ALH TDI 1.9l Engine Smoke

Joined
Mar 10, 2020
Location
Maine
TDI
2002 Golf
Good afternoon everyone,

I’ve got a 2002 VW golf tdi 1.9 alh engine code and she’s got a nasty smoke.

when revving engine it smokes out from the engine and the tailpipe. It’s a darker whitish and smells absolutely terrible. Like pure diesel oil. When it happens it blows straight through my air vents and fills the car and right out the tailpipe.

what I’ve done:
I ripped off the intake manifold as it was severely restricted when I pulled off the egr. Didn’t want to clean my manifold so I bought a new one along with a new egr from KermaTDI. All new gaskets and I did all the vacuum lines and n75 and the other one right next to it. Can’t remember it’s name. Also check valve.

I figured the nearly clogged intake was the issue and just did the vacuum lines on the side. I still have the same issue. No matter hot or cold it smokes bad. It hesitates too, more like bucking. When I put it in any gear it just kinda jumps along just like the engine when driving. Almost sounds like a miss but not sure. Any ideas?
Fuel flows good. Filter looks ancient so I have a new one but I don’t wanna keep putting more parts in it if it’s not gonna fix my issue.

I don’t have VCDS so I’m restricted to what I can do. tho I have no codes that I didn’t have before.

Only check engine lights I have are cylinder 1 2 and 4 glow plug and an overboost. I’ve had those forever tho so I’m sure those aren’t the cause.

also checked turbo and vanes are moving when actuated and spins freely so it’s not my turbo. I have a few ideas but I’m not 100% sure. I’m thinking maybe injectors, injector pump

Also not loosing any fluids whatsoever. Coolant is perfect and oil is a little high, I did overfill a bit. Oil smells normal and feels normal so I’m assuming no coolant in the oil especially because I haven’t lost coolant. It smells like diesel oil maybe gas. But I have no bubbles in my lines or anything so I’m really lost. Any replies are greatly appreciated
 

STDOUBT

Veteran Member
Joined
Jul 30, 2007
Location
Portland, effing Oregon
TDI
dos jettas
Smokes out from the engine you say?
You didn't mention checking the downpipe and flex pipe. Are they crack-free?
Assuming your turbo is not original, did the old one ever blow oil out the exhaust
on it's way out?
Timing belt's OK?
Things to ponder while you find a VCDS.
 

Poor King

Veteran Member
Joined
May 20, 2020
Location
NY
TDI
'91 Jetta, '91 GTI, '04 Touareg
My flex pipe/downpipe is shot however my car did not smoke like yours do. Might be easier for you to identify the culprit by putting the car on a lift and starting it. I have an ALH turbo with 50k after rebuild that I can left go. However, I feel like it may be a cracked head or piston ring.
 
Joined
Mar 10, 2020
Location
Maine
TDI
2002 Golf
Hey guys thanks for the tips. I have 174k on my engine and it is the original turbo. It does seem to spoil fine and when I checked the actuator, it’s actuating the veins so I don’t think it’s the turbo but I might be missing something. I’m not losing any oil which is weird.

it’s a weird case. When I give it gas anything above 2rpm starts to hesitate I feel engine like twitch. Like a misfire I’d assume. Wether I’m in gear or in neutral it doesn’t affect it. Tho it makes driving much more difficult because it bucks really really bad, that’s how this all started. On my way home from work I stopped at a light and threw her in neutral. When I put it in firstand accelerated it like hopped it’s way up to speed and continued through all gears until I got home. Luckily was only a block away so I made it home.

smoke comes, to be more exact out from the backside of the engine. When hoods up. And then comes out the tail pipe. Not at the same time, in that sequence. Engine smokes first then exhaust. And that’s only after I left off the gas due to bucking. Also the smoke blows straight through my air vents completely clouding out the car and making it smell badly of diesel. So I’d assume my exhaust wouldn’t be clogged if it’s blowing tons of smoke right? I could check my down pipe tho.

I’d always thought diesel not burnt was black? Maybe not.

the more I read into this I’m having a hard time determining the smell and color of it. People say there’s white blue grey and black. I could have either white blue or grey. I’m not sure it’s just very light colored and smells like diesel. I’m starting to think it could be unturned diesel And I’m hoping I haven’t lost compression. All glow plugs do is keep the block warm correct? They aren’t needed for the combustion?. If I do my glow plugs and harness would it help? Since my engine light is on for 3 out of 4.
 
Joined
Mar 10, 2020
Location
Maine
TDI
2002 Golf
Hey so I just wanted to give an update. Going to purchase a compression test kit and test compression. If it’s not compression I’d assume it’s my turbo? But what are the chances that it was working 100% and I even brought it into VW and had them test the turbo and they said it was good so I really don’t think it’s the turbo. I’m beginning to think either piston rings or bent rod. Which sucks because it’s only got 170k on her. She’s just broken in in my book with tdi’s. Really hope that’s not the case but that’s where I’m at. Before I go to rip off the head I may try a set of refurbed injectors. I already pulled fuel from after the fuel filter and the flow is good so if it is a fuel issue it’s coming after the injection pump. So either IP or Injectors. Is there a way I can test either??
 

Poor King

Veteran Member
Joined
May 20, 2020
Location
NY
TDI
'91 Jetta, '91 GTI, '04 Touareg
I'm curious to know what the culprit is. I have heard of piston rings on tdi's losing whole pieces. Wonder what you'll find if you remove the oil pan. Are you losing coolant?
 

eddieleephd

Top Post Dawg
Joined
May 27, 2012
Location
Battle Ground, Wa
TDI
2002 jetta Wagon
Really need to check the timing, sounds like it jumped. When was the last time belt job done?
Next get VCDS connected and run some logs, only after you've verified the timing is dead on.
 

jokila

Vendor
Joined
Dec 3, 2004
Location
Houston, Texas
TDI
2003 Jetta GLS, Manual
This sounds like a bad compression in a cylinder or leaky injector nozzle. The smell and smoke is unburned fuel. A valve losing its seal can cause such a condition. Rods don't bend by themselves and you didn't say how you came to this situation. Did you have some event like a runaway engine?

Get a compression gauge and check them.
 
Last edited:

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Yes, a compression check will give a general idea of the condition of the internals.
But those symptoms could also be fueling, that's diesel+air. Specifically the air, a break or misfit with one of the large pipes or even air restriction somewhere.
 
Joined
Mar 10, 2020
Location
Maine
TDI
2002 Golf
Figured I’d post an update, turned out the MAF I had bought new was bad from the start. Can’t believe it caused such issues, and still can’t figure out why the problem never went away even when I unplugged it. Even though I wasn’t getting codes for my MAF I replaced it anyway and I guess I got unlucky enough to get a bad one still can’t believe it was the culprit. Thing runs like a top now!
 
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