ALH Driveability Issues

I have two problems with my ALH:
1. Fixed Every time the first time I go to accelerate with the car in gear clutch out, the engine will rev up to 1300 or so and then back to idle, with my foot still partially on the throttle. If I put my foot down further nothing happens. If I take my foot off then put it back on again, everything is normal. I can rev the engine out of gear to any RPM, but once in gear and moving it will hold back that first time. Very annoying when pulling out of parallel parking.
Possible Solution 1: Hooked up the brake light switch signal to the ECM.
Possible Solution 2: Hooked up the brake cruise cancel to the ECM.

2. My engine shudders between 1000-1300 RPM or so. When I'm trying to crawl in a parking lot or traffic in first or second gear the engine will start to buck a little and get worse if I try to accelerate slowly. If I accelerate above that RPM range it's fine. It feels like if you went from first gear to fourth accidentally instead of second, at low RPM. It's done this since day 1.

Only other issues are maybe ticking lifters; I don't have any engine bay sound deadening so it could be a normal sound, and boost deviation three times. I'm certain that's from a worn out vane control.

Info/troubleshooting so far
A. The car is a 79 Rabbit with a 99.5 ALH 210k miles from a Jetta manual, running the original 020 with an 8V 210mm flywheel. Could a flywheel of the wrong weight cause the bucking (I'm assuming it's not the stock weight)? Also the timing mark does not line up. I painted on a line on the flywheel but maybe I got it wrong. I can pull a glow plug and check. How far off can the crank be before seeing issues?

B: Could it be a fueling issue? I changed the injectors, VCDS shows they're in range. The plunger above the fuel inlet on the pump is all together. I just put in a junkyard 11mm pump yesterday, issues are still there. It came out of the junkyard car very shiny, only a little bit of dirt on the bottom, no leaks. Didn't check anything on the pump before installing it. IQ set to 3 on the old pump and the new through VCDS. From memory not a lot of bubbles in the fuel lines.

C: As for wiring, only running engine required stuff is hooked up to the ECU. No cluster, no brake light signal, no cruise, clutch safety is shorted, no cabin stuff, radio, airbag, etc. My friend put an ALH from a 98 NB into his Caddy with the cluster from my 99.5 Jetta, power steering, A/C, and he's working on ABS right now, no cruise, clutch shorted, and his car does the first acceleration slowdown too.

D: Timing belt? I had to delete the roller below the tensioner to fit my motor mount, and so I guess the tension. Normally it's set to where the notch lines up with the tab on the tensioner. I set it tighter by going just past the notch. Is this too loose still? One day I did try and go past by one width of the notch and there was no difference, so I set it back.

E: Harmonic balancer bad? Any way to know without getting a new one? I do have a new transmission whine...any danger in pulling off the balancer and firing it up, let alone drive it around?

F: Alternator pulley? I can see the tensioner bouncing up and down. I'll pull the belt off and drive it around the block.

MAF. Disconnect your MAF and see if that makes any difference in steadiness: if you unplug a bad MAF the engine should run smoother and steadier but will run like you don't have a turbo (it's essentially in limp mode).

Wife's car's MAF totally crapped out this past year. Car was bucking like something really horrible was going on. With the car still running I unplugged the MAF and instantly the engine settled down and was perfectly drivable (though gutless). New MAF installed and it was back to running perfect again.

My car has great power even with these issues. I will try unplugging the MAF though.

The first week of the swap it was in limp mode; I had a broken wire to the pump connector. It's definitely not in limp mode now, especially with the 11mm pump. If it is, then I can't wait to get out of limp mode!

I have also experienced boost deviation where the vane actuator was funny, and no boost, where the harmonic balancer wore through the lower plastic charge pipe and I was rolling coal, but going slower than the 1.5L that used to be in it.

jackfolstam said:

D: Timing belt? I had to delete the roller below the tensioner to fit my motor mount, and so I guess the tension. Normally it's set to where the notch lines up with the tab on the tensioner. I set it tighter by going just past the notch. Is this too loose still? One day I did try and go past by one width of the notch and there was no difference, so I set it back.

Click to expand...

WHAT?

You do NOT mess around with this stuff. You set it "by the book" and you leave it. At this point I have absolutely no idea what the situation is with your timing. Unless you can verify/confirm that your crank, cam and IP all line up as per proper VW settings everything else is but shifting sands.

Just to be clear, I do the timing by the book. While the locking tools are in, while the cam and IP gears are loose, and while the flywheel is at TDC, then turn the tensioner to the notch...then a little bit more. Then tighten everything, take out the locks, check the timing digitally.

The old engines had a wide range of tensions that were acceptable, when there weren't auto tensioners, and the popular opinion was more loose was better, to not wear out the IP bushings/bearings. People only worried about debris causing a jumped tooth not a loose belt, and some brave people took off the timing belt covers because they thought it looked cool.

Posts 7, 8, and 10 are interesting:
http://forums.tdiclub.com/showthread.php?t=197539

So it might be that the slowing down is the "not allowed to do a brake stand" software, which I remember reading about one time or another. Isn't there also a service where you can get this programmed out? Can I do that myself with VCDS? Otherwise I will actually put the brake switch signal into the computer.
I remember researching when first doing the wire harness for the swap that someone was theorizing that the brake light signal was for the idle to be bumped up due to 7 brake light light bulbs turning on.

Looks like you can't change it via VCDS on a MkV so I bet you can't on a MkIv. Source:
http://forums.vwvortex.com/showthread.php?6116643-Enabling-Left-Foot-Braking

I've also been reading about how the clutch switch not only controls the cruise and starter interlock, but also changes the torque and throttle response for shifting, on other VW and Audi websites. Is that true for the ALH or is that just gas cars? Looking at the Bentley wire diagram I don't see a direct connection from the starter interlock relay to the ECM. The starter interlock relay is connected to the J393 Central control module for comfort system, but that isn't included in the "Diesel Turbo Direct Injection, overview" schematic, so I don't see how it would affect the engine control if not connected to the engine wire harness.

Had similar bucking/surging on my AHU. Also had IQ wandering all over and timing jumping around at idle. Tried new nozzles, various IQ settings. Ultimate fix was a different pump.

Still don't know what the problem was. Some day I plan to take the QA apart and see if there's debris between the armature and stator.

On your revving issue maybe something to do with the clutch switch or brake pedal switches? Are they wired to the ECU properly? You have the right go pedal position sensor?

jackfolstam said:

Just to be clear, I do the timing by the book. While the locking tools are in, while the cam and IP gears are loose, and while the flywheel is at TDC, then turn the tensioner to the notch...then a little bit more. Then tighten everything, take out the locks, check the timing digitally.

The old engines had a wide range of tensions that were acceptable, when there weren't auto tensioners, and the popular opinion was more loose was better, to not wear out the IP bushings/bearings. People only worried about debris causing a jumped tooth not a loose belt, and some brave people took off the timing belt covers because they thought it looked cool.

Click to expand...

You have an ALH, not the same as the "old engines." IF this is not an ALH then please correct me: your original posts suggests that it is. NO ALH will have any significant slack in a TB: and none should have any missing rollers or missing anything else.

BTW - The tensioner is turned till it's in the middle (not "a little bit more"). I can also recite procedures but that doesn't translate to me actually doing them to the letter: sometimes I mess up; I always approach problems like I was responsible for them, that I may not have done something right; this approach forces me to PROVE my work.

UhOh said:

You have an ALH, not the same as the "old engines." IF this is not an ALH then please correct me: your original posts suggests that it is. NO ALH will have any significant slack in a TB: and none should have any missing rollers or missing anything else.

Click to expand...

I meant that when there were no auto tensioners, that a wide range of tension was acceptable.
The tensioner on my ALH has a spring in it so it must be able to accommodate a few different settings, a little more or a little less than spec. Not much, but a little. My belt does not appear to have any slack in it. I can compare it to a coworker's ALH and it feels the same to the touch, but I admit that is an inaccurate and imprecise way to measure it.
My original post states that I have an ALH, not suggest it.

UhOh said:

BTW - The tensioner is turned till it's in the middle (not "a little bit more"). I can also recite procedures but that doesn't translate to me actually doing them to the letter: sometimes I mess up; I always approach problems like I was responsible for them, that I may not have done something right; this approach forces me to PROVE my work.

Click to expand...

I turn it a little more because if I didn't, there would be slack in the belt due to not having the roller below the tensioner. If I didn't then the tension would be lower than spec. Saying tension this many times makes it sound weird now.
I've read about some miracles where people find their TB, or a TB on a car for sale, to be so loose for however thousands of miles that you can put your fingers between the belt and the rollers, but they don't skip time or have any other driveability issues. My TB is no where near that loose.
So when researching the engine swap it seemed commonplace to delete this roller. I hadn't seen anyone else complaining about my issues. So, I thought it was a reasonable thing to do. It's a lot more difficult for me to modify my car to accept the original engine mount, so here I am, asking for help. I just hope that someone else comes in here and says that they don't have this bucking issue with a similar setup to mine, or another cause for the issue, so I don't have to change the mount.

KLXD said:

Had similar bucking/surging on my AHU. Also had IQ wandering all over and timing jumping around at idle. Tried new nozzles, various IQ settings. Ultimate fix was a different pump.

Still don't know what the problem was. Some day I plan to take the QA apart and see if there's debris between the armature and stator.

On your revving issue maybe something to do with the clutch switch or brake pedal switches? Are they wired to the ECU properly? You have the right go pedal position sensor?

Click to expand...

I just added the brake switches tonight, and it fixed the slow down issue!
I got 000 on VCDS cruise control monitoring, and I can get 011 when I press the brake pedal!
I also put in a 'kill' switch for the clutch, a hidden switch under the dash. I thought for the first half of the drive where I turned off the switch the revs didn't hang between shifts, but I stopped on the drive home tonight, reset the car and left the switch on after starting, and didn't really notice anything different. For the past week or two I noticed the RPMs were hanging and I had to wait a moment for them to drop or the car would surge forward as I shifted.
Unfortunately and expectedly, the jack rabbiting is still there .

Thanks for clearing up the confusion. Adding in something that's not relevant to your current issue muddied it all up.

UhOh said:

Thanks for clearing up the confusion. Adding in something that's not relevant to your current issue muddied it all up.

Click to expand...

Well it's still a doubt of mine; I brought it up in case someone has had the same experience, or through their experience, can rationalize why it could be a problem. I am certainly worried about it, but it's really one of the last things to check off of the list. I mean, I'll swap in the 02J and the proper flywheel before I change the engine mount bracket.

Speaking of engine mounts...I'm going to swap in some home made front and rear HD mounts tomorrow. I bought some new stock mounts and filled them with RTV. Not as stiff as window weld but same shore hardness as the rest of the rubber. I had them in for a few days before I couldn't stand the vibrations; I couldn't put my head on the headrest for a few seconds until I felt sick. But, I just increased the idle to max (943 or 945 or something weird) through VCDS. At idle I can see that my horn button isn't vibrating like crazy any more, but it has started a new harmonic with a piece of trim behind the driver's door...the thinking is that maybe there's a harmonic frequency between the engine and the way it's mounted that creates the resonance right there at 1050 RPM or whatever. Maybe if I don't allow it to start the bucking, or if it's trying to shake the entire car instead of just the drivetrain, the resonance won't be there.

I wonder whether a fluid damper would have any significant impacts on vibration? I've run too much small equipment that generates vibrations, couldn't stand it in a car!

I also hate messing with the engine mounts. Did a Time-Sert on the one in my car, in-place (in the middle of winter as I was doing my TB, outside).

Have you perused the TDI Swap Forum on this site to see what others have done with that swap?

KLXD said:

Have you perused the TDI Swap Forum on this site to see what others have done with that swap?

Click to expand...

I did for many months researching whether I wanted to swap or not and with what, and then more once I got the engine, on how to get it all ready so I could drop it in with as little headache as possible. But, there's always more to learn.
The thing about that forum is, where are all of the posts? There's less than a page of threads. Are they deleted after a while or are there really that few swaps? I mostly visit VWVortex for the MkI info, and here when I need the ALH info.

Did you go to the bottom of the page and set the Display Options to "Beginning". Seems to default to "Last 2 Weeks".

KLXD said:

Did you go to the bottom of the page and set the Display Options to "Beginning". Seems to default to "Last 2 Weeks".

Click to expand...

Thanks, tried it out, so much more to read.

I put in the front stiffer motor mount without much difference. I'll put the stiffened rear transmission mount in tomorrow probably but I seriously doubt it will do much at all. BUT, I did see that my oil cooler had a mist of oil on the top and bottom, so I thought the seals were leaking a little. But I realized I put the radiator shroud back on...

(you can skip this paragraph if you want) I got a low profile fan for the swap and zip tied it straight to the radiator because of clearance issues with the oil cooler and radiator hoses. I put it back on a few weeks ago because I thought I was running a little hot, and that the shroud would help. Going up a steep hill the bluetooth OBDII thinger was telling me 208 at the very top of the hill. I have a standard thermostat 195deg F, and I think a 203deg F (92deg C, stock for a 79 diesel Rabbit) fan switch. So I replaced the radiator at the same time because I accidentally put a hole in it... with one from a 92 Cabby and didn't want to mess up the fins with the zip ties to put the fan on.

I forgot about the clearance issues with the shroud and oi cooler...and tonight I hammered the shroud a bit to clear the oil cooler. The shroud and oil cooler never touched, but the wear marks are there, so they must rub when the car is accelerating due to the engine rotating under load. So, the stiffened engine mounts may solve the oil leak at least. The driver's side trim is rattling very loud idling in first in a parking lot now also...

one similar symptom

You describe:
1. Every time the first time I go to accelerate with the car in gear clutch out, the engine will rev up to 1300 or so and then back to idle, with my foot still partially on the throttle. If I put my foot down further nothing happens. If I take my foot off then put it back on again, everything is normal.

Sometimes, I press the clutch with left foot, and brake with right foot while downshifting and turning a corner, AND straddle my right foot to the throttle to match rpm for lifting clutch back off. I have done this for years on 5MT/6MT TDIs.

I get the same thing you describe- it will not come off idle unless I lift foot off, and press it on again

It breaks the smooth downshift, but mostly weird to have the engine "not respond" to throttle push, but JUST under those conditions as far as I can tell.

This is stock motor, new timing belt full kit, by reputable TDI mechanic (CoolAirVW) maybe 3500-4000 miles ago. I haven't bothered to ask him about it since it does not stall and otherwise all normal, with typical performance and power characteristics. No other odd behavior of issues at all.

MAF?

dubStrom said:

You describe:
This is stock motor, new timing belt full kit, by reputable TDI mechanic (CoolAirVW) maybe 3500-4000 miles ago. I haven't bothered to ask him about it since it does not stall and otherwise all normal, with typical performance and power characteristics. No other odd behavior of issues at all.

MAF?

Click to expand...

I have solved this issue by doing three things one evening, any one of which could have solved the issue. Note that I have swapped an ALH into a car that has no electronics hooked up the computer that are not related to the engine (radio, cruise control, airbag etc)
1. Connected the brake light switch to the ECM in the appropriate pin,
2. Connected the brake cruise control cancel permanently with a "brakes off" signal to the ECM in the appropriate pin, and
3. Put a switch in place of the clutch cancel instead of the straight bypass that I had before.

It's most likely I think that #1 did it, since for #2 I read about 'left foot braking' issues with early MkIV's (mine's a 99.5) and for #3 I can leave the switch in either position and nothing changes, other than not being able to start the car.

jackfolstam said:

I have solved this issue by doing three things one evening, any one of which could have solved the issue. Note that I have swapped an ALH into a car that has no electronics hooked up the computer that are not related to the engine (radio, cruise control, airbag etc)

1. Connected the brake light switch to the ECM in the appropriate pin,
...
...

It's most likely I think that #1 did it, since for #2 I read about 'left foot braking' issues with early MkIV's (mine's a 99.5) and for #3 I can leave the switch in either position and nothing changes, other than not being able to start the car.

Click to expand...

Jack, I edited my post above because it is when I press the brake AND then throttle with my right foot at the same time that this happens. The engine just idles! It is the ONLY time I observe this. I did not make that clear at all. Now your #1 change seems particularly relevant.
- It happens when I push the brake and then in addition, press the throttle to match rpm during a downshift. It is something I've always done with MT three pedal vehicles.

dubStrom said:

...when I press the brake AND then throttle with my right foot at the same time...

Click to expand...

I understand. My car had the brake "on," or so the computer thought, when the brake light signal was not hooked up to the ECM, so it was as if my foot was on the brake all of the time. When I would hit the throttle the first time of that startup, the ECM would limit the throttle, regardless if I had my foot on the brake or not.

Now with the signal hooked up, I need to try and do as you do, rev matching, or maybe brake boosting, or left foot braking, to see if the condition is still there, but working as VW intended it to.

dubStrom:
NOW I understand. I see what you mean; you have the stock 'problem' as designed by VW. I now have that issue.

So to get rid of it, can we remove the signal coming from the brake light switch, and simply ground it? Then the computer will always think the brakes are off, and it shouldn't affect cruise control, since that has it's own switch. Worst case scenario is that cruise won't work, and that a CEL will be thrown, if it checks to see that both brake signals are agreeing with eachother. Does the ECM do anything else with the signal? The only other decent theory I heard was that it will raise the idle because of the load from seven brake lights or whatever.

From your first post, first problem solved:

"1. Fixed Every time the first time I go to accelerate with the car in gear clutch out, the engine will rev up to 1300 or so and then back to idle, with my foot still partially on the throttle. If I put my foot down further nothing happens. If I take my foot off then put it back on again, everything is normal. I can rev the engine out of gear to any RPM, but once in gear and moving it will hold back that first time. Very annoying when pulling out of parallel parking.
Solution: Hooked up the brake light switch signal to the ECM."

Now, I wonder if I remove the brake light switch from the ECM, would I have the same transient unresponsiveness. That would be worse than the minor symptom I have now! I should explore the symptoms under other conditions, try to figure out exactly when it happens. I am usually preoccupied with a traffic situation when it happens. I would like to know, for instance, if I can push twice to get it to respond. That is a minor issue to live with.

dubStrom said:

Now, I wonder if I remove the brake light switch from the ECM, would I have the same transient unresponsiveness. That would be worse than the minor symptom I have now! I should explore the symptoms under other conditions, try to figure out exactly when it happens. I am usually preoccupied with a traffic situation when it happens. I would like to know, for instance, if I can push twice to get it to respond. That is a minor issue to live with.

Click to expand...

For me it would only limit throttle once every drive, the first time it's in gear under load. I could start it, pull out from parallel parking into traffic, and then my face would nearly hit the dash from me flooring it, from the car suddenly decelerating. I could also pull out of a parking space in a parking lot and idle to the stop light, but on the way floor it once so it limits power the first time, and then when I go on to the street it would be normal. If your car does this thing just once per drive, you could purposely trigger it before you expect to be rev matching.

Ya know, this is one of two things I miss from the 1.5L. I don't rev match with the ALH because compared to the 1.5 it feels very slow to rev, and seems pointless. I think that because I drive in the mountains, and because the 1.5 had such little power, that I was downshifting and rev matching all the time, and damn I was good at it (simply because I had so much practice doing it). I don't power shift because I'm still running the 020, and want to run it until I can afford a decent 02J clutch and all the other supporting swap parts.

The other thing was the sound. With the T3 and 2.5" straight pipe, the 1.5 sounded like a race car which made rev matching easy, and the ALH with the 2.5" straight pipe sounds like a Cummins (which makes people confused if they hear it first, and then they see it). Unfortunately with the 1.5 everybody wanted to race me, but I couldn't even keep up with a Vespa, except for downhill in the mountains.

I haven't been rev matching the ALH with the correct brake light signal hooked up, and thus I haven't had an issue with the ECM limiting power, so I don't think I will find a hack that will defeat that anytime soon (I've got other problems to solve).
If I were to try, I would:
First just disconnect and ground the brake light signal wire to the ECM and check via VCDS that the ECM always thinks that the brakes are off, and if yes then
Second drive around and if a CEL does not come on for brake malfunction, and also if cruise control still functions (and brake cruise cancel), if yes then
Third try brake and throttle at the same time. Well two and three can be checked in either order.

My friend did an ALH swap on his Caddy. Actually we met at the junkyard when I went to pick up the engine; we helped eachother with the swaps. I wrote the wire diagram, and had my car driving before his truck. He has the same 'slow down once' issue. Oops.

So, I texted him the specifics on hooking up the brake light switch signal, or so I thought. I accidentally sent him instructions on how to hook up the brake cruise cancel. It fixed the issue for him. So I guess I spoke too soon. However, we both have the implausible brake signal flashing glow plug light now.

So I guess that the computer checks for matching brake signals from the cruise cancel and the brake light switch, and warns the driver using the flashing glow plug light. I don't have the new dash and no custom GP light so I don't see this, but my friend does.

Anyone think the other issue in the original post, the car surging, could be the transmission? I suddenly remembered that the car did this mildly with the 1.5L, and then it was hardly noticeable at all once I turbocharged that, but now it's the same problem but much more violent.

I unplugged the MAF, no changes other than low power, felt the same as a boost deviation.

I finally got the extra 020 in. The noise is gone, but the shudder is still there. I will do the easier test next, and remove the alternator belt for a short drive.

Took off the alternator belt, then unplugged the MAF, but no difference. I also double checked my flywheel TDC mark. I painted a yellow stripe on the flywheel when the engine was out, that was off an 8V gas car, that I put on my 020 to get the biggest clutch I could get to fit in there. When I swapped transmissions the other day I got a clear view of how far off the permanent TDC mark is on the flywheel, and it's about 3/4" away. Double checking with the harmonic balancer TDC mark, my painted mark is well within range. The mark is in view at the timing window on the transmission, at both ends of the play that the harmonic balancer has.

So next is...02J or timing belt roller un-delete (change engine mount). I bought the 02J flange seals and input shaft seal, and the shift tower/cables, so I guess I better change the seals before I buy a clutch...I also think I want a Wavetrac, but will I ever need it? It can dump rain here, no snow. I don't *think* I'll ever buy a bigger turbo, let alone nozzles...