ALH Runaway. Got it shut down immediately, now no start.

FordManMT

Active member
Joined
Jan 30, 2017
Location
NW Montana
TDI
2000 Jetta MK4 TDI
200 Jetta TDI AHL manual. 200k miles.

I was driving to work, at about 60mph I was accelerating, all of the sudden the engine rpm skyrocketed. Dumping black smoke. Obviously startled me so I immediately shut it off and thankfully it didn’t keep running.

So after a few mins I tried to re-start it. Turned over just fine but wouldn’t fire on any cylinder. No unusal noise.

There is some oil leaking by the turbo, I checked the oil level and it’s still good.

I don’t think the engine was damaged even though the needle was buried for a couple seconds.

IP pump failure? I can’t foresee it being a turbo seal because you would think it would fire again.

Idk gents I’m at a loss.
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
First thing is don't panic.

Not an IP pump failure I bet. It will struggle to start with oil residue in cylinders. Remove glow plugs and crank it over. Look for oil spurting out of cylinders. Maybe put a rag or paper towel over each GP hole to catch and estimate how much comes out. Then re-install plugs. Also drain the IC. They hold 3/4 of a cup. Ask me how I know. My 99.5 had a similar runaway except at parking lot speeds. I did this procedure with a friend's help and all was fine.


Restart but make sure to have it in third gear with your foot on the clutch and the other on the brake and be ready to dump the clutch if it races away from residual oil in system.

After that you can work to determine root cause. Probably a worn/old turbo. Check for free play.
 
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FordManMT

Active member
Joined
Jan 30, 2017
Location
NW Montana
TDI
2000 Jetta MK4 TDI
Not an IP pump failure I bet. It will struggle to start with oil residue in cylinders. Remove glow plugs and crank it over. Look for oil spurting out of cylinders. Maybe put a rag or paper towel over each GP hole to catch and estimate how much comes out. Then re-install plugs. Also drain the IC. They hold 3/4 of a cup. Ask me how I know. My 99.5 had a similar runaway except at parking lot speeds. I did this procedure with a friend's help and all was fine.

First thing is don't panic.


Restart but make sure to have it in third gear with your foot on the clutch and the other on the brake and be ready to dump the clutch if it races away from residual oil in system.

After that you can work to determine root cause. Probably a worn/old turbo. Check for free play.
I won’t be able to get the car off the trailer until tomorrow but as soon as I do I’ll do that thank you.

It’s my daily driver and I’m currently super deep in my ford-cummins conversion then this happens lol.
 

FordManMT

Active member
Joined
Jan 30, 2017
Location
NW Montana
TDI
2000 Jetta MK4 TDI
Got the car off of the trailer. Pulled glow plugs and turned it over for around 1min. There was definitely some oil coming out.

After it was just puffs of fuel I re-installed the glow plugs. Fired the engine up.

It’s defintily not running on one cylinder. Extremely rough idle, pouring white smoke out the exhaust.

So I’m not sure if I’m looking at a failed valve, hole in piston, or blown head gasket...
 
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Vince Waldon

Top Post Dawg
Joined
Apr 25, 2009
Location
Edmonton AB Canada
TDI
2001 ALH Jetta, 2003 ALH Wagon, 2005 BEW Wagon
Compression test and then go from there. :( :)

You're likely going to find low numbers in a couple cylinders (2 and 3 seem to bear the brunt most often) and if you can hear it in how the engine runs now probably *very* low in one of 'em.

A couple tablespoons of liquid oil is all it takes.

My suggestion is to not run it more than you have to... bent rods can and will suddenly break... and then fly thru the block.

And yeah... I've never seen so much black smoke as when I had my runaway. Actually not true: we had an old rotary-engined Mazda RX3 that blew the apex seals... now *that* was a smokescreen. :) :)

Compression test will give you lots of clues as to what to do next.
 
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dieseldrive

Well-known member
Joined
Feb 16, 2013
Location
North Carolina
TDI
2001 Jetta
Extremely unlikely its the pump. The only thing in the VP 37 pump that could cause a runaway would be a seized quantity adjust actuating shaft (I have never seen one seized - have rebuilt hundred of them). Even if that happened, the ignition switch SHOULD shut it down.

The stop solenoid on the VP 37 is actually a secondary shutoff, the primary is the QA actuator.

Check your turbo for pumping oil.
 

FordManMT

Active member
Joined
Jan 30, 2017
Location
NW Montana
TDI
2000 Jetta MK4 TDI
So today we pulled the head, took about 3 hours so not to bad.

Cylinders 3-4 were coated in oil. And visually piston 4 is lower than piston one. So pretty sure it’s a bent rod.

What are the chances I can put to rods and rod bearings in it with a new head gasket?

I would rather go that route than buy a $1000 Engine sight unseen.
 

Genesis

Top Post Dawg
Joined
Feb 26, 2003
Location
Sevier County TN
TDI
'03 Jetta Wagon
Pull the pistons and rods and send them to be matched and balanced. I'd hone the cylinders while you're at it to break the glaze and put new rings on, plus replace the bearings of course.

Assuming everything else looks ok (bore condition, etc) the odds are quite high you're fine going that route.
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
2x on the above ^^^
If the piston skirt is collapsed it will rock more then the others, possibly loosing compression.
The pistons and rods all have to be matched for height, length, and weight (balanced)
 
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