ALH turbo solenoid valve?

R26D

Member
Joined
Jun 20, 2023
Location
London Ontario
TDI
ALH
Hey guys, I was going to do an egr delete and every vid and pic I see of this engine looks different from mine. To the right of the EGR i have this little plastic module zip tied to the piping. It has a wire coming out of it aswell as 2 hoses. Looked it up as it says “MT2” on it which is a turbo solenoid valve. Have no clue what it is and why my car has it but not others I see. It does have a rebuilt turbo by the previous owner. any help would be appreciated.
 

dieseldonato

Veteran Member
Joined
Mar 10, 2023
Location
Us
TDI
2001 jetta
That one controls the flap in the intake for the egr. If your deleted and tuned for the delete, you should be able to take it off with no I'll effect.
 

J_dude

Veteran Member
Joined
Jan 9, 2020
Location
SK Canada
TDI
2003 1.9l “Jedi”
Yes @R26D I just checked my car to make sure. That is for the ASV, normally that valve is clipped to the underside of the intake manifold, so it would be just out of sight on most pictures you’ve seen of these engines. Has nothing to do with the EGR actually, it just closes a little butterfly valve in the intake pipe for a few minutes when you turn the engine off. The ASV could be deleted without consequence, but some people like to keep it as extra insurance in case of a runaway.
 

R26D

Member
Joined
Jun 20, 2023
Location
London Ontario
TDI
ALH
Yes @R26D I just checked my car to make sure. That is for the ASV, normally that valve is clipped to the underside of the intake manifold, so it would be just out of sight on most pictures you’ve seen of these engines. Has nothing to do with the EGR actually, it just closes a little butterfly valve in the intake pipe for a few minutes when you turn the engine off. The ASV could be deleted without consequence, but some people like to keep it as extra insurance in case of a runaway.
Thank you so much, also what do you mean by runaway?
 

J_dude

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Location
SK Canada
TDI
2003 1.9l “Jedi”
Sometimes if the turbo fails on these diesels they can start puking oil into the intake piping, and the engine will be running on/burning the engine oil. If this happens the engine will rev way too high possibly wrecking the engine if you don’t stop it in time. And turning the key off won’t stop the engine, as it will keep burning the oil instead of diesel, and the only ways to shut it off are:
A. Stall it out in gear (manual transmission only)
B. Starve the engine of all air, which is technically what the ASV would do.
 

dieseldonato

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Us
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2001 jetta
A Diesel can run away from the fuel rack sticking as well as turbo failure/running on its own oil. The detroits shown in that video I'll nearly guarantee the racks stuck. Was a common failure if they weren't adjusted right or had a lot of wear.
Any runaway can be stopped, and should be. Cut the air supply off. A new turbo and popping the head off and rods out is cheaper then looking for a new block.
 

thecorpgal

New member
Joined
Aug 25, 2020
Location
Seven Bays, WA
TDI
2000 Jetta TDI ALH Manual
Since this is a current thread maybe someone can help me. My early alh has a egr delete with race pipe installed and tuned for the delete. Can I add the asv back on? I have a spare alh for parts and it still has the solenoid for the asv but I don't have the egr solenoid. Is this possible? Or is this pointless?
 

454k30

Veteran Member
Joined
Feb 20, 2006
Location
Long Beach, CA
TDI
2002 Jetta
My early alh has a egr delete with race pipe installed and tuned for the delete. Can I add the asv back on?
The race pipe takes the place of the EGR/ASV housing. I have seen a person make their own ASV inside of a race pipe, but the thing had terrible boost leaks and the experiment was abandoned. Is there a way? yes? Does it use stock parts? Only the actuator and valve. Is it worth it? Not really.
 

R26D

Member
Joined
Jun 20, 2023
Location
London Ontario
TDI
ALH
A Diesel can run away from the fuel rack sticking as well as turbo failure/running on its own oil. The detroits shown in that video I'll nearly guarantee the racks stuck. Was a common failure if they weren't adjusted right or had a lot of wear.
Any runaway can be stopped, and should be. Cut the air supply off. A new turbo and popping the head off and rods out is cheaper then looking for a new block.
I did notice the other day oil leaking from my turbo under the car. But my valve cover looks like it had a previous leak but I’ve cleaned it and haven’t had anything come out the front so I assumed it was oil from the back of the valve cover leaking onto the turbo. But the last owner did say the turbo was rebuilt so I might take it to my local vw show to get them to check it out to be safe to again runaway. Thanks for the help guys
 

dieseldonato

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Us
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2001 jetta
Runaways are a rare occurrence, and are usually from abuse or neglect. Usually you can catch it and get it shut off. Easier if your running a manual transmission just stall it, but a few times I've stuffed rags,or a jacket blocked off the turbo or intake with a board etc. The stupid little block off that are built into intakes all pretty much suck. They leak, or get stuck from never being used.
 

J_dude

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Jan 9, 2020
Location
SK Canada
TDI
2003 1.9l “Jedi”
A Diesel can run away from the fuel rack sticking as well
Right but that’s not something that can happen to these cars.
The race pipe takes the place of the EGR/ASV housing. I have seen a person make their own ASV inside of a race pipe, but the thing had terrible boost leaks and the experiment was abandoned. Is there a way? yes? Does it use stock parts? Only the actuator and valve. Is it worth it? Not really.
Can make a “stealth” race pipe by gutting the EGR valve and keeping the ASV, there’s a thread here on how to do that.
Edit: Found it. Of course pics are NLA, but there are other threads with pics if you search “Stealth Race Pipe” in thread titles.
Runaways are a rare occurrence, and are usually from abuse or neglect. Usually you can catch it and get it shut off. Easier if your running a manual transmission just stall it, but a few times I've stuffed rags,or a jacket blocked off the turbo or intake with a board etc. The stupid little block off that are built into intakes all pretty much suck. They leak, or get stuck from never being used.
Rags usually end up getting sucked in though... 😆
I think if everything is working properly the ASV gets used every time you shut the car off so it shouldn’t stick when you need it. No idea if it actually is useful for stopping a runaway, but that’s the general idea lol.
And yes they are rare, just something to be aware of.
 

Genesis

Top Post Dawg
Joined
Feb 26, 2003
Location
Sevier County TN
TDI
'03 Jetta Wagon
The ASV DOES stick closed once in a while and when it does it of course produces a no-start. 10 second fix too, if you know where it is......
 

dieseldonato

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Mar 10, 2023
Location
Us
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2001 jetta
Right but that’s not something that can happen to these cars.

Can make a “stealth” race pipe by gutting the EGR valve and keeping the ASV, there’s a thread here on how to do that.
Edit: Found it. Of course pics are NLA, but there are other threads with pics if you search “Stealth Race Pipe” in thread titles.

Rags usually end up getting sucked in though... 😆
I think if everything is working properly the ASV gets used every time you shut the car off so it shouldn’t stick when you need it. No idea if it actually is useful for stopping a runaway, but that’s the general idea lol.
And yes they are rare, just something to be aware of.
First, the fuel rack can get stuck on these cars, it's a simple slip ring over the plunger, controlled electronically, Basically the same set up as the manual version. It is a rare occursce for any rotary pump though.
Second, I've stopped a number of runaways with rags, my jacket once and a few time slapping a board over the turbo, and quite a few times cutting fuel lines when fuel rack stuck on Detroits 2 strokes, and a (just 1) cat 3208 with the sleve metering injection pump. (Was in a Massey Ferguson articulated farm tractor.) Truthfully they arnt hard to shut down. Any damage cause from a few rags getting sucked in is a secondary issue to just letting an engine sit there wide open till it blows up. These little engines we're dealing with in our cars arnt hard at all to shut off by choking them out.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Well, there have been numerous reports of run-aways while out on and about on the road (not time for rags, coats, two by fours). Based on the stories, it happens quickly and in some instances, turning-off the ignition doesn't stop the run-away which is likely being fed by the accumulated oil in the Inter Cooler. There are lots of Threads/Posts on the topic. I've always thought the run-away started with a malfunction in the IP as someone mentioned. There are recommended ways to "blow-out" the accumulated oil in the Inter Cooler.

I modified the EGR assembly on the '02 ALH engine I installed in an 84 Vanagon to keep the ASV functional.

The oil leak at the EGR is due to the Valve Guide and Seal wearing out. The oil mist is in the compressed air stream. It is not serviceable. To get rid of the leak, either do the Race Pipe (which I do not care for) or replace the EGR assembly with a new one.

Below are photos of the mod I did to the EGR assembly. (some are not focused very well)











In the pic below, you can see where I tapped the EGR "Valve" hole to access boost for my Boost Gauge.

 

dieseldonato

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Us
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2001 jetta
Well, if you've ragged one and saved the engine, I think it is the first one of read about... been on here over 20 years.
Been working on heavy duty diesels daily for that long, it's not a new concept by any means. You have 2 ways to shut it down, remove fuel or remove air. Can't remove fuel remove the air. It's literally as simple as that. When your talking about an engine that cost $40k to rebuild and a block is $20k it's pretty simple math to give up a $2k turbo and a jacket to shut it it down. 3 rags would kill one if these little engines in a heartbeat
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Been working on heavy duty diesels daily for that long, it's not a new concept by any means. You have 2 ways to shut it down, remove fuel or remove air. Can't remove fuel remove the air. It's literally as simple as that. When your talking about an engine that cost $40k to rebuild and a block is $20k it's pretty simple math to give up a $2k turbo and a jacket to shut it it down. 3 rags would kill one if these little engines in a heartbeat
I think we are discussing a VW ALH engine. Have you had one to run-away out on the road? If so, were you able to grab your rags (that you obviously carry) pop the hood release, raise the hood, remove the clamped hose to the Air Filter Box and stuff those rags in before the engine Hydro Locked on Oil, threw a rod, etc. I've never had that experience as I have always maintained my TDIs very well.

I 100% understand the concept and principle of choking down a Diesel Engine by shutting-off the air (and/or the fuel). I've been owning and driving VW diesels for over 43 years... read and seen about anything possible that could go crazy unexpectedly with these engines. The general consensus is that the engine run-a-ways involve oil from the Inter Cooler and/or a catastrophic failure of the Turbo. So, turning-off the ignition doesn't stop the run-a-way. Some have choked the engine down with the brakes while in gear on the manual transmission and not always with good outcome. As I said, this topic has been discussed for years and years in this forum.

Well, I thought I'd contribute with the mods I did to the EGR.
 

dieseldonato

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Us
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2001 jetta
I think we are discussing a VW ALH engine. Have you had one to run-away out on the road? If so, were you able to grab your rags (that you obviously carry) pop the hood release, raise the hood, remove the clamped hose to the Air Filter Box and stuff those rags in before the engine Hydro Locked on Oil, threw a rod, etc. I've never had that experience as I have always maintained my TDIs very well.

I 100% understand the concept and principle of choking down a Diesel Engine by shutting-off the air (and/or the fuel). I've been owning and driving VW diesels for over 43 years... read and seen about anything possible that could go crazy unexpectedly with these engines. The general consensus is that the engine run-a-ways involve oil from the Inter Cooler and/or a catastrophic failure of the Turbo. So, turning-off the ignition doesn't stop the run-a-way. Some have choked the engine down with the brakes while in gear on the manual transmission and not always with good outcome. As I said, this topic has been discussed for years and years in this forum.

Well, I thought I'd contribute with the mods I did to the EGR.
We are, and no, I have not had to with my car, but I have had to in equipment, many times. If or when it happens ill happily report back to you how it worked out.
Your mods are great and may work, but a simple search on this site lists many people that have run away conditions with stock engines and emissions systems intact that shut the ignition off and still didn't shut the engine down, thus leaving the stall it in high gear and use the brakes, run for dear life or what? Suff the shirt off your back down the intake tube, it takes 20 seconds to rip out of the way. What have you to loose? You shirt, a few rags? It's a 1.9L engine, I've killed 3412 cat engine with a jacket, and lucky it was a single turbo d10 application and the airfikter was easy to get out. Claiming doing the same thing to a much smaller engine won't work is narrow minded at best. After all sharing information and different ways to do things is what forums are supposedly about, I often reminded here that any experience outside of the little diesel engines in the automotive world isn't welcome.
Have a pleasant evening.
 

Marc Bourget

Well-known member
Joined
Jan 17, 2021
Location
Stockton, CA
TDI
2003 Jetta
Any way to clean pooled oil in the intercooler other than removal, cleaning and replacement?

Like placement of a drain valve?
 

csstevej

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Joined
Aug 12, 2004
Location
north nj
TDI
2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,glutton for punishment got another tdi 2001NB,another yellow tdi NB , added an 06 NB DSG
I usually shove a couple of rags in there to soak up any oil, wait a few minutes then pull them out , repeat till no more oil comes out…..
 

Marc Bourget

Well-known member
Joined
Jan 17, 2021
Location
Stockton, CA
TDI
2003 Jetta
What's your interval? With oil changes, or?

Does this pooled oil contribute to coking the intake?

And, is this pooled diesel or oil from the Turbo or valve stems?
 

csstevej

Top Post Dawg
Joined
Aug 12, 2004
Location
north nj
TDI
2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,glutton for punishment got another tdi 2001NB,another yellow tdi NB , added an 06 NB DSG
Usually when I pick up a new car I’ll do that .
It comes from the turbo as the seals are air seals , if you baby the car IE don’t red line it occasionally the oil that leaks past the seals won’t get carried to the cylinders it collects at the low point in the boost tract. Then when you do actually romp on the pedal and you have that huge increase in air flow it picks up the oil and now delivers unmetered fuel to the cylinders and the engine starts running away, and yes you oil become fuel now.
That’s why it’s recommended to “ drive it like you stole it “ with occasional red lines to keep the tract clear of oil commonly called an Italian tuneup.
Also when the turbo starts to wear , excessive oil leaks past the seals and usually starts smoking and oil consumption goes up.
Some people do put a hole in the bottom of the intercooler with a screw that they remove to drain it.
Since I’ve been doing “ Italian tune ups I’ve not needed to pull the lower boost pipe off and use rags to soak up any oil there.
 

dieseldonato

Veteran Member
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Mar 10, 2023
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Us
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2001 jetta
90% of the oil seen in the intake track is from the crankcase vent, not the turbo. Seems to be a popular mod to drill a little hole in the corner of the intercooler as a drain and plug it up with a screw or the likes.
 

Marc Bourget

Well-known member
Joined
Jan 17, 2021
Location
Stockton, CA
TDI
2003 Jetta
I need to go look at what you describe. In the meantime, what about a catch can with a drain to limit the amount introduced to the intake tract?
 

dieseldonato

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Mar 10, 2023
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Us
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2001 jetta
There have been several threads I've read about catch cans etc. A search will yield a few good ones. I just vent it to atmosphere like most my other diesels are. It's not like on a gas car that has pcv, it's just a crank case vent. It's more an emissions thing then needed for the function of engine running properly.
 
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