Rough Idle

lmrjlr

Member
Joined
Sep 21, 2008
Location
Leonardtown Maryland
TDI
2000 Beetle and 1998 Jetta
After replacing the seals on my injection pump I am experiencing a rough idle. The car runs fine during normal driving speed. I first I suspected dirt in the lines or injectors so I added some injector cleaner to the tank but it did not help the situation.
Has anyone had any experience with changing out the Engine Speed Sensor? Could this be the problem? Or do I need to clean the Inector?:confused:
 

TonyJetta

Top Post Dawg
Joined
Sep 15, 2005
Location
Tucson, Az
TDI
'15 Jetta TDI SE / '06 Jetta TDI DSG Pkg0 / '96 Passat TDI
The crank position sensor rarely fails. When it does, the engine won't start.

Which car are you referring to?

What is your IQ set at? i.e. Injection Quantity?

Tony
 

rackaracka

Veteran Member
Joined
Nov 15, 2001
Location
Monroe, NJ
Need more information... Did You change the seals or did You have a trusted mechanic do the work? Did they or do You have a VCDS to read the IQ (Injection Quantity) and then re-set the proper values with mechanical adjustments to the head? Was the IP removed fro the car?
 

lmrjlr

Member
Joined
Sep 21, 2008
Location
Leonardtown Maryland
TDI
2000 Beetle and 1998 Jetta
[FONT='Verdana','sans-serif']I changed the seals out myself. I did not remove the Injection Pump form the car. I did the seals on my 98 without any problems so I thought I would not on this one. Looks like the same pump to me. No I do not have a VCDS. I did it according to the instructions on the sight.[/FONT]
 

jetta 97

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Joined
Dec 25, 2008
Location
Dallas (McKinney) ,TX ,USA
TDI
2 X Jatta MK5 2006
lmrjlr said:
[FONT='Verdana','sans-serif']I changed the seals out myself. I did not remove the Injection Pump form the car. I did the seals on my 98 without any problems so I thought I would not on this one. Looks like the same pump to me. No I do not have a VCDS. I did it according to the instructions on the sight.[/font]
This is common problem when you do pump seals with out VCDS and taking IQ volume before replacing seals. Most likely you have low IQ and you need to adjust it. Only way to that is with VCDS (VAG-COM).
I bet you in cold morning is getting worst, then when engine get hot it get little better.
 

Dodoma

Veteran Member
Joined
Mar 30, 2004
TDI
2002 Jetta White
Why would you need to adjust IQ volume when the pump was not distrubed?. Moreover, Imrjlr did the same procedure before without problem. See if replacing the filter helps. Also, if my understanding is right, the ecu determines IQ volume based on other parameters.
 

TonyJetta

Top Post Dawg
Joined
Sep 15, 2005
Location
Tucson, Az
TDI
'15 Jetta TDI SE / '06 Jetta TDI DSG Pkg0 / '96 Passat TDI
Dodoma said:
Why would you need to adjust IQ volume when the pump was not distrubed?. Moreover, Imrjlr did the same procedure before without problem. See if replacing the filter helps. Also, if my understanding is right, the ecu determines IQ volume based on other parameters.
Read the FIRST post:
After replacing the seals on my injection pump I am experiencing a rough idle
He needs to check the IQ and adjust via hammer mod.

Tony


 

jetta 97

Vendor
Joined
Dec 25, 2008
Location
Dallas (McKinney) ,TX ,USA
TDI
2 X Jatta MK5 2006
Dodoma said:
Why would you need to adjust IQ volume when the pump was not distrubed?. Moreover, Imrjlr did the same procedure before without problem. See if replacing the filter helps. Also, if my understanding is right, the ecu determines IQ volume based on other parameters.
Because he did upper seal and when you move that even if you make mark on pump you will have to adjust IQ.
Movement is in micro mm, so you can't see with eye. That why you need take IQ volume before you replacing seals to know how much you need put back when you replace seals.
I did a few ,and newer have been able to put it back same way that it was. I had to adjust with VCDS, or hammer mod.
 

lmrjlr

Member
Joined
Sep 21, 2008
Location
Leonardtown Maryland
TDI
2000 Beetle and 1998 Jetta
Just to let everyone know I did get the rough Idle fixed with the Hammer and wood block method. I did it with the engine running. I do not own a VAGCOM and I am sure it is not perfect but it is 90% improved. Before this my idle speed was around 1100 and rough. now it is around 750 to 800 - and smooth idle. Who would have believed that a ball pein hammer and a 4x4 wood block could fix my problem. Thanks again.
 

egibbys

Veteran Member
Joined
Feb 20, 2008
Location
Salt Lake City, UT
TDI
1999 Jetta TDI GLS
TonyJetta said:
That RPM is a little low. Spec is 903.
Perhaps he is guessing about where it is since he doesn't have VAGCOM. Although I was unaware that the hammer mod messed with the idle speed. I have done this to my car and my idle was unaffected.

My idle used to sit at 903 rpms and then drop to 840 after sitting for 10 seconds. This made my idle very rough and not tolerable. I used VAGCOM and raised the idle to around 990rpms. Don't know if this is recommended but it helped smooth out the idle a bit. It also got my IQ to stay in one place. When the rpm drops the IQ bounces a lot. So lets say its at 4.0, it would bounce from 3.8 - 4.6. Just all over the place. Now it tends to vary only by 0.2. My IQ is currently at 5.0.

I've been told that the fuel quantity adjuster is warn out inside the pump. Does that sound right? I was told that the only way to fix the problem was to get a new pump.
 
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NB_TDi

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Joined
Mar 16, 2008
Location
NB, Canada █♣█
TDI
2014 Jetta SE
The mod does not affect the idle, but fuel will.

The pump may wear, but you can adjust it doing the mod. There should be no need to replace the pump unless you can no longer get it to stay in spec.
 

egibbys

Veteran Member
Joined
Feb 20, 2008
Location
Salt Lake City, UT
TDI
1999 Jetta TDI GLS
Are you refering to the timing? Cause its pretty close to "within spec". It bounces in and out of the area on the graph. Its just a little low. The mechanic says he can't get it any closer.
 
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