[video] ALH Rough idle, IQ jumping around

jorioux

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2013 Touareg TDI
A couple of months ago I noticed a rough idle with RPM jumping from ~880 to ~930, and IQ jumping from 6 to 8 (see video), but it was only occasional.

But this week, whenever Im idling, its always rough! Except when I give a quick blip on the throttle, the idling returns to normal for a couple of seconds, then its rough again.

Whenever I apply throttle, its all smooth. The rough idle only starts a couple of seconds after being idle.

On the video, the rough idle starts suddently at 15 seconds. You can also hear it, and inside the car, it shakes a little bit.

VIDEO: https://goo.gl/photos/BCafRcTeTgraArsf8

In case it might help, here is another video showing the MAF values: https://goo.gl/photos/VZXWmGzZJPRKG8vi6
 
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UhOh

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Can't watch the video (don't have the bandwidth), but this seems to sound like a failing IP or some bad wires in the IP wiring harness.

Search around for a thread by "ILL_NAMED," he had a VERY lengthly battle with a similar situation and it ended up being chafed IP wires inside his wire loom. These cars are aging and the wiring's insulation is breaking down.
 

jorioux

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Sorry for the delay, but I think the cause is a leaking injector. When I start the car, there is white smoke from the exhaust.

Do you think that could be the cause of my rough idle?
 
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Ill Named

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I doubt it. That is either your timing off or one or more of your injectors leaking down into their cylinders while the car sits for a while. If the timing is off, I'd think that it would start rough.

Did you check the wiring?
 

jorioux

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2013 Touareg TDI
I did check for any wire damage to the IP but everything looked fine.

I changed the timing belt at a vw specialist last summer. When I start the engine, it always starts instantly even during the winter.

I will check the timing with vagcom and post the results.
 
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jorioux

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I doubt it. That is either your timing off or one or more of your injectors leaking down into their cylinders while the car sits for a while. If the timing is off, I'd think that it would start rough.

Did you check the wiring?
That's what I said, I suspect a leaking injector. How can I test my injectors?
 

UhOh

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What's Group 013 look like? You may try to isolate via swapping around injectors to see if the problem follows the injectors or stays at the cylinders.

I'd still lean toward this being an IP issue. I think that if the injectors were messed up (or cylinder problems- low compression, that starting wouldn't be as brisk as you say it is).
 

jorioux

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What's Group 013 look like? You may try to isolate via swapping around injectors to see if the problem follows the injectors or stays at the cylinders.

I'd still lean toward this being an IP issue. I think that if the injectors were messed up (or cylinder problems- low compression, that starting wouldn't be as brisk as you say it is).
Here is the video showing Group 013 (i opened the window so you can hear the random engine studder):
https://youtu.be/UTiRyJYdb5A

And here is the video showing the TDI-Timing graph:
https://youtu.be/WqEbP6dNmwY

You can also notice the camera shaking when the studder happens.
The issue is present whether the clutch is depressed or not, and whether the engine is hot or cold.

Though, I noticed the engine studders a lot more while im braking abruptly to come to a stop (ie.: stop sign or red light)

Here is a screenshot of the scan for CEL:
http://i.imgur.com/wcWCdbB.jpg

@Ill Named
I checked the wiring thoroughly, but if it were a wiring issue, wouldnt I get a CEL about implausible signal or short to ground? Honestly I really checked all the wiring running from the IP to under the battery tray. I even let the engine running while I wiggled all the IP wires one by one and nothing happened.

What should I do ?
 
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UhOh

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Yes, I think that you should get a CEL if there's a wiring issues.

Group 013 seems OK.

Timing, while moving around a bit, appears to be OK.

I noticed that you didn't have the engine up to operating temp. This is important.

Are your radiator fans coming on? (shouldn't given engine temp around 61, but I still want to know) My wife's car had this horrendous shudder at idle that took me the longest time to track down. Turned out the small radiator fan had a chunk missing from the outer ring. When that fan kicked on and you were at idle (our cars don't idle much, and here it doesn't get all that warm) is when it would happen.

Does this happen when idling and the engine is cold, cold?

IP temperature sensor?

ASV messing up?

Clutch?
 

Ill Named

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I had 4 wires rubbed through and no CEL. Your symptoms sound very familiar to mine, but you say you checked the wiring, so I guess that it can't be the issue. Pop the top off of the pump and check for schmeg in there. Pull the little case pressure relief valve and see if it is still in one piece. There is also another valve that is on the front of the pump that can only be changed by pulling the pump off, I can't recall it's name. But if it fails, it'll exhibit the same symptoms as you are having...
 

Ill Named

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Does it shudder while the car is moving? Mine would shudder and stumble when cruising at a constant speed, but was fine when accelerating.
 

jorioux

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2013 Touareg TDI
Does it shudder while the car is moving? Mine would shudder and stumble when cruising at a constant speed, but was fine when accelerating.
As soon as my foot hits the throttle pedal, the engine stops studdering. Whether the car is cruising or accelerating, all is good, no studder at all. Even if I apply full throttle, there is not a single studder.

@UhOh, I don't think it's the fans because the issue happens whether the fans are running or not.

Also, the issue is present wheter the engine is freezing cold or after-30-miles-of-highway hot.

I will check the IP as stated by ILL NAMED
 
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whitedog

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How about starting by setting the IQ down to about 4? This is done with the hammer mod.
 

BobnOH

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central Ohio
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Good idea. Remember to set the adaptation back to 32768(?) default before hammer mod.
 

Perfectreign

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One more thing to check - I had this symptom for about a year. Turned out my IP was failing. Replaced it and my idle is fine.
 

jorioux

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How about starting by setting the IQ down to about 4? This is done with the hammer mod.
All right, so this weekend I tried to take the IQ down to 4 as recommended by whitedog. I have been able to take it down to 3-4, but I dont have the security nut socket, so whenever I thightened the nuts, the IQ came back to 5.4. Do you think the IQ being at 5.4 could be the cause of the studdering?

Where is a video of the IQ when the job was done (at that time, the engine seemed to have less studder):
https://youtu.be/EZWnfKsVJws
https://youtu.be/jrY7y6XS7w8

Though, this morning the issue was still there:
https://youtu.be/1OA_kKxpE4Y

And with the engine warmed up, it still studders like before. What do you think?
 

jorioux

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Just a quick update...

This weekend I replaced my alternator because it failed, and I ran the engine without serpentine belt just to see if the rough idle was due to something in that area, and the issue was still present.

Also, the studdering killed my tensioner shock.
 

BobnOH

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central Ohio
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New Beetle 2003 manual
Did you experienced engine studder only at idle like I do? Is there a way to diagnose a failing IP from vagcom?
I had that exact symptom, but with a pump code or two.
Turned out to be a nick in one of the wires direct from IP to ECU (#3 IIRC) in the bundle just before it goes under the battery tray. Took an eternity to find that.
One possible cause of this symptom with no code is failing DMF (not real common on the early ones)
 

joewilhite

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what is a DMF, i have a 2000 tdi jetta and I'm chasing a misfire at random . when i cycle the key and restart its ok for awhile. also sometimes when i try to start engine and glow plug light won't come on, a no start. when they come on it starts.
 

whitedog

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what is a DMF,

i have a 2000 tdi jetta and I'm chasing a misfire at random .

when i cycle the key and restart its ok for awhile. also sometimes when i try to start engine and glow plug light won't come on, a no start. when they come on it starts.
DMF is the dual mass flywheel.

Have your codes checked with something more than a basic scanner. VCDS is the prefered method since it will read more than just emissions codes. You can also loosen an injection line nut to determine which cylinder is misfiring, then you can go from there.

You need to change the relay 109.

Honestly, you need a thread of your own to address all of your issues.
 

joewilhite

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TUCSON
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2OOO TDI
dmf is the dual mass flywheel.

Have your codes checked with something more than a basic scanner. Vcds is the prefered method since it will read more than just emissions codes. You can also loosen an injection line nut to determine which cylinder is misfiring, then you can go from there.

You need to change the relay 109.

Honestly, you need a thread of your own to address all of your issues.
yea your right i didnt want to hi-jack this thread. But done all that you going to ask. I'll start new thread
 

jorioux

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Montreal, Canada
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2013 Touareg TDI
Just a quick update here.
I noticed that most of the time, I have no more engine studder when the engine gets to 90c, as opposed to be always studdering when the engine is not at operating temp.

Also, I noticed that the studder is really jerky and rough when slowing down coming to a red light or a stop AND the engine is not a operating temp. When the wheels has completely stopped, the engine suddenly has less studder.

Recently its been the 3rd belt tensioner in 2 years I put in the car because the studdering kills the tensioner shock :(

Can this information eliminate some culprits? What do you guys think?
 

BobnOH

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central Ohio
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New Beetle 2003 manual
.............

Also, I noticed that the studder is really jerky and rough when slowing down coming to a red light or a stop AND the engine is not a operating temp. When the wheels has completely stopped, the engine suddenly has less studder.

......................
These cars have a tendency to do this normally, the IQ drops to zero and they just keep running on motion I guess.
Your stutter at idle issue just makes it way worse.
When I had your issue, it got so bad it would sometimes stall just before it came to stop.
 

whitedog

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jorioux: If you have put three belt tensioners on, it was likely because the alternator pulley had failed.

Also, have you checked your engine temperature with VCDS to make sure that it is reading cold when cold and warm when warm?
 

jorioux

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jorioux: If you have put three belt tensioners on, it was likely because the alternator pulley had failed.

Also, have you checked your engine temperature with VCDS to make sure that it is reading cold when cold and warm when warm?
I would like to bring an update here. I know its been a while but I still have the issue and its truly driving me crazy and im going mad about it because I feel like its getting worst and the studder happens more often.

@whitedog: My tensioner is jumping only when the engine is studdering. When the engine runs smoothly, the tensioner wont jump at all, and also I changed the clutch pulley in between two tensioner failures. So my guess is that the engine studdering kills the tensioner :(

A few weeks ago, I did the hammer mod as recommended to fix my issue (but it didnt) and it ruined my IP seal (a leak appeared). Since then, my alternator failed so I replaced it this weekend together with the alternator pulley because of the fuel leak from the IP. The fuel was dripping on the alternator...

Do you think it might worth it to replace the whole IP to cure my engine studdering issue (though im not sure if it will fix the problem) altogether with the fuel leak issue? Is it one big of a deal to change the IP and do I need special tools? I might as well go grab an IP from a U-Pull scrap yard.

What do you think?
 
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UhOh

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A Malone tune with dynamic Idle will keep your idle up until you're over about 143 degrees (convert for C).

I think that it would be good to see what is happening with QA voltage.
 
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