Just purchased 03 alh 335k . Some issues

This is my first post here on these forums.

I recently purchased a 03 jetta 1.9 tdi with the alh engine.
Was told it has malhone stage 2 tune? And its deleted, but the egr cooler is still in the car? The last owner was lazy and didnt remove it so thats on my list.

When i got it it was lowered, and since i live in new york and snow/pot holes are a thing. I got stock suspension and new e-break cables so i can idle it im the driveway in the morning . I noticed it was hard to start so i swapped out the glow plugs . Still starts a bit rough and i keep blowing a 50a metal fuse above the battery. (Pic included) im not sure if thats the fuse for the glowplugs though .

I did an oil change and the glow plugs and now the boost is no longer staying at 18 psi like it did when i first got the car ... now it likes to sit at 30psi (about 2 bar) is this bad? Or is the turbo just spinning better now that it has clean oil? It has went i to limp mode when accelerating in 4th gear. But didnt throw any codes. I have a vagcom and vcds.

I have a video of the boost and a few pics... i found some cut wires in a harness thats next to the glow plug harness does anyone know what these could be? Or have a good wiring diagram?

Thanks in advance!

http://imgur.com/gallery/N982OpV

https://youtu.be/egKx40sJXnk

Welcome to TDI Club!!
Cut wires could be from a previous GP repair.
Not sure about the boost values, try this handy user contributed search engine-
VW TDI Search Engine
Keep in mind the aluminum oil pan is mere inches from the ground. if you do much high speed urban driving, you're vulnerable to junk on the road.

Fuse arangements in fuse bracket/battery:
S162. Glow plugs (coolant) (50A).
S163. Fuel pump (FP) relay/glow plug relay (50A).
S164. Coolant fan control (FC) control module/coolant fan (40A).
S176. Relays panel interior (110A).
S177. Generator (GEN) (90 Amp.) (110A).
Generator (GEN) (120 Amp.) (150A).
S178. ABS (hydraulic pumps) (30A).
S179. ABS (30A).
S180. Coolant fan

I’m not sure where I got this list but I think it’s somewhat backward and out of order.
S178, 179, 180 are the three green fuses. I really should change that chart I copied it from somewhere here on tdi club but I don’t remember where.

177 is the big one on the left as you’re standing looking at the battery. So that 50amp fuse is your (coolant) glow plugs. Which you can get along without. Or you can check the wiring and see if there is a short.

Has the transmission been swapped from auto to Manual in this vehicle?

Tdijarhead said:

Has the transmission been swapped from auto to Manual in this vehicle?

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Would that fuse even be present on an auto?

bizzle said:

Would that fuse even be present on an auto?

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There are no coolant glow plugs on an auto. I have a friend that bought an 02 Beetle that had been swapped. He popped the hood to let me check it out and the first thing I noticed was a lack of coolant glow plugs.

“Someone swapped the auto transmission for a stick” which concerned my friend at first till I assured him it was a great idea and a good choice by the PO. Apparently the PO just neglected to inform him.

Its the 5 speed, dont think its been swapped,


I raised the car up from fully slammed to stock height (from the amazon) ... parts for these cars are surprisingly cheap

http://imgur.com/gallery/S8cuIBt

I’m not that familiar with tunes but 30psi is a little high, or a lot, depending on what the tune is set up for and if you have a stock turbo or an upgraded one.

Tdijarhead said:

I’m not that familiar with tunes but 30psi is a little high, or a lot, depending on what the tune is set up for and if you have a stock turbo or an upgraded one.

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Im not sure, it looks stock... seems stock... i replaced the vacuum hose from a splitter after the nv75 to the turbo and it still had the stock metal retainer on it ... i couldnt move the actuator tho, i didnt know what wat to move it and i didnt have it on the lift just in the garage on ramps. So i didnt have much room to try and figure it out , i assume its supposed to move down twords the ground / the acuator. I think i may need a new turbo / take mine off and clean the veins ... how long of a job is that? Ive watched a few videos , the car is my daily so i cant go without it mon-fri .

It seems to hold boost well 30psi of it lol ... i just dont want to blow it up and have to scramble. Ive been on the hunt for a used turbo to have as a spare

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30 psi is definitely not normal. My tdi has 312k miles on it now. I've put a lot of work into it, trying to get it to run as perfect as it can. If you have a vacuum pump, hook it up to the vacuum hose that goes to the turbo, from the n75 valve. See if you can get the actuator on the turbo to move at all. If it doesn't move, assuming your vaccum hose isn't leaking, then you turbo actuator is toast or the turbo has build up preventing the vnt mechanism fron working properly. And if you need to take your turbo off to clean/inspect the vnt mechanism. It isnt a particularly difficult job, nor too time consuming. It's also a great time to torch your intake manifold to clean that sucker out.

The stock turbo on these is a vnt 15 and I believe they are good for in the 14-16 lbs of boost. 30 is nearly twice that. Are you sure the boost gauge works properly?

Checking movement of the actuator is best done with a mityvac, crawl back underneath and hook the mityvac up to the actuator, the arm should start to move at 3hg and be fully extended against the stop at 18 or so. Without disconnecting the actuator from the little arm it’s difficult to move it. Once disconnected it should move very easily with just your finger.

There is a circlip that keeps the actuator attached to the little arm. Once removed it is extremely difficult to get it back on, it’s somewhat spring loaded and during reinstallation it likes to pop off and disappear in diverse places. Tying a piece of thread to it during installation keeps it from becoming lost and you from losing your sanity.

If it’s boosting 30 lbs I doubt the vanes are stuck. A mityvac can also be used to check your n75 valve. Disconnect the line to the turbo and plug the mityvac on the nipple. Disconnect the other 2 lines block the ports with your fingers and pump the mityvac up a few lbs. the valve should hold vacuum. If not it needs replacement.

A mityvac is indispensable in diagnosing turbo problems, brake problems and a number of other things. These cars ought to come with a mityvac and a vcds.

Upstate is such a small area, I’m 20min south of Corning just across the PA line.

Tdijarhead said:

A mityvac is indispensable in diagnosing turbo problems, brake problems and a number of other things. These cars ought to come with a mityvac and a vcds.

Upstate is such a small area, I’m 20min south of Corning just across the PA line.

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I'll pick up a mityvac, i live just south of albany. Bought the car from leeds . Had it for 4 months and have been trying to make it last! I try to keep the boost below 25 ... but when passing cars its hard as it spools so quickly!

Its weird that it would limit itself to about 18,spike to 20 then flutter down to about 18 ... then i changed the oil ... well that day i changed the oil, glowplugs, shocks struts and coils / coil overs, wheel hubs and abs sensors. And on the ride home it started staying at 30psi.

The car has the muffler cut out, but still has a cat, and the flex line before the cat is ****ed! I cant idle it in the driveway with out the reserc on because the cabin will smell like diesel! So the next thing i plan to do is get a fake cat since it has no down stream o2 sensors and a new flex line and weld it in...

Anyone know the size of the radiator hose coming for the egr cooler? I want to take that out too ... its already deleted with a race pipe, but the po left the cooler :-/ half ass **** like that drives me nuts!

I have new silicon vacuum hose im going to put on next day that its not raining or below 40ish.

With the egr delete do i need to keep the sensor plugged in to the vacuum lines from the egr valve ? Its plugged in and just dangling and i would like to clean it up a bit.

Also, the wires going to the coolant glowplugs are all cracked ... so that may be why that fuse is blowing . Is there a different fuse for the normal glowplugs? Are they the same glowplugs? I read the glowplug thread and didnt see anything about the coolant ones? Maybee because the autos don't have them? Just trying to learn!

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Coolant glow plugs are different, they aren't monitored by the ECU,

When I do work and get weird results I look into what I did that could cause the symptoms.

The only thing you did that could affect boost are your vacuum lines, assuming your gauge is functioning properly. You could have a bad N75 which is what controls the amount of vacuum going to your turbo actuator. Are you without a doubt sure you ran the vacuum lines to the same ports on the N75?

EDIT: Just went back and noticed you hadn't already messed with vacuum lines...let me go back to the drawing board

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Autos have no coolant glowplugs; the manifold on the end of the block is different and there's no place for them.

30psi is definitely NOT normal nor acceptable with a stock turbo; you will likely blow it up, and fast, if you keep driving it with it boosting that high -- assuming the gauge is right.

There's no harm in leaving the EGR cooler plumbing in place and there's actually an argument for it IF you ever might wind up somewhere with inspections..... plenty of places consider an "inspection" to be a quick visual look and a plug into the OBD port; as long as Readiness bits are set, there's no MIL and it LOOKS stock you pass. Get cute under the hood and you fail even if the light's not on.....

WildChild80 said:

Coolant glow plugs are different, they aren't monitored by the ECU,

When I do work and get weird results I look into what I did that could cause the symptoms.

The only thing you did that could affect boost are your vacuum lines, assuming your gauge is functioning properly. You could have a bad N75 which is what controls the amount of vacuum going to your turbo actuator. Are you without a doubt sure you ran the vacuum lines to the same ports on the N75?

EDIT: Just went back and noticed you hadn't already messed with vacuum lines...let me go back to the drawing board

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I replaced 1 line, after the overboost issue , didnt buy enough to do all of them, so i bought more and plan to do the rest, but it was overboosting before i touched them! I replaced just the line from the turbo to the t before the n75 valve. All the lines look shot! So i plan on replacing them soon!

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When you say 30 psi do you have an actual gauge or are you reading barametric pressure from vagcom. If reading from vagcom you have to minus the actual barametric pressure at your current altitude. Meaning 30 in vagcom could just be 15 psi of boost

In vagcom my car show 33.5 on pressure. -14.9 at my altitude I have so I have 18.6 psi of boost

ktmkris said:

When you say 30 psi do you have an actual gauge or are you reading barametric pressure from vagcom. If reading from vagcom you have to minus the actual barametric pressure at your current altitude. Meaning 30 in vagcom could just be 15 psi of boost

In vagcom my car show 33.5 on pressure. -14.9 at my altitude I have so I have 18.6 psi of boost

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In the video you can see the gauge tipping 30 psi

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It might be worth the time to compare VCDS data against the gauge to ensure it's operating correctly.

It seems to be operating correctly, heres a photo of the graph i took when it first stared happening, the gauge is a mechanical gauge hooked to the egr delete pipe.

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Do i need the other valves (other than the n75 valve) if i dont have a egr? Can i just plug the lines or can i take the valves right out? N239 and n18??? Will i get a cel? Can it be tuned out? Is it already tuned it with malone stage 2 ?

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Where the yellow lines connect at the tees, replace the tee with a straight, and delete all yellow lines and remove n18 and n239, then you'll be good to go.

If you have an ECM tune to delete the EGR, if done correctly you will not get a CEL for uninstalling them.

The stage 2 tune does not come default with the EGR disabled unless you ask for it. I just had a stage 2 done and I left the EGR there.

Nero Morg said:

Where the yellow lines connect at the tees, replace the tee with a straight, and delete all yellow lines and remove n18 and n239, then you'll be good to go.

If you have an ECM tune to delete the EGR, if done correctly you will not get a CEL for uninstalling them.

The stage 2 tune does not come default with the EGR disabled unless you ask for it. I just had a stage 2 done and I left the EGR there.

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What about the dark blue ones?

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My bad, yeah do the same with the dark blue ones.

I redid all the tubes to new silicone 3mm ones today, so we will see if this helps, either way, ill try unplug all the non n75 things! And i have a nee boost gauge on order...

it hit 35psi today, then when going up a hill went in limp mode and only boosted up to 10 psi untill i shut it off and turned it back on ... i try to use the throttle to modulate the boost to keep it below 20ish psi but passing /hills its hard ... it will hold at 30-35 for about 20 secs then go into limp mode ... feels like you hit a wall and you have no power at all!

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If you're hitting those kind of boost pressures with a stage 2, you probably have an issue with your control system. I have a malone stage 2 for a few weeks now and I have yet to push it into limp mode. And I have two big hills I drive up each day, my car Champs up them every time.

Yea ... refer to 1st post, it was fine when i bought it ran 18-20psi .. i did some work ... oil change and glow plugs engine wise and a bunch of suspension stuff , right after that it started boosting higher ... so i went chasing vacuum stuff , next step if this doesnt work is a new n75 , then im gunna have to take the turbo off and clean it (also getting a mity vac to test the actuator

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Yeah I read it earlier, dealing with overboost is a drag. So many things can cause it. Doing the work you did shouldn't have affected the boost. Maybe someone else can chime in so we can get to the bottom of it.

Your next step should be a stock tune and that'll tell you if the mechanical stuff is working right

When you did a boost log did you do requested and actual


EDIT: looked long and hard at the graph and the only thing that seems logical is the N75. It is not requesting that much boost but it's making it and the only way it could do that is a bad N75?

You can swap your N18 with the N75 and see if it calms the boost down
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WildChild80 said:

Your next step should be a stock tune and that'll tell you if the mechanical stuff is working right

When you did a boost log did you do requested and actual


EDIT: looked long and hard at the graph and the only thing that seems logical is the N75. It is not requesting that much boost but it's making it and the only way it could do that is a bad N75?

You can swap your N18 with the N75 and see if it calms the boost down
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Sure can! Maybee not tomorrow morning, as its going to snow pretty bad ,but maybee tomorrow afternoon when i leave work. Are the n75 and n18 the same valve? Just in a different place.

I bought the car with the tune and have no clue how to untune it .. nor do i have a stock tune ... i have a Chinese vagcom cable and vcds lite .

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You can't change the tune with VCDS, you'd have to take it to a tuner to have it done.

The N75 has a larger diameter orifice so the vacuum responds faster than the N18. I used one for about six months before I finally ponied up and bought a new N75. Really didn't notice any difference, but I was also on a stock tune at that time.

Possibly eBay ECU as long as the immo has been disabled but usually tuned TDIs have a 3 bar map sensor and you'll need a 2 bar to go back to stock...I have a stock and a tuned Jetta and the tuned one is so much more fun

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