01 auto to manual car - MPG's still poor?

[Beammeupscotty]

Good day,

I have an 01 ALH Jetta sedan, 242k on the clock, that no matter what I seem to do only gets 35mpgs from when it was auto "all stock" (I can not confirm the car was all stock as it has had 10 owners and has indications of "modifications").

I got the car with a leaking injection pump about a year ago now, easy enough, replaced the seals and she started right up. I drove it for about 4 months as an auto while doing the maintenance for it before I found a 5-speed swap. However, I also bought some other stuff as the deal was good and I hate plastic "important" parts. Heres what all was done while I did the 5-speed swap.

DQY transmission (updated shift tower, axles and flanges)
SMF clutch (I come from BMW's and Ive had a DMF fail, not a fan)
Darkside intercooler with the upper charge pipe, the lower was meant for a VNT 17 so the lower charge pipe is stock plastic.
2.25" free flow turbo back exhaust with a single muffler ( not sure what the PO was doing with it but it seems like they just ran the PVC to the exhaust so there is a whole prob 2' from the turbo that I haven't gotten taken care of.
EGR/ASV delete
Intake Cleaned (wasn't bad build up)
New air filter
Radiator
New coolant sensors(no issues but they were cheap from FCP)
New coolant reservoir
new coolant hoses
New Tstat
New water pump
New Timing belt(and associated parts)
New fuel filter
New vacuum hoses
Reset Turbo actuator (starts moving at about 3" and hits the stop at 18") The car was over boosting when I got it so not sure how long that was messed up
Cleaned turbo with the oven cleaner method(no shaft play and the actuator moved freely. I was just playing it safe)
New head gasket and bolts
New seals in the trans (synchromesh Pennzoil)
New brakes (I checked with no dragging on any corner)
Tire Pressures are good and checked regularly

I've used OilHammers thread(and many other thread with this car, thank you everyone!) https://forums.tdiclub.com/index.php?threads/tips-for-fuel-economy.342274/
to help me try to figure out the MPG issue to no avail.

The only things in that thread I see as an issues are the wheels, Long Beaches, and not having the under tray on the car, I shift around 2500RPM and try to always be in the highest gear possible without lugging the car. My drive one way is 36 miles and I'd say about 28 of them are straight freeway, I run about 75-80(2500ish-2700ish RPM) depending on traffic for most of that. Still only 35MPGS!

The IQ was at 3.8ish and I have bumped it up to 4.8-5 yesterday.
Timing is in the center (thats where it was after the timing belt and I figured I'd let it ride for now) I'll advance it in a few days after I check if the IQ change does anything.
MAF reads as it should.
Turbo is still making the correct boost, it spikes to like 2100ish - falls back quickly to 1900ish
Injectors on VCDS indicate they are balanced correctly (low of -.40ish high of .08ish)
The Glow plugs are not working right now as I swapped the whole harness to manual and didn't have the correct block on the car to hook them up(but I live in GA and its still plenty hot to not really need them and the car doesn't hard start at all)
I always fill up at the same Murphy station usually about 13GAL (I don't vent the tank)
I have ran some red through it to see if that would change mileage but it remains the same.

I am 90% sure that someone before me was messing with this car, just not sure how much they messed with it as the actuator was out of spec and in VCDS the EGR was turned all the way down already, IQ was super high as well. Maybe thats as far as they went with it, I'm not sure but It could be possible it has injectors with no tune but I do not know how to Identify the injectors. (couldn't find a thread on it)

I know the larger Long Beaches will hurt mileage but I don't see them hurting it to below 40mpgs, they are a 225/50/17 tire. The car came with them on it, but I have a parts car with the small 15's I might throw some tires on just to see, weird thing is the speedo shows the correct speed per the various police speed checkers around town but in VCDS the KPH doesn't match? I doubt this is an issue but weird none the less.

The car smokes a good bit, I haven't ran any purge through it yet but thats my next step even though it doesn't see to be burning all the fuel as it sits so IDK if I even want more fuel in the chambers? Is there anyway to check the nozzles to see if they are stock auto nozzles or not? I have a set of manual injectors from the parts can I can swap in for experimental purposes.

I know it needs a tune with what I have done, and it will when I have the funds to do it all at once (nozzles, tune, maybe turbo)

The fuel mileage doesn't upset me to much but I am FOMO'd on seeing people with super high fuel mileage. I am concerned about the smoke even after the IQ bump and would like to burn that fuel if I can. I don't expect to break any records or even achieve 50MPGs but the low to mid 40's seems a reasonable ask from this car.

Thanks for any input as I am stumped. It is greatly appreciated as is all of the threads on these cars!

 

[Windex]

First, figure out or replace the injectors / nozzles. Big wildcard there.

What coolant temp do you achieve once the car is warmed up?

Is your mpg calculated from gallons pumped VS miles driven or from the MFA? Best to vent the tank and fill to the brim for consistency.

What psi does your boost peak at. Have you graphed requested boost VS actual?

Have you verified mechanical timing on the belt system in addition to injection timing?
Compression test?

 

[Beammeupscotty]

First, figure out or replace the injectors / nozzles. Big wildcard there.

I know! Any idea how to ID them?

What coolant temp do you achieve once the car is warmed up?

Fully warm is 194F hotter

Is your mpg calculated from gallons pumped VS miles driven or from the MFA? Best to vent the tank and fill to the brim for consistency.

gallons pimped

What psi does your boost peak at. Have you graphed requested boost VS actual?

my computer for whatever reason didn’t charge but I’ll have slme

Have you verified mechanical timing on the belt system in addition to injection timing?

yes

Compression test?

not yet though I’ve done the head gasket the head I know it’s good and there is cross hatching on the cylinder walls, but it needs to be done. I am doubtful it fails that.

 

[burpod]

assuming cam/crank timing has been verified... the next big thing is what injectors/pump are in the car - the automatic ones one would assume - 11mm pump and i believe the tiny ".157" nozzles. if not, needs a re-tune. it's also very possible the car might have different injectors and/or a tune already, which could be likely verified with a vcds 011 log

with egr delete, it should be also re-tuned to run optimally.

if everything is good, you should easily see 50mpg in a healthy 5spd alh!

 

[Windex]

If you google image search "ALH injector nozzle" you will see where the identifying marks on the nozzle are - they are located on the part of the injector that is held in place by the large cap-nut. Not visible unless you remove the injector and then disassemble.

Not hard, but you need to have a new crush washer and keep things very clean. Purists will say the nozzles will need to by properly calibrated for primary and secondary pop-pressure. Many have replaced nozzles themselves with no issue. best to ensure at the very least that you have proper spray pattern and atomisation.

Much debate on which nozzles are best, but most agree that bosch, bosio and firad make decent nozzles. try very hard to ensure you don't get any fakes if you do replace the nozzles.

even with the cross-hatch, a compression test is a good way to verify things are alright mechanically. If the compression is fine, you can put that to bed and concentrate on investigating other issues.

On your commute, I would expect at least 40-45 mpg from that car in proper running order if not more. My passat gets better MPG than your Jetta (it shouldn't) on a 10mi highway commute and occasional longer trips. that's with a much heavier car and a larger 2.0L engine.

Keep testing - you'll find it.

 

[Beammeupscotty]

Yeah I’ve tried very hard not to make a post on the forums lol this isn’t my first time working on a car but first time diesel car. I’ve done some diesel truck stuff but not much.

Log: https://log.tunezilla.com/s/hHIyKUBd

 

[Beammeupscotty]

C

Group A:

'003

Group B:

'010

Group C:

'011

Engine Speed

Air Mass

Air Mass

EGR Solenoid

Mass Air Flow

Air Pressure

Manifold Pressure

Accel. Pedal Pos.

Engine Speed

Boost

Boost

Charge Pressure

TIME

(G28)

Specified

Actual

(N18)

TIME

(Actual)

(F96) BARO

(Actual) MAP (G71)

Sensor 1 (G79)

TIME

(G28)

Specified

Actual

(N75) Solenoid

Marker

STAMP

/min

mg/str

mg/str

%

STAMP

mg/str

mbar

mbar

%

STAMP

/min

mbar

mbar

%

0.78​

1953​

850​

1060​

4.8​

0.04​

610​

989.4​

1346.4​

37.6​

0.38​

1827​

1887​

1428​

24.7​

1.99​

2394​

850​

985​

4.8​

1.18​

1205​

989.4​

2386.8​

100​

1.58​

2247​

1948.2​

2142​

64.1​

3.19​

2814​

850​

975​

4.8​

2.38​

1025​

989.4​

2111.4​

100​

2.78​

2667​

1948.2​

2121.6​

73.7​

4.39​

3192​

850​

935​

4.8​

3.58​

960​

989.4​

2101.2​

100​

3.98​

3066​

1948.2​

2101.2​

78.9​

5.63​

3570​

850​

895​

4.8​

4.82​

920​

989.4​

2101.2​

100​

5.23​

3465​

1948.2​

2080.8​

84.5​

6.84​

3906​

850​

840​

4.8​

6.04​

880​

989.4​

2040​

100​

6.44​

3801​

1948.2​

2019.6​

88.9​

8.04​

4179​

850​

820​

4.8​

7.24​

850​

989.4​

1999.2​

100​

7.64​

4095​

1927.8​

1989​

92.4​

9.24​

4368​

850​

775​

4.8​

8.44​

825​

989.4​

1978.8​

89.8​

8.84​

4326​

1856.4​

1968.6​

94.4​

10.44​

3318​

425​

665​

4.8​

9.65​

750​

989.4​

1876.8​

51​

10.05​

4368​

1111.8​

1550.4​

51.8​

11.64​

2373​

380​

535​

4.8​

10.84​

655​

989.4​

1550.4​

0​

11.24​

1806​

999.6​

1366.8​

38.6​

Did this getting on the expressway this morning, Couldn't quite get it to redline.

 

[Beammeupscotty]

If you google image search "ALH injector nozzle" you will see where the identifying marks on the nozzle are - they are located on the part of the injector that is held in place by the large cap-nut. Not visible unless you remove the injector and then disassemble.

I had them out and didn't see any identifiers on the nozzles. They are a bosch injector though.

Not hard, but you need to have a new crush washer and keep things very clean. Purists will say the nozzles will need to by properly calibrated for primary and secondary pop-pressure. Many have replaced nozzles themselves with no issue. best to ensure at the very least that you have proper spray pattern and atomisation.

Yeah I've read plenty on that one, I'd prefer to just not bring it into this thread lol

Much debate on which nozzles are best, but most agree that bosch, bosio and firad make decent nozzles. try very hard to ensure you don't get any fakes if you do replace the nozzles.

Yeah I think I've settled on the sprint 520's for what I want from the car, but again later down the road.

even with the cross-hatch, a compression test is a good way to verify things are alright mechanically. If the compression is fine, you can put that to bed and concentrate on investigating other issues.

Agreed, I just need to find time to get it done.

On your commute, I would expect at least 40-45 mpg from that car in proper running order if not more. My passat gets better MPG than your Jetta (it shouldn't) on a 10mi highway commute and occasional longer trips. that's with a much heavier car and a larger 2.0L engine.

Keep testing - you'll find it.

 

[Windex]

If they had no identification, they are not bosch. Genuine Bosch nozzles always have their logo on them like this:

 

[Beammeupscotty]

If they had no identification, they are not bosch. Genuine Bosch nozzles always have their logo on them like this:

No no, The injector body has Bosch stamped into it not the nozzles, the nozzles don't have anything on them. Maybe they're aftermarket? I wish there was a better more precise way of identifying the nozzles.

 

[Windex]

Injector bodies can go through many sets of nozzles. If the nozzles had no branding on them, then they are not the original Bosch nozzles. Likely the injector bodies are Bosch but the nozzles are not.

 

[oilhammer]

If it is visible black smoking it is overfueling. If it is not flagging anything related to MAF or boost, it probably isn't starving for air. Or, at least, there is nothing "wrong" with it on that front. If the EGR is deleted, how? What type of software is in there? TDIs rarely get the EGR tuned away without also having a power adding type of software change, too. Otherwise, on an ALH in the ULSD era, there really is not any good reason to do away with the EGR on an otherwise stock car.

Having had one now for 13 years and over 200k miles, I have become a fan of the MAF delete tune on the ALH. Runs great, excellent driveability, NO smoke at all, good strong power off idle and midrange, and the oil stays clean. Coupled with the 11mm pump, everything else stock (including stock proper tires and the nice lightweight Avus OEM wheels, and all the appropriate undershields) it is always good for a solid 50 MPG when my other ALH, also an 11mm pump but stock software (othwerwise identical) will "only" get about 46 doing the same driving. And my driving is mostly fast (80+) highway speeds, I rev it out to 3.5k+ daily, and routinely wind it up well into triple digit speeds. That's where the MAF delete starts to suffer. It cannot spin much past 4k RPMs, and starts to peeter out around 115. The stock one keeps on pulling right up to the speed limiter.

I think you probably have too aggressive of a tune, too big of nozzles, or a combination of both.

 

[burpod]

maf-delete doesn't suffer at any rpm or speed. my rabbit knows this quite well if it's suffering, something else is limiting it (or the map smoke limiter isn't right) i can plant my foot at 4k+ rpm and it will just rip, it's a little insane....

 

[Beammeupscotty]

Injector bodies can go through many sets of nozzles. If the nozzles had no branding on them, then they are not the original Bosch nozzles. Likely the injector bodies are Bosch but the nozzles are not.

Thank you for the info! I think Burpod is gonna be kind enough to help me out in Identifying them and such! Will keep yall posted.

 

[oilhammer]

MAF delete does effect it, pod, depending on what the fixed value is set to. If it is low, like my RC0 tune, it absolutely runs out of steam at higher RPMs. Unless we are talking about two different things. My MAF value is fixed at 450, never changes. Idle, 3000 RPMs, whatever. Always stays there. But the car runs so well, I don't want to change a thing. If I wanted to go fast, I'd buy a fast car.

 

[burpod]

no, i assure you it doesn't. a maf-delete tune will not run out of steam, ever, if it's done right. it's completely dependent on how the tune is written i've done extensive testing, believe me

 

[Beammeupscotty]

Just an update: Burpod offered to help me get the car correct.

Turns out the switching the Softcoding from Auto to Manual wasn't a good idea for me at least. I didn't even think about the maps being different from auto to manual ( I was under the impression it wouldn't run without the TCU ) and the car was over fueling, but on top of that the injector nozzles were changed by a PO to a bigger size, which we landed on .215's. This would explain why the injection pump was nearly 25mgs at idle and the actuator on the turbo had been adjusted. It took some time to figure out the injectors size but once he determined they were .215's he hooked me up with a base tune and we went to tuning for the car and man when I say this thing is a different animal I mean it. It went from Smoking at any throttle position/load to clean burning quickly. The power and drivability are also sooooooo much better, I can drive the car at any RPM range with ease! If I had known the injector size I think this process would've took a couple of hours to get the car tuned up and running great!

I am very happy with the car now, and I couldn't possibly show enough appreciation to Burpod for taking on the challenge with me to figure the whole mess of a car I had! Now I have 3 different tunes that I can run for different things! Dudes a beast! If you are looking for tuning I highly recommend him, he's extremely helpful and explains things to help you understand what you need to do when you log your car and in the changes he makes!

 

[03TDICommuter]

and I couldn't possibly show enough appreciation to Burpod for taking on the challenge with me to figure the whole mess of a car I had!

Thanks Burpod! Very cool!

 

[Nevada_TDI]

Burpod wrote a new tune for me and I could not be happier; lots of power and no more smoking at WOT!

 

[03TDICommuter]

Burpod wrote a new tune for me and I could not be happier; lots of power and no more smoking at WOT!

Let us know your mileage too when you refill your tank. He's helping me with my Beetle - right now I'm still collecting data.

 

[Nevada_TDI]

This is a fuel related question: I recently replaced my in-tank fuel sender; I used VCDS to get the gauge to read more correctly with my old fuel sender.
My point is; I do not remember how to get to the fuel sender code in VCDS. When full the gauge shows 7/8 of full, how do I fix this? TIA