Cold Weather Hesitation/Stumble/Knocking, Torque Difference, NO CODES

[Fastbird]

Same issue I've been dealing with for going on my third winter now. Cold start only, very pronounced diesel nailing, and around 1750 RPM stumbling and hesitating, until engine starts warming up.

Car is NOT hard setting any codes. VCDS will show a pending code for "torque difference" on Cylinder 2 (I believe, been a while since I've looked at it). Symptoms are pointing to a failing injector like many other people have experienced.

HOWEVER......the local VW dealership says their computer shows no pending codes and refuses to even try to diagnose further. They test drive and say it's "normal" or check the oil and say it's slightly overfull and causing the problem.

So my question is......what is the threshold for getting that Torque Difference code to hard set? I've driven the car and had the stumbling so bad the car wouldn't accelerate anymore and no code ever hard set, no check engine light.

 

[22eco]

It sounds like the injectors are going bad or at least one. I have dealt with this issue directly. let me guess the issue is only when you first start the car? The dealer cant replicate the issue?

Drop your car off the night before the appointment, leave a note in the car stating for a technician to start the car and drive it right away. They will feel the issue then figure it out from there.

 

[Fastbird]

It sounds like the injectors are going bad or at least one. I have dealt with this issue directly. let me guess the issue is only when you first start the car? The dealer cant replicate the issue?
Drop your car off the night before the appointment, leave a note in the car stating for a technician to start the car and drive it right away. They will feel the issue then figure it out from there.

Done this. They can never seem to replicate or tell me the hesitation/stuttering is normal as it warms up. The techs are full of.....excrement, even the head tech who said there's no way it's an injector, they don't act like that when failing. Whatever. I'm just trying to get the dang code to hard set so their hand is forced into fixing it under the warranty. Problem is they're the only dealership in the area.

 

[06bluebeetletdi]

Drop the car in the dealership parking lot the night before, do not leave your keys, go back in the morning. Insist someone drive it with you with the scan tool connected.

 

[22eco]

That’s what I did, I took it to the dealer like 3 times before they figured it out.. You have to emphasize that they drive it right after they start it..

 

[rmilchman]

I'm having the same hesitation issue. Dealer told me there are no codes and their is nothing they can do until a CEL comes on. I opened a case with VW, and the car goes back tomorrow. There seems to be several threads around the same topic, all of which point to the Injectors.

 

[KERMA]

You won't get a code to set and here's why

The applicable diagnostic routines in the ecu that relate to this condition are not in effect (aka "released") until the coolant temperature reaches 50C. So there won't be any codes set in the ecu when the car is first started and the engine is cold.

You will have to wait until the injector worsens enough so that the torque difference for the affected cylinder is outside the "accepted" tolerance band so that the ecu recognizes the condition while the diagnostics are operating.

If you want to diagnose which cylinder is unhappy, you will need to find the "inner torque" or "internal torque" in advanced measuring blocks, and compare the readings between cylinders. Should be pretty obvious.

Sadly, until there's a CEL, the injectors are technically "within spec", even though teh nailing is irritating.

 

[rmilchman]

You won't get a code to set and here's why



If you want to diagnose which cylinder is unhappy, you will need to find the "inner torque" or "internal torque" in advanced measuring blocks, and compare the readings between cylinders. Should be pretty obvious.

I'll give this information to the dealer when I drop the car off. I'm sure they won't be happy about me doing so.

 

[rmilchman]

Now it's time for the real games to begin. Got a call from the dealer. After working with a VW tech on the phone and running tests the tech recommendation the outcome is to replace the 4 injectors. Since there is no CEL, I'm being told they don't think warranty will cover it (I smell BS). More to come....

 

[rmilchman]

Just got a call back, that VW will cover it. Should be installed on Monday, tested Tuesday morning and hopefully the car is mine again Tuesday night.

 

[06bluebeetletdi]

Great news

 

[Fastbird]

Now it's time for the real games to begin. Got a call from the dealer. After working with a VW tech on the phone and running tests the tech recommendation the outcome is to replace the 4 injectors. Since there is no CEL, I'm being told they don't think warranty will cover it (I smell BS). More to come....

Just got a call back, that VW will cover it. Should be installed on Monday, tested Tuesday morning and hopefully the car is mine again Tuesday night.

Sent you a PM.

 

[Mikestdi]

Dropped my 12' at the dealer this past Friday for the same issue. Although, I did have a pending P1007 Torque Difference Cylinder 4 code. I have about 1400 miles left on the 4/48 warranty, fingers crossed.

 

[06bluebeetletdi]

Dropped my 12' at the dealer this past Friday for the same issue. Although, I did have a pending P1007 Torque Difference Cylinder 4 code. I have about 1400 miles left on the 4/48 warranty, fingers crossed.

Did you get the letter extending the warranty another 3,000 miles? I received one for my Passat.

 

[Mikestdi]

Nope. Did they say what the extension is in reference to?

 

[06bluebeetletdi]

They added 3 months/3,000 miles to the emissions warranty for generation 2: https://www.vwcourtsettlement.com/w...ssions_Modification_Disclosure_Volkswagen.pdf

 

[Mikestdi]

Picked up the car tonight, new injectors installed under warranty. Problem fixed!

 

[Fastbird]

FINALLY!!!!!! The problem has been getting MUCH worse as of late. Ran a quick errand today and not even 10 minutes after I left home the CEL came on.

P1007 Torque Difference Cylinder 4 - Limit Value Exceeded - MIL ON

Called the dealership, have an appointment to drop the car off on Friday. Told them that the CEL is on this time and I'm officially punting it to them to fix rather than give me a "nothing is wrong" or "the shudder is normal" diagnosis.

 

[Fastbird]

Well.....imagine that. Diagnosed at the dealership today as a bad Fuel Injector. Left in a 2019 R Line Jetta as a loaner (gasser). All covered under warranty.

 

[Fastbird]

Happy to report back that after a couple of weeks with my car back, it drives exactly like it did when I purchased it back in 2015. Smooth, no jerking or hesitating, no overly loud diesel sounds or knocking, just smooth and refined again.

Went over the receipt from the dealer and man, they really do everything they can to get out of paying the warranty on it. "Performed test plan, collected fuel sample, density tested 13, good. Performed sniff test and checked ok. Tested fuel back pressure, fuel pressure return-all good. Recommend replacing Cyl 4 Injector." I get part of that would be emissions warranty coverage, but the other part is just looking for any excuse to get out of paying. Logic would dictate if it was bad fuel.....wouldn't ALL injectors be on their way out?

Anywho, it's fixed, and I'm happy with it again.

 

[overseasSoul]

Adding to this thread to confirm exactly the same issues and their resolution. My 2012 Passat TDI with 187,000 miles showed the same cold start hesitation, misfiring and knocking for the first 3 minutes or so until it warmed up. I tried cleaning the injectors with a Liqui Moly diesel purge, but in fact, with the Liqui Moly diesel tank additive, the knocking got worse and the ECM threw a code "Torque Difference Cylinder 2" with the engine jerking about in its knock and misfiring.
Read this thread and realized that I still had some of the VW settlement warranty left on the fuel system, so I took it into the dealer. After a bit of back and forth, I was able to force a cold test drive and demonstrate the problem to a service guy. They called me back and said the car had failed a "diesel fuel quality test", but if I paid for a new fuel filter and draining the tank, they would replace the injectors under warranty. They did, and it solved the problem. The diesel fuel work cost $441, which I considered a scam, but I had no choice.
Great news is I have my beloved Passat back and running really well. Thanks to this forum - i was tearing my hair out worrying about getting this fixed.

 

[IISIlKYII]

I have this same issue @ 152k Miles.

P1006 code cyl 3 torque difference.

Most likely replace all the injectors since in there to begin with.

 

[22eco]

Just got a call back, that VW will cover it. Should be installed on Monday, tested Tuesday morning and hopefully the car is mine again Tuesday night.

Awesome.. I had the same problems with the dealers.. first they were only going to replace one, once they got the new one in and they realize the others were bad too so they replaced them all.. two weeks later I get the car back been running like a champ ever since..

 

[Brad95]

injector noise?

2015 TDI having similar problem nailing sound when it's cold, once warmed up nailing/knocking goes away. it's not throwing any code.


FF, oil & filter service just got done did put diesel purge in fuel filter it relieved somewhat or just a placebo don't know, noise is still there. always filled up @ high volume station like chevron or shell, used Standyne performance additive at every fill up, now using PS silver bottle.



i tried checking deviation quantity (+2.2 -2.2) when idling in the morning but got confused, sometime #1 injector looks faulty some times #3 & #4. i think i am not using VCDS right. deviation numbers on VCDS screen window keeps changing. based on my reading here one has to check in the morning while idling but what is the proper way to average it out?

-thanks

 

[DeepGunSix]

Here I go again!

Last year I was having the tell-tale signs of an injector(s) failure. Significant knocking sound, stuttering, lurching back/forth, etc. The problem got so bad that my 2013 Passat TDI (certified w/ warranty) wouldn't shift to a higher gear without having to oddly manipulate the throttle. This problem would "fade" as the car reached operating temperature. I took it to the dealership on 3 separate occasions to have it analyzed and each time they came back and said they "couldn't replicate the problem". However, the service technicians were starting my car and letting it idle for a good period of time before test driving, which the dealership freely admitted. I was told that there appeared to be nothing wrong and I was hearing normal diesel engine sounds.

I then started recording the problem on my phone. I'd capture the current mileage, start my car, and immediately drive it. I recorded all of the cars behaviors on video, showing my cluster gage while also capturing video and audio of the road while in transit. There was no denying it, my car was clearly having issues! The knocking was loud and clear and my tachometer was acting sporadic. I emailed my videos to the service manager at my local VW dealership and requested a "received email and read email receipt" to be certain that he indeed got them. He did, and he had me come in again.

Onto my fourth visit to the service department I was upset. I told them that I was losing faith in their ability to diagnose my engine issues and that they must start my car and IMMEDIATELY and drive it. No waiting at all. Start and GO! The next day I got the call from the VW service department. They "discovered" that I had injector issues! Well, how about that? However, they only replaced 1 of the injectors (under warranty).

Before returning the car to me the service manager said that he took it for a test drive and he heard additional "knocking noises" and he felt that additional injectors may be going bad as well. Apparently he was told by VW that they (VW) would not allow his service department to replace the remaining 3 injectors unless they showed data on a service monitor that was beyond a certain threshold of performance issues? I understood this to mean that even though the injectors are not ideally operating, there is a margin of error that VW feels is acceptable for the injectors to be within?

Within 1 mile of picking up my Passat I was hearing the same sounds as I previously was. Yet, the other injectors didn't merit replacement because they were not operating outside of a "threshold?" I'm months into it and my Passat is back to behaving just as it was before they replaced one of the injectors.

I see in threads that some people who have experienced this problem had all four injectors replaced. And there are some who only had one or a couple replaced. Does anyone have any advice on how I should handle this problem moving forward? I'm under warranty for another 8 months. I want to have these injectors replaced/fixed once and for all and not have to come back once I'm out of my warranty.

*I bought my certified 2013 Passat TDI from the VW dealership after it had all the "emissions reprogramming" performed due to the lawsuits the VW had.

Any input?

 

[rmilchman]

I called VW directly, they had someone from corporate work with the local mechanic and determine I needed all 4 injectors.

 

[DeepGunSix]

I called VW directly, they had someone from corporate work with the local mechanic and determine I needed all 4 injectors.

I will give them a call directly! Thank you for your advice!

 

[AverageAndy]

You might want to check out this thread before replacing the injectors...

2013 Passat stumble I've researched for weeks...

Hey everyone, I have a 2013 Passat TDI with 75,000km Problem started only on a cold start (summer temperatures). It idles perfect, reves perfect, when I put it in drive and accelerate to more then 20kmh it will stutter and knock and hesitate. After about 1 minute it's all gone and drives...

forums.tdiclub.com