Frequently asked Questions

dieselbill

Well-known member
Joined
Sep 29, 2004
Location
Maine
TDI
2015 Passat SE TDI 6 speed sedan Titanium Beige and 06 Jetta Sedan TDI 5 speed Wheat Beige
Re: Boost Pressure Control Valve

My 97' Passat TDI has an apparently stuck boost pressure control valve and the VW dealer wants to replace the whole turbocharger assembly. There must be a better way! Cannot buy BPCV from VW or anyone else? Would appreciate ANY suggestions. Lobstabill
 

XMass

Member
Joined
Jan 18, 2005
Location
Oxford UK
TDI
B4 Z1 1.9TDI Passat 1996 (P) Green
what about a series of more specific how-to-do-it?

Would it be possible to create a series of how-to-do-it FAQ's based on the knowledge contained in these pages. I know that you have general FAQ’s and they certainly give an overview, but when I do a search I tend to find much more specific information about how to solve or do X

So just from reading the forums I now know - for example
a. About cluster problems, what to look for and how to fix them i.e. get an optima red top battery (or I could try and crack it open and get the board resoldered)
b. How to get the best from my brakes
c. That if I start to have ECU problems I should swap out the vacuum hoses (possibly including the one inside the ECU, or if I’m (lucky?) that I should see if I can get a free manifold fix along with a new ECU.
d. That I may well have MAF issue’s
e. That I should change out my power voltage regulator before it goes wrong
f. etc
It would be good if there was a more specific this is what your going to need – this is what you ‘probably’ will need to do. I'm only mentioning this in passing, I don’t know enough to do a FAQ myself, nor do I have the board access to do it but you guys know tons and it would be wonderfully helpful!!!
 

aussie2005tdi

Active member
Joined
Mar 4, 2005
Location
western australia
TDI
golf, 2005, silver
Re: what about a series of more specific how-to-do-it?

I am only new to the site ,but have found it amazingly informative.It has been constructed in such a way that a new member can quickly(with thought)locate the correct forum,even if there vehicle is not available in the U.S. It probably would help if a member could contact another member that they had met on the forum, without having to clog up the forum eg I met someone on the forum who was buying same car in Western Australia, only way to keep tabs on problems is through forum. This must take up a lot of space. Maybe a quick help on how to set up a hotmail or google email may help them keep it off your pages
 

MichiganMan

Member
Joined
Feb 25, 2005
TDI
1998 Jetta, Red
\'98 Jetta getting \"low\" MPG!!!

I have a 1998 Jetta TDI, and seem to be getting "poor" gas mileage compaired to the norm. I consistently get 40-42mpg with mostly highway drive'n with my cruise set at 78mph... tire pressure is at 42psi on all 4... any suggestions to get the 50+mpg that everyone else is getting????? I've had the car for 3 years...runs perfect otherwise, but is something wrong?
 

Truckeratlarge

Well-known member
Joined
Jun 16, 2005
Location
Kansas City, MO
TDI
Passat, 97, white
Re: \'98 Jetta getting \"low\" MPG!!!

You seem to be getting the mpg of an automatic as opposed to a 5-speed. Which trans. does you car have?
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
\'98 Jetta getting \"low\" MPG!!!

You might want to look at your intake or timing. Timing is more likly to be a small problem, and if you're at the bottom of the "acceptable" graph, you might gain several MPG by adjusting towards the top of that graph.
 

jjudd

Active member
Joined
Feb 8, 2006
Location
Rhome Texas
TDI
'97 Passat
RE:Do I really need to read this.
Man, I'm really glad I read that. VERY INTERESTING as Shultze would say.
THANKS,
JJ
 

Colraindub

Veteran Member
Joined
May 5, 2006
Location
Colrain, Ma
TDI
'97 Jetta TDI
How about some FAQ about Mk3 vs. Mk4. I know I hear a lot of stuff in the performance section, but its all Mk4 Related.
 

ThatRickGuy

Veteran Member
Joined
Apr 1, 2006
Location
Madison, WI
TDI
'06 Golf
Heres a good FAQ question, exactly what cars/years are considered A3/B4s?

N/M, I just saw it int the forum description: "A3/B4 TDIs This is a general discussion about A3/MkIII Jetta/Golf (<99.5) and B4 Passats (96,97) TDI's. Non TDI related postings will be moved or removed."

-Rick
 

BleachedBora

Vendor , w/Business number
Joined
Oct 16, 2003
Location
Gresham, Oregon
TDI
'81 DMC-12, '12 Audi TT 418 hp/383 tq, '08 GL320 CDI 275 hp/448 wtq - '81 Caddy ALH, '04 Golf BEW 2" Lift, '85 HMMWV
A3: 1993-1999 (tdi 1997-1999)
B4: 1993-1997 (tdi 1996-1997)
-BB
 

sauvesun

Active member
Joined
Mar 1, 2008
Location
Manitoba
TDI
2001 Jetta TDI Black on Black leather, 5spd, sunroof, 2003 Jetta Tdi Wagon Black on Black leather, 5spd, sunroof, stock
1995 A3 jetta diesel repair manual????

Hi there, just wondering if anyone can help me with a repair manual for my 1995 Jetta diesel, the car recently had its heater core replaced and i am left with sorting out the electrical nightmare
any leads would be appreciated
Thanks
Rico
 

davebugs

Vendor
Joined
Sep 15, 2003
Location
Pittsburgh suburb
TDI
2001 Golf TDI Automatic, MKIV rear axle bushing install tools
Instructions? - heater core replacement 96 Jetta

Can't find a writeup on this anywhere. I've searched and poked around here and the vortex.

I hope it's not as unpleasant as the 91 Passatt heater core that I did.

Anyone have a link to a writeup here or elsewhere?

Thanks,

Dave
 

cgrillmair

Member
Joined
Jun 19, 2008
Location
California
TDI
1997 Jetta TDI
Intake system leak check?

Howdy

In going through GoFaster's excellent low-power troubleshooting guide, in secion 2d he mentions that the red hose comes straight from the turbo compressor discharge. In 2f he suggests comparing red hose and black hose pressure readings. If these readings are the same, can I assume that the intake system is reasonably unobstructed and airtight at least up to the intake manifold?

Just for background, I just bought a 97 Jetta tdi (somewhere between 100 and 150K miles on it) and have been having an awful time on hills. I replaced the intercooler-ecu and intra-ecu hoses and now the power loss has become intermittant rather than constant. I checked my red/black/blue hose pressures this morning. I don't get instant boost to 12 psi at 2500 RPM and 3rd gear and flooring it, but rather only 9 or 10. I have to wait till I get to > 3500 RPM before I'm getting 12 PSI. Red and black hoses give almost identical results, leading me to believe that most of the intake system is ok. However, my blue hose yields 0 PSI under all conditions. I'm slowly coming to grips with the possiblity that there may be something wrong with the turbo, and why the guy sold it to me at blue book (when all other high-mpg small cars are rapidly increasing in value)...

Carl
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
cgrillmair said:
I checked my red/black/blue hose pressures this morning. I don't get instant boost to 12 psi at 2500 RPM and 3rd gear and flooring it, but rather only 9 or 10. I have to wait till I get to > 3500 RPM before I'm getting 12 PSI. Red and black hoses give almost identical results, leading me to believe that most of the intake system is ok. However, my blue hose yields 0 PSI under all conditions. I'm slowly coming to grips with the possiblity that there may be something wrong with the turbo, and why the guy sold it to me at blue book (when all other high-mpg small cars are rapidly increasing in value)...

Carl
The blue hose should get pressure when the N75 is being used, which is when the ecu is trying to cut boost. Not getting any pressure there indicates to me that the N75 is likely your problem. I'd replace all of these hoses, since they are 10 years old and really don't own you anything else, and if that doesn't do the job, replace the N75. I assume you don't have a VagCom, since I believe you can "cycle" the N75 and do some testing with it.
 

rcoker

Well-known member
Joined
Jul 6, 2008
Location
Tunkhannock, PA
TDI
2002 Jetta ALH
telling what engine I have...

I just aquired a 96 Passat TDI (traded my 66 beetle for it), and need to know if it has an 1Z or and AHU? How do I tell! Any input would be great!:)
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
Almost certainly a 1Z. Most Passats had 1z's with the AHU's coming in on some of the last ones, and some of the A3's.
 

tdijim

Veteran Member
Joined
Jun 4, 2001
Location
Eugene, Oregon
TDI
2000 Jetta TDI, 1996 Passat TDI
Help, please, if you can. Are in-dash electrical burning smells, sizzling sounds, dome, sun roof, rear-defogger shorting out problems covered anywhere? After this happened, the car sizzled when the key was turned and then wouldn't turn over. I'm guessing the infamous pure copper VW wiring on my B4 is producing a direct short inside my dash. Any advice?
 
Joined
Dec 13, 2009
Location
Prince George British Columbia
TDI
1998 Jetta TDI 5spd Sedan 2001 Jetta Sedan / 2003 Jetta Sedan / 2006 Jetta BRM/ 2006 Jetta BRM/ 2014 Passat/
How do I determine which TDI engine I have?

Naive question, I know, but all the same, I'd like to know how to find out which series of 1.9 I have. Vehicle is a 1998 Jetta TDI 5 spd Sedan. Kirk:confused:
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
A 98 Jetta should be the A3 body style, and probably AHU engine, although with this age car, it could be a 1Z. Precious little difference in the engines.
 

slam

Veteran Member
Joined
Jan 30, 2008
Location
San Jose, California
TDI
1996 Passat TDI B4V Wagon
The only big difference I am seeing between the 1Z and AHU motors is in some of the injector pump parts. =)

Hey rdkern, I finally got my ebay vagcom cable! I went to pull my injector pump (yes, finally!) and realized I will also need the cam lock tool and probably a belt tensioner. Ah, the VW learning curve. =)
 
Last edited:

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
Aren't there also slightly different valve stems? could be misremembering there.
 

Gawd129

Well-known member
Joined
Mar 1, 2006
Location
Bellingham Washington
TDI
96 1.6L Diesel Jetta Trek
I have an issue with my '96 MKIII that seems like someone must have dealt with it before, but I'm not sure whether to classify it "Frequent", but I thought it entertaining/annoying enough to ask.

I'm having some kind of electronics issue. All at once, my power locks, sunroof, and fan don't work, and the radio turns off and on every time a hit a bump or pull on the E-brake just enough for the car to register it. The instigator of this was that my power lock button fell off, and before i was able to put it back on, i believe i pressed both the "Lock" and "Unlock" buttons at the same time, effectively frying something, but i've checked the fuses and replaced a couple just to try buy they appear fine.

I think this combination of problems points to one specific thing, but I'm yet to find out what it is. Anyone seen this before?

ThankS!
 
Last edited:

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
Is this a tdi? I didn't think they were offered in the US until 97.

I'd start by cleaning all of the grounds. While you're looking around, you might find something else. But cleaning the grounds can't hurt. I'm not sure where they placed them in the A3, but in the B4 big ones are right near the battery and near the windshield washer fluid. Remove the boost hose if you want easy access.
 
Last edited:

Gawd129

Well-known member
Joined
Mar 1, 2006
Location
Bellingham Washington
TDI
96 1.6L Diesel Jetta Trek
Ah, i probably should have mentioned that it's got an A2 1.6 NA swap in it. Thanks for the advice, i'll go attack the grounds right now.
 

slam

Veteran Member
Joined
Jan 30, 2008
Location
San Jose, California
TDI
1996 Passat TDI B4V Wagon
How can you tell if you're a 1Z or AAZ? Rock auto has two different lines of parts for each????
Generally speaking if it's a '96 it's a 1Z, and '98 and up it's an AHU. '97 was a bit of a mix if I recall correctly. AAZs only came in much later models if I recall correctly.

"The 1996 1Z has no water jacketed heat exchanger on the EGR, a "T" in the fuel line returning from the fuel pump to the fuel filter thermal valve, a "fuel injector for catalyst" solenoid pump attached to the rear side of the air filter box, and a 1Z on the build sticker. The AHU has a water cooler, no T, no 5th injector pump, and a 1Z on the build sticker."

http://forums.tdiclub.com/showthread.php?t=208197&page=3
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
AAZ was in the TD's in Canada prior to the 1Z. If it's an NA, it's not 1Z. Might be something pre-AAZ for all I know, since I though the AAZ was 1.9.
 
Top