ALH newbie needs help / advice

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
(Cause has been identified, see post 64)
2002 Jetta starts easily, idles smoothly, but revs only to 1800 and lots of smoke. I'm out of ideas looking for advice on next steps.

I bought a well priced 02 Jetta with the thought of making it a replacement for the B5.5. It needed work but I thought it was well within my abilities.
Here's a link to the prior owner's post on the same problems:
http://forums.tdiclub.com/showthread.php?t=340942

The summary of advice from that thread:
Turbo replaced (not by the poster, but allegedly by the owner from whom HE bought the car), tried with MAF disconnected, vacuum lines replaced, vacuum valves checked, confirmed cat not blocked-up, intake piping all connected, timing checked, intake is clear, vacuum hose routing confirmed, vacuum retention (leak test) confirmed, snow screen clear, anti shudder valve functioning correctly.
last advice to that owner was to check the quantity adjuster, the EGR, ECU, and compression. The owner was intending to swap in a known good pump, but the thread ended there and a car for sale thread was started.

So I bought it, and have gone through much of the same.
Heavy smoke?


Note the size of the ash chunks that came out after the car was trailered home.



Maybe the cam and followers are worn such that the valve timing is off, so I pulled the valve cover. YeOW! Sludge city!




I can't see well enough to examine the cam and followers. I drained the sump and this is the viscosity. note the angle of the pan relative to the plywood flat on the ground.


Buttoned it back up and ran a few quarts of sludge thinner through a new filter to clean things. Cam has slight wear showing at the lobe tips and a slight dish of the followers, but nothing I haven't seen before on other engines that run well. The oil flush didn't change the symptoms though.

All four injectors were swapped out for a spare set, no different. VCDS shows the injector balance is +-.5 (+-2.0 is limit)
Down pipe removed (eliminating a blocked cat / exhaust as a cause), no different.
Intake piping removed at anti shudder valve, no boost, but also eliminated the intake /intercooler restriction question, no different.
Pulled the head. Cross hatching is still visible on the walls and only a very slight ridge at the cylinder top. Valve seats look good. New head gasket, bolts, water pump, 100k belt kit, serp tensioner installed, no different. Still starts easily, idles smoothly, but can't exceed 1800 rpm even at no load and copious amounts of grey smoke. Compression is a bit low, but for 250k miles it isn't bad at 330, 345, 345, 330. Timing is just slightly advanced, QA is about 5.
All appears to be normal, so I get permission to use her Golf as a known parts supply.
ECU from her Golf (RC3, EGR delete, immobilizer delete) runs exactly the same in my Jetta as the stock Jetta ECU does, nothing over 1800 rpm is possible. My Jetta ECU runs her engine for a second or two, enough time to get up to 3k+ rpm, before the immobilizer kills operation. Doesn't sound like the ECU.
Swapped in her 11 mm fuel pump, no different.
Swapped in her MAF, no different.

I removed the (allegedly new) turbo as it doesn't spin as freely as I thought it should, possibly from bearing damage due to sludged oil. The vanes look to be in pretty good shape with no play in the bearings, nonetheless I pulled it apart.



Maybe this turbo bearing oil by-pass is the source of the "excess fuel" smoke? A pending run-away? More oil pressure at higher-than-idle rpm pumping more oil into the intake air? Compression causing ignition prior to TDC and holding back the rpm? The turbo needs to be replaced anyway to I blocked off the oil supply for a trial. No different. Same amount of smoke, same limit of 1800 rpm at no load.
VCDS shows no faults.


So I've cleaned and restored full function to the turbo (bearings are still bad and will need to be replaced, but first things first), oil sludge has been cleaned up well enough for now, ECU, injector pump, injectors, MAF have been swapped out with known good substitutes, vacuum hose integrity has been confirmed, solenoid valves operate correctly and properly control vacuum actuators for VNT, EGR and anti-shudder, timing and IQ are within limits. Compression is good enough. The engine starts an idles fine, begins to run raggedly at about 1400 rpm and can't get over 1800~2000 and bellows clouds of smoke.

I'm out of ideas, frustrated, and ready to eat humble pie.
What are your suggestions I try?
 
Last edited:

Seatman

Top Post Dawg
Joined
Apr 23, 2010
Location
Scotland
TDI
2014 Skoda rapid elegance 1.6 cr tdi
Holy crap! That is well and truly sludged! Have you tried it with the intake pipe disconnected from the inlet manifold? Maybe the IC is choked up.
 

Jettascuba

Veteran Member
Joined
May 27, 2009
Location
South Africa
TDI
2002 VW Jetta
1) Make sure your boost path is open - IC specifically, as previous poster said, remove the pipe to the EGR

2) Use VCDS to check your MAP

3) Check your timing

4) How easy is it to turn the engine by hand with the glow plugs removed? Should be easy with one hand.

BTW, how does your turbo oil feed line look like? That turbo bearing getting any oil with all that sludge?
 

dogdots

Vendor
Joined
Sep 4, 2002
Location
Kansas City
TDI
None
Those pictures are disgusting. Whoever owned this before needs a kick in the nuts. I read thru the thread but didn't see where you pulled the intake manifold to see if it was completely blocked. With the sludging inside I would bet the intake is completely blocked. I had a customer drive last week to our shop from Iowa and when I checked his intake it was less than 1" diameter hole in the crud and his engine was spotless inside and car was an 03 ALH wagon with less than 100k.

All that black smoke is unburned fuel, and if it starts choking itself out at that low RPM you got airflow problems not fuel problems I would guess.
 
Last edited:

PeterV

TDIClub Enthusiast, HO5G Doyen & Zen Master
Joined
Aug 17, 2000
Location
So, NH.
TDI
2000 Jetta 5 sp.
The head has been off twice & Lug_Nut drove to the Ho5G for the compression tester.

This particular TDI has something somewhere that is out of spec. The Northeast Group knows that Our Lug_Nut knows these cars there is something weird VERY weird here .
 

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
You removed the head, but if you did not remove the intake from the head, I think this is where you will find the problem. The intake clogged or the head ports clogged. Don't assume the intake is clean based on what you can see - clean it or replace it with a clean one. I don't assume they are clean until after I pass a 3/8" cable with a frayed out end through all the passages, driven by a drill.

I also had one car that was almost completely plugged inside the head intake ports. There was a solid cylinder of gunk on top (backside) of the intake valves.

Another thing I would check was that the oil drain was good from the turbo. Oil drain line not clogged and also that the crankcase was not pressurizing. How does it run with the oil cap off?
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
La Conner, WA
TDI
... None :S
What does the MAF see? What is the IQ? I'd thing with soot chunks that big (How do those make it through the cat anyway???) you'd be able to find something really out of spec.

Is the goop on the upper end holding the valves open :eek:

Just thinking aloud here...

You've exchanged with known good:
-IP
-Computer
-Maf (or disconnected)


What hasn't changed?
-Wiring harness (giving bad feedback from a sensor?)
-Injectors?

So you're getting tons of fuel (too much) but it won't rev? That sounds like fuel at the wrong time.

-J
 
Last edited:

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
La Conner, WA
TDI
... None :S
Are the plugs on the N75 and N18 flipped? Is the EGR valve leaking somehow?

You mentioned you unhooked vacuum lines. Did you try with everything unhooked?

Could the VNT vanes have been really stuck and made a ton of backpressure at idle?

-J
 
Last edited:

bhtooefr

TDIClub Enthusiast, ToofTek Inventor
Joined
Oct 16, 2005
Location
Newark, OH
TDI
None
I'm kinda wondering what happens if you remove both manifolds, block off the turbo oil feed line, and try again, actually.

I've run a TDI with no MAF or MAP at 4000+ RPM (couldn't get the upper intercooler pipe reinstalled, had to drive to get it installed with no pipe there, and when the thing is running in limp+naturally aspirated, you need revs to get onto the freeway), so it can be done.
 

JC_1992

Veteran Member
Joined
Mar 6, 2010
Location
Grand Rapids, MI
TDI
2002 Jetta GLS, 2001 Jetta GLS
After seeing what was under the valve cover I would Da** near give up on this car. Definitely check the intercooler and intake manifold for build up.

Replace the turbo oil feed line or if you can remove it without breaking it then clean it out with wire pipe brush and degreaser.

I would also remove the oil pan, look at the bottom end, and clean/remove what you can.

Have you tried unplugging the EGR valve (vac hose on top)? At last years GTG one was stuck open and began pouring out soot.
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
Working backward in answering questions posted:
Intake and exhaust manifolds are both clear. They were bottle-brushed through when they were off.
The back sides of the valves are also clear. I left the cam and followers in place the second time the head was off in order to permit rotating the cam to hold each valve open in turn for inspection. A light underneath (piston area) showed through into the manifold port with very little obstruction except a slight surface coating of soot.
I've tried with the exhaust open after the turbo by disconnecting the down pipe. I've tried with the inlet open by disconnecting just before the anti shudder valve.
The manifolds are clear, anti shudder is open, EGR is closed, turbo spins at idle.
VCDS output checks show the N75 and N18 are connected to the proper actuators and are operating correctly.
VNT (after I cleaned it) begins moving at 5 inches of vacuum, and is fully open at about 15 inches, smooth response in between.
Injectors have been changed with known good ones (1Z/AHU 220 bar Sprint 520 formerly used in my Cabrio).
Valve sludge has been almost completely cleared out now. I'll eventually drop the pan and wipe out anything that may still not be thinned out and drained, but the top end and turbo lines are clear and goop free.
IQ is about 5.
Runs the same (1800 rpm lots of smoke) with the oil cap off and the crank vented to atmosphere, slight vapor mist from the oil fill port but I suspect that's residual from the de-sludge treatment.
Rotating the engine by hand (19 mm socket on a 9 inch ratchet on the crank nose) seems no more difficult than any of the 1Z/AHU I have extensive experience with, the BHW that I wish I didn't have experience with, or the few ALH I've worked on.

It hasn't been asked yet, but piston protrusion above the deck is equal, no 'dead spots' of pistons NOT moving as the crank is rotated forward and back (con rod play is non existent), no odd noises when it idles. Loosening one injector fuel nut at a time (shutting down each cylinder) shows no dead cylinders.
The cam, followers and turbo will need to be replaced, but I don't think these easy fix items are causing the main problem of no engine speed.

The wiring harness has not yet been rung out, but VCDS shows no anomalies.
Accelerator pedal shows smooth response form 0 to 100%, boost request and actual are within a few units of each other.
I'll check the MAP results again as I don't recall them off the top of my head.
 
Last edited:

Seatman

Top Post Dawg
Joined
Apr 23, 2010
Location
Scotland
TDI
2014 Skoda rapid elegance 1.6 cr tdi
What about the timing? How does it look when the car's revved up?
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
What about the timing? How does it look when the car's revved up?
When it's revved up? I wish I could tell you, but it won't get over 2k rpm no matter how long I hold the pedal to the floor in neutral.
Cam and crank timing are dead nuts. Injector pump timing was originally slightly retarded (within spec), and is now slightly advanced (within spec).
 

compu_85

Gadget Guy
Joined
Sep 29, 2003
Location
La Conner, WA
TDI
... None :S
I wonder how hard it would be to make an umbilical to hook this engine up to another car...

I'd probe the quantity position sensor at the IP and at the computer.

-J
 

Seatman

Top Post Dawg
Joined
Apr 23, 2010
Location
Scotland
TDI
2014 Skoda rapid elegance 1.6 cr tdi
He tried the other pump in the car already and the ecu so that rules them out.

This must be a physical thing with the engine or one of the sensors is pooped but isn't coming up for some reason. I would try the crankshaft one anyway seeing as that's fairly easy. What other ones are there?
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
Probe the quantity sensor? How?
I can ohm out the harness between the pump and the ECU, but a known good pump (her 11mm) and a known good ECU (her RC3 no EGR, immo-delete) installed in my car didn't change anything.
My 10 mm pump in her car worked just fine with her ECU. My ECU is stock and still has immobilizer active so about 2 seconds is all I can get, but in that time before it shuts everything down my ECU and pump will spin hers up to about 3k rpm.

crank sensor? Is this also used for tachometer? the cluster tach and the VCDS tach display read the same and respond equally.
 
Last edited:

bhtooefr

TDIClub Enthusiast, ToofTek Inventor
Joined
Oct 16, 2005
Location
Newark, OH
TDI
None
I think he's meaning, probe the voltages. See if the signal is getting changed between the ECU and the pump.
 

DanG144

Top Post Dawg
Joined
Aug 2, 2007
Location
Chapin, South Carolina, USA
TDI
2005 A4 Jetta 5spd
There was one car locally that had a damaged crank sensor wheel (reluctor wheel) that caused poor operation. In this car it did show an injector imbalance. It actually took looking at the signals with an O'scope to see the problem. Then pulling the pan showed the damage. Apparently in the past it had a bent rod where the piston bent the reluctor.
 

Seatman

Top Post Dawg
Joined
Apr 23, 2010
Location
Scotland
TDI
2014 Skoda rapid elegance 1.6 cr tdi
crank sensor? Is this also used for tachometer? the cluster tach and the VCDS tach display read the same and respond equally.
Not sure what all relies on the crank sensor, just trying to think of free and easy things to try, at the moment I'm a bit baffled lol. But something is stopping the car from revving freely and the last time I seen that was the #3 lift sensor on my car but you tried good injectors and ruled that out, you also ruled out the ecu and pump, you've checked all the pipe work including the exhaust. My thinking is maybe a sensor is bust, it's better than my other theory of the cam being a bit siezed but you probably checked that when you had the head off.
So yeh, baffled
 

greengeeker

Vendor
Joined
Feb 8, 2006
Location
Cambridge, MN
TDI
2002 Jetta GLS
Can you log SOI, IQ, RPM during this stumbling/smoking?

I know it's a PITA but can you pull the crank sensor to see how much sludge is visible through the hole and on the end of the sensor? I wouldn't be surprised to find metal flakes or other debris in the sludge that would interfer with the sensor.
 

migbro

Veteran Member
Joined
May 19, 2010
Location
Lincoln, Mass.
TDI
2003 Golf GL
My 2 cents. Blocked catalytic converter. Your engine won't rev up because the exhaust gases are exiting through a drinking straw.

Also, I've been wondering if anyone has tried Auto-Rx in a sludged ALH. Auto-Rx is not a solvent type cleaner like Seafoam, it's a mix of esters, primarily lanolin, that supposedly dissolves the sludge over time. If you try Auto-Rx please let us know how it goes.
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
Can you log SOI, IQ, RPM during this stumbling/smoking?
Red is RPM, scale is 0 to 3000, each horizontal line is another 300.
Green is injected quantity, scale is 0 to 50, each horizontal line is another 5 milligrams per stroke.
Yellow is start of injection (requested), Blue is start of injection actual, scale is -10 to 10 degrees, each horizontal line is 2 degrees with zero in the middle.

Chart shows a few moments of idle, a few moments of immediate WOT and held, a few more of idle, a gradual application of pedal to WOT, another period of idle, another quick WOT, and back to idle.



This embedded image is a medium size. Full size (requires logging on to the TDI picture server) is here: http://pics.tdiclub.com/showfull.php?photo=86227
 
Last edited:
Top