2001 VW Jetta Auto - Low Mileage Problems

liloldbie

Veteran Member
Joined
Dec 20, 2012
Location
Buffalo, NY
TDI
2001 Jetta GLS TDi
I recently picked up a 2001 Jetta with the dreaded O1M with 212,800 and counting. As with every failing transmission it does have a slight surging issue at speed and the torque converter slip between gears. It is manageable in my short commutes to where it is a non-issue. On my commute home from Maine I achieved almost 500 miles on my tank before the fuel light came home netting around 41 mpg traveling at an average speed of 73 mph.

Fast forward a tank or two to now. I am likely to see less than 400 miles on this tank. Temperatures are in the low single digits and my commute is roughly 8-15 miles one way so the car barely has time to warm up. I'm sure it also doesn't help that I am constantly going up or down hills and all back roads with stop signs.

Known issues:
Slipping O1M
Low Temps (single digits)
Does not reach 190* (faulty sensor? tstat?)
16" Blizzaks @ 37 psi
Faulty Wastegate Actuator

I do occasionally see an over boost code when traveling up hills. I just have to cycle the ignition and all power is back. I don't believe I am down on power other than when I hit limp mode.

Plans:
5-speed swap coming (thanks jbleu)
New coolant temp sensor
New thermostat
New wastegate actuator

Wondering if what I have planned here can regain my lost mileage? Am I stuck with sub par mileage due to weather and commute? I was thinking that swapping in a set of Bosio 520's and a tune could help my mileage after I fix my overboost problem up hills. If an actuator doesn't fix my issue I was thinking VNT-17 and a tune to compliment. Let me know what you guys think.

I do have vag com so I am able to check various things such as IQ, Injection timing, etc etc. Not really sure where to start I guess.
 
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MikeMars

Veteran Member
Joined
Mar 6, 2008
Location
UK
TDI
Vento 1.9 TDi (retired), A4 1.9 TDi (rear end collision), VW Passat 1.9 TDi (retired), Audi A2 1.4 TDi
The manual box should help your MPG significantly, and the thermostat/temp sender should help the engine to heat up properly. Dunno about the wastegate actuator.

I would suggest leaving it at that for the time being ... if you try to change too many different things simultaneously it all gets confusing since you don't know which the effect of each individual change.
 
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dieseldorf

Top Post Dawg
Joined
Oct 11, 2000
Location
MA
TDI
ex- 1996 wagon, ex-2000 Jetta
I recently picked up a 2001 Jetta with the dreaded O1M with 212,800 and counting.

You should consider yourself extremely fortunate. That's Guiness Book territory.

I'd be focusing on my savings account and building that up for the manual gearbox swap, as already suggested.

Plans:
5-speed swap coming (thanks jbleu)
New coolant temp sensor
New thermostat
New wastegate actuator
set of Bosio 520's
a tune could help my mileage
I can never comprehend doing mods on a car with myriad problems. Get the e-z things fixed. If the actuator (rotted out??) is a known problem, fix it ;) Try to fix one item each weekend 'til you've got rid of the problems you outline. See what new ones pop up. I'd be making a broad assessment of the car's general condition (rust) and trying to arrive at a decision if it's a keeper or otherwise.

Warm weather or a move to FL is going to fix your perceived mileage problem...it's not unique to your vehicle. Fuel economy plummets, whether gas or diesel, during these extreme cold temps, Lilo. I would not automatically jump to the conclusion that something is wrong. I think my fuel economy is off by about 40% this past week. Oil temp has been so low, not even approaching "warmed up" by the time I arrive at my office. It is what it is, right?

Lilo, welcome aboard, and let us know how else we can be of resistance !!
 

aja8888

Top Post Dawg
Joined
Dec 25, 2007
Location
Texas..RETIRED 12/31/17
TDI
Out of TDI's
You should consider yourself extremely fortunate. That's Guiness Book territory.
We've got one in the family with well over 200,000 miles on it and still shifting quite nicely. It's been maintained throughout its life and there is no reason to believe that the lowly 01M can't last as long as the other auto boxes in these TDI's.

Our TWO 2005 Passat TDI's with the ZF autos in them both were needing rebuilt transmissions ($4K each installed) before 150,000 miles of careful and well maintained miles. Read the B5 threads to see a history of early, and colossal failure of those hefty transmissions and torque converters.
 

fruitcakesa

Top Post Dawg
Joined
Feb 18, 2007
Location
Vermont
TDI
04 jetta 5 spd wagon
I recently picked up a 2001 Jetta with the dreaded O1M with 212,800 and counting. As with every failing transmission it does have a slight surging issue at speed and the torque converter slip between gears. It is manageable in my short commutes to where it is a non-issue. On my commute home from Maine I achieved almost 500 miles on my tank before the fuel light came home netting around 41 mpg traveling at an average speed of 73 mph.

Fast forward a tank or two to now. I am likely to see less than 400 miles on this tank. Temperatures are in the low single digits and my commute is roughly 8-15 miles one way so the car barely has time to warm up. I'm sure it also doesn't help that I am constantly going up or down hills and all back roads with stop signs.

Known issues:
Slipping O1M
Low Temps (single digits)
Does not reach 190* (faulty sensor? tstat?)
16" Blizzaks @ 37 psi
Faulty Wastegate Actuator

I do occasionally see an over boost code when traveling up hills. I just have to cycle the ignition and all power is back. I don't believe I am down on power other than when I hit limp mode.

Plans:
5-speed swap coming (thanks jbleu)
New coolant temp sensor
New thermostat
New wastegate actuator

Wondering if what I have planned here can regain my lost mileage? Am I stuck with sub par mileage due to weather and commute? I was thinking that swapping in a set of Bosio 520's and a tune could help my mileage after I fix my overboost problem up hills. If an actuator doesn't fix my issue I was thinking VNT-17 and a tune to compliment. Let me know what you guys think.

I do have vag com so I am able to check various things such as IQ, Injection timing, etc etc. Not really sure where to start I guess.
This seems like a major reason for the poor FE.
Not much you can do to change it.
 

PeterV

TDIClub Enthusiast, HO5G Doyen & Zen Master
Joined
Aug 17, 2000
Location
So, NH.
TDI
2000 Jetta 5 sp.
A Vag Com scan of your car might yield a code that can be rectified. The Tranny is your real problem and winter fuel is not helping.

A tune will help and some nozzles. You have an 11 mm pump which is good.

A chat with our trusted TDIclub vendors will be in your best interest. A big turbo at this point will not help much. I will say this as others won't you bought the wrong car. You can fix this by doing the 5 speed and while you are at is do the 5 th gear swap.

The costs are high for you but you will have a pretty god car after a lot or work.
 

liloldbie

Veteran Member
Joined
Dec 20, 2012
Location
Buffalo, NY
TDI
2001 Jetta GLS TDi
A Vag Com scan of your car might yield a code that can be rectified. The Tranny is your real problem and winter fuel is not helping.

A tune will help and some nozzles. You have an 11 mm pump which is good.

A chat with our trusted TDIclub vendors will be in your best interest. A big turbo at this point will not help much. I will say this as others won't you bought the wrong car. You can fix this by doing the 5 speed and while you are at is do the 5 th gear swap.

The costs are high for you but you will have a pretty god car after a lot or work.
Luckily I bought this car with the known transmission problem at a very good price which leaves me room for mods, such as the 5 speed swap. Even after I do the swap I still have enough equity in the car to make necessary replacements to avoid losing any money if I needed a quick sale. This is a main reason why I am trying to fix any and all issues I have on this car so I can regain my mileage and a reliable car. I don't need it to be fast, I have the S4 for that.

I should have the swap this coming weekend. At that time while the motor is out I will replace the turbo actuator, all vacuum lines, coolant temp sensor, and thermostat. Hopefully with all that work done I can report back with a superior tank.

I am definitely interested in a tune and nozzles. Even after doing those mods I will have equity left in the car. More information on that would be great. I've heard great things about RocketChip and Malone.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
I recently picked up a 2001 Jetta with the dreaded O1M with 212,800 and counting. As with every failing transmission it does have a slight surging issue at speed and the torque converter slip between gears. It is manageable in my short commutes to where it is a non-issue. On my commute home from Maine I achieved almost 500 miles on my tank before the fuel light came home netting around 41 mpg traveling at an average speed of 73 mph.

Fast forward a tank or two to now. I am likely to see less than 400 miles on this tank. Temperatures are in the low single digits and my commute is roughly 8-15 miles one way so the car barely has time to warm up. I'm sure it also doesn't help that I am constantly going up or down hills and all back roads with stop signs.

Known issues:
Slipping O1M
Low Temps (single digits)
Does not reach 190* (faulty sensor? tstat?)
16" Blizzaks @ 37 psi
Faulty Wastegate Actuator

I do occasionally see an over boost code when traveling up hills. I just have to cycle the ignition and all power is back. I don't believe I am down on power other than when I hit limp mode.

Plans:
5-speed swap coming (thanks jbleu)
New coolant temp sensor
New thermostat
New wastegate actuator

Wondering if what I have planned here can regain my lost mileage? Am I stuck with sub par mileage due to weather and commute? I was thinking that swapping in a set of Bosio 520's and a tune could help my mileage after I fix my overboost problem up hills. If an actuator doesn't fix my issue I was thinking VNT-17 and a tune to compliment. Let me know what you guys think.

I do have vag com so I am able to check various things such as IQ, Injection timing, etc etc. Not really sure where to start I guess.

The transmission swap alone is worth 10 MPG depending on how you drive it. The other things your mentioned obviously need do too, so that is a good place to start. Question, how long since the timing belt was done? Intercooler drained?
 

liloldbie

Veteran Member
Joined
Dec 20, 2012
Location
Buffalo, NY
TDI
2001 Jetta GLS TDi
The timing belt was done at 188,xxx with a 60k belt. There's a service sticker on the battery box that says service again at 238,xxx. I have no idea when the last time the intercooler was drained. I am thinking I should add that to my list while the motor is out?
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
The timing belt was done at 188,xxx with a 60k belt. There's a service sticker on the battery box that says service again at 238,xxx. I have no idea when the last time the intercooler was drained. I am thinking I should add that to my list while the motor is out?
There are a few things in the ALH powered TDI community that can ruin your TDI day! :) We will see if we can enlighten you now so you don't have a heartbreak later ;)


Motor doesn't have to be out to drain the inter-cooler. It's as simple as removing the rubber coupling in the lower passenger side fender well to the lower part of the inter-cooler and letting the oil drain out. Definitely use some container or oil drip pan to catch the oil-it can be really messy. Some clean rags or paper towels can be used to sop any oil that is still left in the lower inter-cooler cavity. Get all the built up liquid oil out that you can! If the oil is allowed to build up in that location under high boost when aggressively accelerating the oil can be ingested into the intake and a run away condition can occur. This is where the motor essentially self destructs and uses it's own engine oil for fuel until it has no oil and cooks itself to death. Hydrolock/bent rods and other nasty things can happen too.

Also, as far as the timing belt goes that is one area that if not done properly and with very high quality replacement parts can toast and engine quickly. Our trusted vendors are selling the upgraded timing belt kits that allow 100K mile intervals for them now. If your not 100% sure that a TDI guru/TDI specific trusted mechanic replaced the TB and all related components with top notch quality parts then save yourself a headache and do it while you have the engine out. Plus even with that 60K timing belt your not too far off from needing it anyhow. Here is one TB kit from a TDI club trusted vendor that has all parts that you will need for the complete job:

http://www.metalmanparts.com/product.sc?productId=1


Also, why are you removing the engine? The tranny swap doesn't require it to be removed. Then again if you are doing a TB job it's a whole lot easier with it out!
 
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liloldbie

Veteran Member
Joined
Dec 20, 2012
Location
Buffalo, NY
TDI
2001 Jetta GLS TDi
There are a few things in the ALH powered TDI community that can ruin your TDI day! :) We will see if we can enlighten you now so you don't have a heartbreak later ;)


Motor doesn't have to be out to drain the inter-cooler. It's as simple as removing the rubber coupling in the lower passenger side fender well to the lower part of the inter-cooler and letting the oil drain out. Definitely use some container or oil drip pan to catch the oil-it can be really messy. Some clean rags or paper towels can be used to sop any oil that is still left in the lower inter-cooler cavity. Get all the built up liquid oil out that you can! If the oil is allowed to build up in that location under high boost when aggressively accelerating the oil can be ingested into the intake and a run away condition can occur. This is where the motor essentially self destructs and uses it's own engine oil for fuel until it has no oil and cooks itself to death. Hydrolock/bent rods and other nasty things can happen too.

Also, as far as the timing belt goes that is one area that if not done properly and with very high quality replacement parts can toast and engine quickly. Our trusted vendors are selling the upgraded timing belt kits that allow 100K mile intervals for them now. If your not 100% sure that a TDI guru/TDI specific trusted mechanic replaced the TB and all related components with top notch quality parts then save yourself a headache and do it while you have the engine out. Plus even with that 60K timing belt your not too far off from needing it anyhow. Here is one TB kit from a TDI club trusted vendor that has all parts that you will need for the complete job:

http://www.metalmanparts.com/product.sc?productId=1


Also, why are you removing the engine? The tranny swap doesn't require it to be removed. Then again if you are doing a TB job it's a whole lot easier with it out!
I'm pulling the motor to take care of the transmission swap to make it easier. I don't like working in tight places. I'd rather spend the extra two hours pulling it and putting it back in than cussing and swearing while working in tight places.

I figure I am not going to start taking things apart until I have the car down for a good 2 days. I know you don't have to remove the engine to R&R the intercooler. I've just been putting around, no aggressive driving as I hit boost, so I should be fine until I get a chance to do the swap.

As far as timing belt goes, I will replace it now anyways with a 100k kit. I already have a set of locking tools from my previous TDi so I am good there. I figure it's better safe than sorry when it comes to buying used cars.

Wondering if I should buy a set of lifters and replace those as well while the motor is out? I know I've seen my fair share of threads that have lifters destruction. Think it's worth it?

Frostheater will be ordered as well!
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
I'm pulling the motor to take care of the transmission swap to make it easier. I don't like working in tight places. I'd rather spend the extra two hours pulling it and putting it back in than cussing and swearing while working in tight places.

I figure I am not going to start taking things apart until I have the car down for a good 2 days. I know you don't have to remove the engine to R&R the intercooler. I've just been putting around, no aggressive driving as I hit boost, so I should be fine until I get a chance to do the swap.

As far as timing belt goes, I will replace it now anyways with a 100k kit. I already have a set of locking tools from my previous TDi so I am good there. I figure it's better safe than sorry when it comes to buying used cars.

Wondering if I should buy a set of lifters and replace those as well while the motor is out? I know I've seen my fair share of threads that have lifters destruction. Think it's worth it?

Frostheater will be ordered as well!

Right, not a bad idea to do it with the engine out of the vehicle.

Since you will have the valve cover off during the TB job(to verify correct camshaft positioning) just do an inspection of the cam lobes and the lifters. If it looks good, jut do the complete TB change(idler pullies, water pump etc) and call that a day. Also, while the engine is out go ahead and order a IP pump reseal kit and install some of those parts now and wait to do the others later. I would do the high pressure head O ring and some of the seals that are on the bottom of the IP that are impossible to get to with it installed in the car. I wouldn't do the top seals until you have the tranny swap done and the engine back in the car and running. That way you know you didn't change the quantity adjuster positioning. You can do the upper ID case seals really easy later on after the car is running and all. Don't want to invite too many problems. Also, inspect the crankshaft seals while your at it. Certainly don't want a leaky front or rear main when you get done with it all!
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Almost forgot, when you have the engine out, go ahead and replace the hard coolant pipe seal/O ring. It's a bear to do it with the engine in the car! You will be glad you did :) The seal is really cheap also.
 

liloldbie

Veteran Member
Joined
Dec 20, 2012
Location
Buffalo, NY
TDI
2001 Jetta GLS TDi
Having a hard time finding the IP seal kit. Not really sure where to get it. I will probably replace the lower ones as you said.

I have spare o-rings for that pipe ;) though it was never leaked on me before when removed. I will replace it as this car has higher mileage than the others motors I've pulled. Thanks for the heads up.
 

josh8loop

Veteran Member
Joined
Sep 15, 2009
Location
Vero Beach, Fl.
TDI
2002 VW Jetta TDI Manual(performed 01M to 5-speed swap) - 183,000 miles and climbing!
Having a hard time finding the IP seal kit. Not really sure where to get it. I will probably replace the lower ones as you said.

I have spare o-rings for that pipe ;) though it was never leaked on me before when removed. I will replace it as this car has higher mileage than the others motors I've pulled. Thanks for the heads up.

Here is one kit that is available:

http://www.idparts.com/catalog/product_info.php?products_id=1143



Here is another that uses Viton for the seals:

http://www.dieselgeek.com/TDI_Injection_Pump_Seal_Kit_p/pmp-fullkit.htm
 
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