filter.

Click to expand...

Wow! Shame on that mechanic! Super lazy smh


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Hello everyone. Back again. This issue is getting very frustrating. The wires to speed/camshaft pos sensor were fixed. Didn’t fix the issue. VW engineers wanted to replace the HPFP on their dime. Didn’t fix the issue. VW engineers then decided a full set of injectors were needed so those were installed today on their dime. Didn’t fix the issue. Not sure where to go next other than electrical. I suggested replacing the speed/cam pos sensor itself as I wonder if that could be an issue. VW May want to replace the engine wiring harness but it may be a fight to get VW to pay as their prerequisite is pulling a fault code and I have none. Seems stupid that they wouldn’t pay at this point. They’ve already dumped $3-4K in parts and labor into the car on their nickel. Thoughts on whether we’re on the right track? It is pretty clear it’s not fuel. Thanks

could it be an ECU issue?

That’s a good thought. I mentioned that to the dealer. So the update from the VW engineers today is they want the service tech to go through the egr and dpf systems and if needed replace any parts. They are wondering if that system is causing a stutter and periodic stall when stopped. VW is still paying the bill. As the regional tech put it, these engineers are determined to fix the issue. Thank goodness for the diesel extended warranty....

tjg said:

could it be an ECU issue?

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I'm experiencing the same exact issue and considering going straight to ecu to avoid the blunders..