2002 vw jetta tdi rpm varies while about 100 rpm

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
Hello every one I am new to this forum, i am having little issue with my tdi, rpm varies up/down 100rpm while coasting down the road and i can feel the car pull little bit, i changed the duel filter, i changed the MAF, and right now I am not sure what to look for next, any help would be appreciated thanks,
 

jmodge

Top Post Dawg
Joined
Jun 18, 2015
Location
Greenville, MI
TDI
2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
Sounds like at idle? Check your temp sensor with VCDS. I had a slight hunt at idle with a bad sensor before
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
It idles perfect, just when driving at any speed, it will start to move up and down

Car is automatic
 

flee

Veteran Member
Joined
Sep 19, 2011
Location
Chatsworth, CA
TDI
2002 Jetta GLS wagon
This could be transmission related, maybe the torque converter locking in and out.
I have noticed this mostly under load on a failing 01M trans.
When and how often was the trans fluid changed?
 

STDOUBT

Veteran Member
Joined
Jul 30, 2007
Location
Portland, effing Oregon
TDI
dos jettas
You say you can feel the car pull a little bit. This is without pushing down the go pedal? I wonder if the engine is starting to sip on intercooler oil.
My first step would be to make sure the intercooler piping is clear of puddles....
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
It only happends when i hold steady speed or if i cruise it. I am not sure when transmission oil was changed as I just got the car few weeks ago.
how do I check if there is oil in the intercooler?

I have a video is there a way I can post it somewhere?
 

STDOUBT

Veteran Member
Joined
Jul 30, 2007
Location
Portland, effing Oregon
TDI
dos jettas
Mileage?
For the 01M, you for sure want to keep the gear oil as fresh as possible.
A lot of people recommend installing a cooler on that tranny to prolong its life. Tons of info about the 01M here.
Most people link youtube to demo stuff here.
There's also a ton of intercooler videos on youtube. Just search ALH intercooler.
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
Car has 132k miles, transmission shift great, i will be checking intercooler tomorrow for oil, i only have check engine light for glow plugs which is my next project but as it looks like it's harrness.
 

Powder Hound

Top Post Dawg
Joined
Oct 25, 1999
Location
Under a Bridge, Crestview, FL, USA
TDI
'00 Golf 4dr White 5sp, '02 Jettachero 5sp, Wife's '03 NB Platinum Gray auto(!)
Do a search on Coolairvw's threads on the 01M transaxle. It will help you figure the unit out. You'll also need a VCDS to do proper diagnosis, but on the surface, it sounds like your valve body needs help.


Go read those threads and do some thinking, and testing. At least, what you can do. If you can find someone with a VCDS who is willing to help you out, or if you can go buy your own (see the Ross-Tech website) then by all means, DO IT!


Good luck,


PH
 

flee

Veteran Member
Joined
Sep 19, 2011
Location
Chatsworth, CA
TDI
2002 Jetta GLS wagon
It only happends when i hold steady speed or if i cruise it. I am not sure when transmission oil was changed as I just got the car few weeks ago.
how do I check if there is oil in the intercooler?
I have a video is there a way I can post it somewhere?
What you describe is exactly the way my 01M was acting.
It was the TCC failing to hold. Eventually it did throw a CEL.
A fluid change helped a little bit but did not solve the problem.
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
I was suspecting valve body from online what I was reading, i am going to try changing oil in tranny, see how it goes, have any body tried valve bodies from ebay
 

Powder Hound

Top Post Dawg
Joined
Oct 25, 1999
Location
Under a Bridge, Crestview, FL, USA
TDI
'00 Golf 4dr White 5sp, '02 Jettachero 5sp, Wife's '03 NB Platinum Gray auto(!)
a valve body from ebay - hmmm.... check my sig. Ebay would be good for some kinds of bling or other peripheral stuff, but for a valve body in the transaxle, I think it would be a better idea to go to someone like coolairvw who will stand behind his product and with whom you have an outstanding chance of getting things going again.


I just don't know about what I'd be getting off ebay.


How risk adverse are you?


Cheers,


PH
 

KyleMillione

Veteran Member
Joined
Jan 27, 2017
Location
Yaphank, New York
TDI
02 Jetta, 03 Jetta
Your valve body is probably toast. Id check how burnt the fluid is before spending $ on a valve body, if it's black, your probably sunk. Also, time is of the essence, the more you drive it surging, the more your abusing the TCC. I have had this one (https://www.ebay.com/itm/361599208451?ul_noapp=true) in my car now for about 30k, and it seems to be holding up. I agree that coolairvw is the guru on these things, but couldn't justify spending real money, because if it didn't work it was getting replaced with a working unit harvested from a car I crashed. Theres a lot of things that makes these "rand-o-fail" transmissions upset, I find that the normal fill procedure leaves it about 1/2 qt low. Also, tire pressure greatly effects shift quality, if one tire has more air it will bang into gear. If you have VCDS I recommend turning off the DSP and coding it into sport mode. If I was in your position and the fluid isn't black, id put that valve body in, fill it with maxlife atf (I've had good results with it), recode it, and see if it learns.
 
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Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
I also noticed today when I was driving that when rpm is jumping and i push really good on gas and let go rpm stays like at 2000 but when it's working properly and i push on the gas and let go rpm falls back down to idle
 

KyleMillione

Veteran Member
Joined
Jan 27, 2017
Location
Yaphank, New York
TDI
02 Jetta, 03 Jetta
The hang up on coasting is normal. It is supposed to stay locked up even while coasting. Essentially the motor drives the trans to get up to speed and the trans drives the motor while coasting in 3/4 gear.
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
I am trying to scan codes on the transmission but i can't connect to tcm, i tried with vagcom and with odbeleven. Any ideas
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
Not genuine Vcds but my ODB eleven is genuine and still no connection, but i was gonna go to pull and save and find one there just to try it out, do i need to be looking for specific numbers
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
Ok everybody today i replaced my valve body from one that I got on eBay (said it was rebuilt, tested, and cleaned and shipped also came with its own harness ) got it on Friday I installed it today got four codes for all solenoid, after clearing code for solenoid kept coming back, also transmission was in limp mode and wouldnt come out, started in third and that's was it, well after I talked to ebay I am sending that one back, in mean time i installed my back and Tran oil got changed twice in 2 hours total of 7qurts maybe more, and as of right now there is no more surging, and car pulls great and no trans codes... Will see how it goes, my next plan is to change the oil again next weekend..
 

jokila

Vendor
Joined
Dec 3, 2004
Location
Houston, Texas
TDI
2003 Jetta GLS, Manual
Ok everybody today i replaced my valve body from one that I got on eBay (said it was rebuilt, tested, and cleaned and shipped also came with its own harness ) got it on Friday I installed it today got four codes for all solenoid, after clearing code for solenoid kept coming back, also transmission was in limp mode and wouldnt come out, started in third and that's was it, well after I talked to ebay I am sending that one back, in mean time i installed my back and Tran oil got changed twice in 2 hours total of 7qurts maybe more, and as of right now there is no more surging, and car pulls great and no trans codes... Will see how it goes, my next plan is to change the oil again next weekend..

-1 for not listening to the advice on this thread about the ebay valve bodies.
+1 for another lesson in the school of hard knocks, ahem.. wisdom of life.
 

Suadwa

Member
Joined
Jun 12, 2018
Location
Spokane wa
TDI
2002 VW Jetta Tdi
Yes very true about listening, but i figured I try, and seller offered to send new harness and solenoid but i was upset that, in the ad it say that it's rebuilt, tested and removed and cleaned, and at the end there is issues with it..
 
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