Turbo tuning; Golf III TDI with automatic transmission

Hello, dear Diesel community,

I'd like to share some thoughts and hear your opinions on the matter.
Please don't get upset because it's about jet tuning again!!!

Not that I'm not satisfied with the performance; the Golf runs well, according to the speedometer, 190.
But out of a desire to experiment (if it won't cost too much), I would like to try out some jet tuning.

I have a G3 TDI with an automatic transmission and the following specifications:

Release date: April / 1997.
Engine code: AHU, 90 horsepower.
MSG: 028906021GG 1.9l R4 EDC 00AG 1432, coding 0001.
Transmission: 01M927733DA AG4 01M, coding 0000.
ESP: 028 130 110 H (which indicates an 11mm pump).
Nozzles: should be 0.158 (I haven't checked yet).


Since engine tuning for automatic vehicles offers a different starting point and approach, I wanted to learn more about it.
There's already plenty of information in our forum about injector tuning for TDI engines with SG (Selective Catalytic Reduction) systems. The reports regarding different nozzles and their effects on the transmission and clutch are also fairly consistent.

The experience with jet tuning using AG (presumably a specific technology or method) is less common, which means that many questions could not be answered.
First, I used the search function to find all the posts from Gremlin and garth.brooks (both of whom are automatic drivers) and read through them for a few days. In addition, I contacted garth.brooks via private message and asked for his experience, and I would like to thank him again at this point.

His AG4-01N seems to be handling the increased power well and isn't causing any problems. At least, there's no significant risk of the transmission failing immediately. As long as you don't go overboard with the extra power, everything should be fine.

Given that I have a 11 mm pump and 0.158 injectors, the standard 0.184 injectors (found in 1Z, AHU, or ALH engines) would be perfectly sufficient for me. And I'm sure each of you has plenty of those little nozzles lying around.

First question: Is the engine already experiencing idle problems?

Secondly, is the soot limit already being reached, requiring an increase in boost pressure?

And thirdly, how much does a used but good set of 184 nozzles cost me?


Best regards, Georg.

First question: Is the engine already experiencing idle problems?

Secondly, is the soot limit already being reached, requiring the boost pressure to be increased?


No and no.

CU Gremlin.

I would, if anything, take at least the 205 model from AFN.
And without any further modifications, it's definitely useless because you won't notice any increase in performance otherwise.
Okay, so we're talking about performance tuning, specifically in the context of a piggyback module or chip (possibly a 10c tuning).

Are you absolutely sure that the AHU (Air Handling Unit) has smaller nozzles?
To the best of my knowledge, he also has the 184 model.

The ALH automatic transmission has the 158 model.

I can't recall different nozzles in the FILE - and as a 1Z mechanic, I look at it every day .

m;

@Steffarn:
So far, the prevailing opinion in this forum is that even pure "tuning" (adjusting engine parameters) can improve performance. Ulf has also objectively proven this using a dynamometer. Of course, the effect is much greater with further modifications, but, as you say, "it's just for show" - pure tuning probably isn't.

@Georg:
The problem with used injectors is always the spray pattern and the previous mileage. You probably won't be able to check this with most suppliers. And then you'll be surprised that yours runs unevenly, has little extra power, smokes, or, in the worst case, a piston burns out. Therefore, I would only install used injectors after checking the spray pattern or if they definitely have very low mileage. But of course, that's up to you. You should be able to get a new set for around 400 euros. I wouldn't spend more than 100 on a used one, and even then, only if I'm sure everything is okay.

Regards,
Guste.

Good morning, everyone,

Thank you for the quick and helpful answers.


Gremlin@:
Are you speaking from experience? In your reports, I haven't found any mention of you having equipped your ALH automatic transmission with larger injectors.

Steffarn@:
I understand that when doing a proper tuning with larger injectors (e.g., 205 or 216), other stronger engine components, such as the turbocharger, a larger intercooler, etc., are also required. That's where you can expect a significant increase in power. However, for me, it's not about a large power gain, but rather the responsiveness in the higher RPM range. Mine feels quite sluggish at higher RPMs, and I suspect it's due to the smaller injectors. And a power increase of 5-8 horsepower would also be sufficient for me.

dieselmartin@:
No, I'm not sure if my AHU automatic has 158 injectors, but according to other statements in this forum, it should. Since I have an 11mm pump, I would also need smaller injectors to achieve 90 horsepower. Since you have access to the documents, I would appreciate it if you could review them, if possible.

Guste100@:
Okay, I absolutely agree. If we're using used nozzles, then they should definitely have low mileage. Sure, but who guarantees that?
Currently, I only have 130,000 kilometers on the odometer, and my injectors are still in perfect condition; there's no excessive smoke, rough idling, etc.
However, if I find myself needing to replace my nozzles after 30,000 to 40,000 kilometers, then the question arises: If I'm replacing them, maybe I should consider larger ones...
And for these purposes, I posted this topic in the thread.

Thank you, further opinions are always welcome!

Best regards, Georg.

Hi,

@guste100
What happens if you only replace the nozzle tip/injector nozzle of used fuel injectors?
'Head swapped? Assuming the opening pressure is still correct.' Here are a few...
Save money. Or is the nozzle always worn out as a complete unit?

Yes, it's definitely possible, but it's not easy to obtain nozzles on their own. Furthermore, you will need to have the opening pressure adjusted afterwards.

There should also be Bosch service centers that can install different nozzles and replace everything else that is necessary for 80€ per piece.
This has been discussed several times before.

Hello everyone.

The nozzles are available individually!

AXG: 2437010126
AHY: 2437010060
AHF: 2437010077

According to the Bosch online catalog, the price is 45 euros per piece!
That makes changing the nozzles worthwhile again, especially if you also have the opening pressure checked!
Or who would just replace an entire injector unit, costing 175 euros each, times three, plus an unnecessary NBF (Nozzle Balance Factor) check!

But that's exactly my problem; I previously thought the only difference between the nozzle bodies of the AXG and the AHY would be the opening pressure.
That's not the case, I suspect that the individual holes are flow-optimized and adapted to each specific engine!
Does anyone know the differences?
These are also the reasons that prevent me from simply replacing the original nozzles with the larger ones. There are still too many uncertainties; I can't afford to risk damaging the engine!

Best regards, Ferdi.

@ Georg

Do you know how ESP works?

I think your conclusion that a 11mm piston implies smaller nozzles is incorrect. I can also inject a small amount with a large injector; I don't need to artificially restrict the nozzles for that.

Does AKTE not know your pump number?!

The injectors in the Golf 3 are NEVER different depending on whether it's a manual or automatic transmission.

The G4 engines are quite different from each other.

"Especially, models 1Z and AHU have the same [feature/part]."

I got 184 in the 1Z, so you also have 184 in the AHU .



So, ultimately, your only options are to either increase the cross-sectional area and/or the opening pressure.

AFN 190 bar 205 um.
ASV 220 bar 205 um.
AXG 220 bar (??) 216 um

m;

Hi Martin,

I am very well aware of how ESP works; that's not the topic here.

And my conclusion that a 11mm pump can inject more fuel compared to a 10mm pump is also correct. This has been proven multiple times through various reports and opinions. The principle is simple: a higher pressure (caused by the larger pump) allows for more fuel to be injected in the same amount of time, given the same nozzle diameter. Therefore, I probably need smaller injectors to achieve 90 horsepower (assuming I actually have a 11mm pump).

I haven't been able to find any confirmation reports specifically for AHU automatic transmissions, only for ALH automatic transmissions. I will therefore have to continue to make an effort...

When I was at the mechanic's shop regarding a leak in my ESP system (due to 4 years of biodiesel use), he confirmed that I have a 11mm pump because of the automatic transmission combination, and therefore, you can't simply install any pump from a 1Z or AHU engine. I didn't ask him about it back then because of the nozzles.

The ALH model with automatic transmission uses a combination of 158 injectors and an 11mm pump. It's a direct successor to the AHU model, but already complies with EURO 3 emissions standards. Perhaps that's the catch?


So, more specialized knowledge is required!
I don't want to have to remove the nozzles just to find out that they are the 0.158 or 0.184 size nozzles.

Best regards, Georg.

Please provide the Bosch ESP type plate information here.

Then it will be clear which pump is installed and what the diameter of the piston is.

The cylinder bore diameter, among other things, is listed on the nameplate.

Best regards, Rainer.

Here's everything that's on my ESP:

0 460 404 685
510-161 015
028 130 110 H
79847B

Disclaimer: Information provided without guarantee (not everything is 100% visible).

The Bosch online catalog doesn't really help me understand things any better.
He knows nothing other than 028 130 110 H.

I hope you can make sense of this.

Georg.

There must be something with "VE4" printed on it somewhere.

Hi Georg,

I didn't mean to be rude with the "pump" comment; I just didn't want to tell you something you already know, or talk to you in technical jargon that you might not understand.

I'm not sure that a 11mm piston generates more pressure.

He can deliver more volume with the same impeller, but for that, he also needs more power on the timing belt - assuming the impellers are the same, that there is an unlimited amount of power available for the timing belt, and that the compressibility of the diesel is neglected, HE CAN build up more pressure.

In other words, the pump CAN deliver more output if the same nozzles are used.

These are already three unacceptable assumptions and one subjunctive clause, so I don't believe that an 11-liter pump *always* necessitates 158 injectors.

For the 90 horsepower, the injection time is simply shortened – and that's how you also end up with only 35.2 mg/H (torque limit), just like me.

"The process of increasing fuel injection pressure using larger injectors only works because the engine control unit (ECU) is unaware of the modification and is attempting to compensate for compression losses in the diesel fuel (!!!), which are less pronounced with larger injectors."

Your pump should have some markings that indicate its type, likely a Bosch code, which would tell you what components are installed.

Oops, Rainer was faster.

Do you have a number like that?

m;

Rainer K. wrote:

There needs to be something with "VE4" on it somewhere.

The Bosch Ecat system identifies this part as 028 130 110 H, which corresponds to VE4/10E2250R510-3.

Could someone please tell me what conclusions can be drawn from these numbers?

Does VE4/10E refer to a 4-cylinder engine with a 10mm piston? Do you have any more ideas about what the rest means?

Regards,
Guste.