ALH Turbo Delete: Daily Driving a Naturally Aspirated 2001 Golf

[NarfBLAST]

"Don't worry, this is only temporary...

...unless it works." - Red Green.


I blew my turbo and I decided not to replace it right away. Instead, I wanted to try natural aspiration:

All of the hard work is already done, I have:

- Removed most of the intake pipes, broken turbo pieces, intake manifold and exhaust manifold.

- Removed the oil feed line to turbo and replaced the banjo bolt with a shortened regular M12x1.5 bolt and one copper washer to seal the outlet at the oil cooler:





- Removed the VNT vanes and their backing plate from inside of turbine housing to allow free exhaust flow:



- Remove turbine shaft and replace with a lower control arm bolt, nut and an aluminum crush washer





- Reinstalled the center cartridge into the turbine housing and made a block off plate for the oil return flange on the bottom of the turbo:



- Reinstalled the exhaust manifold with block of plate between it and the oil return line.

- Finally, I reinstalled the intake manifold and connected it directly to MAF housing using a piece of shop vacuum hose:



I'd guess I have about 30 hp available now and the check engine light is on for boost control. I have Bosio Sprint 520 injectors and a RC3 tune. Zero to sixty takes 30 to 40 seconds, but I can putter around town no problem. Also, once up to speed on the highway, it is easy to forget there is a problem. Some torque seems to be available between 1500 and 2000 rpm but above that there is little to no power.

I will have to get some larger intake tubing: right now I am using 1" inside diameter shop vac hose and I just realized that if I upgrade to something closer to the 2" diameter of the race pipe, the cross sectional area would be almost five times larger!

Will post updates.

Update September 2021 still going strong! Adding simplified Vacuum drawing:

 

[UhOh]

OK, Paul, the obvious question: Why?

Someone else on this forum did this.

This starts to verge on being unsafe:

All the work (lots of time to bother DO and UNDO) it would seem that that it would be cheaper to have just dropping another turbo (can get a blessed one pretty cheap).

 

[NarfBLAST]

I did it because it was easy and cost almost nothing.

Also, I heard that there was a tune for turbo delete and I am trying to get in contact with someone local who can load it for me.
Link: Stage 0 Tune Now Available (Natural Aspiration) - TDIClub Forums

edit: I don't want to spend any money on this car because it is long overdue for the scrap heap.

 

[Rembrant]

So what happened to your turbo? Didn't you install a new Mahle VNT15 a couple years ago?

 

[Andyinchville1]

Turbo , Turbo ? .......We don't need no stinkin' turbo....

I recently, bought a VW beetle with a defunct turbo vacuum actuator....No real power but doable if you're not in a big hurry....

FWIW - I am looking forward to fixing the power issue tho! ;-)

Andrew

 

[Golfrunner]

Had given this a thought myself when my ole 2001 Golf kept going into the dreaded and emasculating "limp mode".. A new actuator eventually solved the problem and I sold the car a few months ago working fine. 365k miles on original turbo.
Report back with your mileage if you could. Always wondered if it would increase - though you are way outside of engine design/useage I figure and would probably find a decrease.
Diesel on...

 

[burn_your_money]

Very nice SDI. All you need is the proper intake and exhaust manifold and you'd probably do pretty good. I had a AAZ that I converted to NA with lots of upgrades, it was quick but it was also in a mk2.

 

[jimbote]

an AZG exhaust mani would work nice on there, you could use the downpipe as well and a 1Z or BHW manifold would get you pointed in the right direction ... cool mod

 

[Enabled]

With a proper tune that raises the fueling a little more for the NA areas it can be a bit quicker. It would even be able to do over 130 km/h.

 

[jimbote]

what did you do about the map/iat sensor ?

 

[Growler]

what did you do about the map/iat sensor ?

he did say he has codes for boost control... likely its either unplugged or only reading atmosphere for pressure and IAT.. the intercooler is likey too buried to have been removed at this point. I know I wouldn't have removed it..

NARF, don't let the naysayers sway you. this is a fun thread and if you feel the car is relegated to let's just have fun status, good on you!

 

[Oo-v-oO]

Anybody that thinks this is unsafe due to lack of power has never experienced an A2 Jetta with all of 52 hp out of a NA 1.6 IDI. ?

Sent from my XT1060 using Tapatalk

 

[NarfBLAST]

what did you do about the map/iat sensor ?

Good question! Like Growler guessed the MAP is still in the intercooler which I didn't feel like removing just yet. It will read atmostpheric pressure since the intercooler is open with some rags stuffed in it. It also gives a temperature reading off the stagnant air inside of it. I guess it could be moved into the intake tract later if I was feeling ambitious. I wonder if that would make a difference?

Right now I really need to get a bigger intake hose; I will be heading to the hardware store today.

Also, I am not sure if it is in limp mode right now or this is just turbo-less operation. Do RocketChip tunes affect the behavior of limp mode? I emailed Jeff to let him know what I was doing and ask if he had a tune for this and he quickly replied saying compression would need to be increased, and work done to the head, to get any power out of it. He also said something about "undoing 20 years worth of evolution in diesels". I understand what he is getting at. I don't think Jeff has time for stuff that doesn't have more power than stock, so I won't waste his time with more emails.

Thanks to everyone for checking in, all opinions are appreciated.

 

[Oo-v-oO]

It would be interesting to compare engine specs such as CR between the SDI and TDI.

Sent from my XT1060 using Tapatalk

 

[Genesis]

NA diesels typically do run materially-higher compression. Detroit 2-stroke engines are definitely this way; most of them were available in both "natural" (not really; there is still a blower!) and turbocharged versions.

 

[AndyBees]

When my ALH Vanagon Turbo goes to "limp mode" it will not fall out of a tree! The Turbo boost gauge will actually show a bit of vacuum when revving the engine while in limp mode.

In this Thread, part of the project pieces would be good to have on board during a long trip in the event the Turbo blew, such as the bolt to block off the oil-feed steel line port at the oil filter.

Seems there was a Thread about someone trying to limp home going from Texas to Colorado with the Turbo gutted....

 

[Votblindub]

When I was helping my friend buy a daily beater wagon, the owner said the turbo broke. I have my spare vnt15, so we got the car. Turns out we had to make sure the actuator was stuck. Anyways, while the turbo did nothing, my friend drove his n/a(kinda) and hated it. Partially because he's used to driving a high revving n/a 80's corolla, that's responsive and mechanical and partially due to feeling like a huge hazard & hindrance in the road. There was a severe lack of acceleration, so going onto the highway for daily driving was a bit dangerous. Even at the floor, it would barely move. It's scary to drive in traffic.
Also, i'm stealing the "wouldn't fall out of a tree" expression.

 

[NarfBLAST]

Seems there was a Thread about someone trying to limp home going from Texas to Colorado with the Turbo gutted....

That was a really great thread! Turbo blew in Texas....stuck need help! - TDIClub Forums

 

[NarfBLAST]

Update: One Weak Week Later...

Still puttering around, now with slightly more power!

Intake upgraded; went from 1 1/4" to 2 1/2" shop vac hose:



I'm really glad I bought a spring clamp tool, it is a pleasure to use:



Larger intake hose installed without the size reduction adapters, also, no duct tape:



Right away I noticed more power between 2000 and 3000 rpm. Maybe 40 hp peak now?

There is a measurable improvement in airflow on the Scanguage. It used to report a MAF reading that topped out around 38 grams per second (g/s) before 3000 rpm. Now it reaches over 40 g/s before 3000 rpm and as it is actually worth revving out to just over 3000 now. It tops out around 42 g/s over 3000 rpm. For comparison a stock engine should reach 80 g/s at 3000 at peak boost per the TDI FAQ. I used to see numbers over 100 g/s over 3000 rpm.

I can actually climb all of the steepest hills within 20 minutes of my home at safe speeds.

One other thing I noticed is that the exhaust smells better than it has in a long time, smells like new, maybe because I am under-fueling? I have a fix for that...

 

[jimbote]

i'm interested to see what your economy numbers will be ... are you going to keep track ?

 

[IndigoBlueWagon]

Interesting project. I wonder if it would run better if you unplugged the MAF. Right now the MAF is probably reading very low air volumes because of the lack of boost. That will deliver low fuel. Unplugging it may give you more fuel and a bit more power. Does the car smoke at all now? If not it's certainly under-fueling.

 

[Growler]

Interesting project. I wonder if it would run better if you unplugged the MAF. Right now the MAF is probably reading very low air volumes because of the lack of boost. That will deliver low fuel. Unplugging it may give you more fuel and a bit more power. Does the car smoke at all now? If not it's certainly under-fueling.

I agree. try running it with the MAF unplugged.. if you aren't seeing MAF readings of 500-550 in vcds while driving, your computer is pulling fuel (and power) if you do ever see numbers higher than that, at low normal driving RPMS, then perhaps its worth keeping the MAF plugged in. my guess is it will feel like you chipped it (comparatively LOL) just by unplugging the MAF.

 

[UhOh]

But, BUT... unplugging the MAF will put you in limp mode! (sorry, couldn't resist but, great call by Peter!)

 

[NarfBLAST]

i'm interested to see what your economy numbers will be ... are you going to keep track ?

I will definitely be keeping track! Fuel economy seems pretty good right now as I've got over 700 km on the this tank and the fuel guage is near the half way mark. I should really fill up soon. This tank is a mixed bag of pre-turbo delete with some towing and some time on the smaller intake hose.

I don't trust the Scanguage to report accurate fuel economy numbers right now, it tends to need to be re-calibrated depending on driving style and trip type. Also, I've just transistioned from "takinging the kids to and from school every day" to "summer randomness". I also find the scanguage needs to be reclaibrated any time an engine parameter is tweaked. I do put some faith in the in the instantaneous Scangauge reports of fuel consumption and it seems like fuel is limited to less than half of what it used to report when more throttle is requested.

I need definitely need to do some logging with VCDS to see what the MAF readings are. Thanks for the suggestions Peter and Aaron. I think it should run better with the MAF connected but have to admit I haven't check the numbers yet. I agree that if the MAF is reading low then it might as well be unplugged. Then again, it is sort of hard to fool the ECU when the MAP is still connected, I might try unplugging that too at some point.

Ideally I should load a tune that supports natural aspiration, but that would cost money and I'm not done experimenting yet!

Besides:

The car it is actually seems to be running pretty nice, the more I drive it the more confidence I get! I had the unique opportunity to drive my wife to Toronto early yesterday morning with no kids in the car. It was lovely! We kept up with traffic just fine on the relatively flat trip on the Queen Elizabeth Way along the shore of Lake Ontario. We reached speeds of 130 km/h (80 mph) and at no point did my wife feel "unsafe". Occasionally I would let out a Jeremy Clarkson yell of "POWER!!!" as I planted my foot on the accelerator and nothing much happened. YET, we always kept up with traffic, and got to our destination and home safely.

The phrase, "Drive more, worry less" comes to mind.

I was going to re-install my old PSI-Powerbox on the injection pump harness to get some more fuel, but I haven't done that yet just because its driving quite adequetly right now and I would like to collect some data first.

To Do List:

- Collect and post MAF data using VCDS
- Refuel and post fuel economy numbers
- Consider modifications such as unplugging sensors or installing the PSI-Powerbox

 

[AndyBees]

It's no longer a TDI ........ so, you need to move this Thread to another forum category.....

Very interesting.... Will be following to see the stats!

 

[jimbote]

It's no longer a TDI ........ so, you need to move this Thread to another forum category.....

Very interesting.... Will be following to see the stats!

it's still a TDI... Turtle Direct Injection

 

[NarfBLAST]

Fuel Economy Looking Good So Far

I had just enough time tonight to go for a drive to the gas station before I had to be home to help my wife get the kids and her sick Grandma to bed.

As mentioned before this was a mixed tank which included driving with turbo, but mostly without turbo.

Drove 715.8 kilometers and used 37.908 liters so this tank calculated: 5.3 L/100km or 44.4 mpg!

Looks promising considering I was consistently seeing on previous tanks: 5.9 L/100km or 40 mpg.

I also gathered some interesting MAF data, and did attempt to drive with the MAF disconnected which had a very interesting result. Will try and put the raw VCDS data into a nice graph before I post what happened.

 

[NarfBLAST]

MAF Disconnect, Your Mileage May Vary

I tried to graph MAF vs RPM but it wasn't pretty.

All I really needed to know I could tell just from looking at the live measuring blocks: MAF actual never exceeds 500 mg/stroke and it actually goes down below 400 mg/str over 2000 rpm and trends lower as RPMs rise. At first I was really confused, because I was used to my Scanguage which reads grams per second and always trends upward until it peaks out. Then I remembered that mg/str is a function of mass air over RPM instead of mass over time and if mass air can't keep up with RPM then the number will fall off.

Disconnect the MAF and see how it runs you say, don't mind if I do! After all, the default MAF reading should be 550 mg/str across the rev range right? That is what I remember from when my ECU was stock, but with RC3 it seems that Jeff has inserted a new default: 1275 mg/str.

It rolled coal. It was just after sunset but I could clearly see that headlights behind me were dissappearing in clouds of black smoke. Was performance improved? Maybe? It was hard to tell with such a short test. The smoke was unacceptable and I quickly pulled over and reconnected the MAF. Maybe I can test some more one day when I have more time.

So I learned that Rocketchip puts a ridiculous value in for MAF actual when the sensor is disconnected. That is fun and relatively harmless I guess.

Now I wonder what happens if I disconnect the MAP sensor? I would guess Jeff would put a safe value in there, or the workings are entirely different and there is no such thing as a default MAP value.

Would be nice to hear from someone with a Malone Stage Zero tune but I'm starting to wonder if they actually sold any? I read somewhere that they added the NA Stage 0 to their menu only because one high profile customer requested it as a temporary thing so they could move a car around while building a custom turbo setup.

 

[Growler]

RC uses 1275 as a default so that at no time will the ECU pull back fueling due to a lack of airflow... makes it real fun with a turbo in there, but NA.. I imagine its a cummins style smokefest. that is unfortunate.

I wonder if you could switch over to the Auto MAP on the ECU (basically the opposite of what the Auto-Manual swap guys do) as a test to see if he has fiddled with those maps as well and report how it runs with the MAF disconnected. (you will get CELs for missing TCU and perhaps a few other things, but it should still run)

 

[NarfBLAST]

I wonder if you could switch over to the Auto MAP on the ECU

Okay, I'm interested, but I did some searches and couldn't find anything. Can this be done with VCDS?