VP37 Injection Pumps: Parts & Repair

The topic from yesterday is still bothering me and making me a little unsure. In my opinion, the ESP models of type VP37 should be essentially the same. I only know that some very old 1Z models had a minor modification. Is that correct? Does anyone know more about it?

AHF, ASV, ALH, and AGR engines all use the same pump (part number 038 130 107 B).

exception: ALH with automatic transmission.

CU Gremlin.

Hi Gremlin,

And what about the 1Z, AHU, and AFN engines? Can you tell me something about those? Thanks for the answer so far!

1Z and AHU have the same [thing/attribute].
ALE (90 hp) has its own.
AEY (or ADI) has its own...
AFN has its own.

(at least, different VW part numbers)

m;

'But, in my opinion, having different VW part numbers is normal.'
What about the Bosch part number?

Hi,
I also looked into the AFN (Air Flow Needle) for the Golf 3 the other day.
VW Part Number: 028130115A
The Bosch part number identified through the re-identification process is: 0460404986.
Decoding the Bosch part number revealed that, in addition to 028130115A, it also corresponds to the VW part number 028130110P.

And the madness continues. The part number 028130115AX (replacement pump), when decoded, reveals 0986440504. And then, decoded again...

Conclusion:
This pump may have the following model numbers:
VW Part Numbers: 028130110P; 028130115A; 028130110PX (Replacement pump); 028130115AX (Replacement pump).
Bosch part numbers: 0460404986; 0986440504 (replacement pump).

Can someone confirm my findings?

Best, Andy.

Hi Schraber,

Currently sold fuel pump from VW for the 1Z/AHU engine: 028 130 115M ... 0 460 404 994.

The same applies to the AFN: 028 130 115A ... 0 460 404 986.

The AT pumps have different numbers because the refurbishment process does not allow AT and new devices to be labeled with the same number. However, there is no technical difference between the AT part and the new part.

The pumps are different. The reason is that the AFN has a larger injector nozzle diameter to allow more fuel to be injected in a similar injection time (as the 1Z). However, this also means that the pump has to work harder, otherwise the maximum injection pressure will decrease, and the correct atomization of the fuel will no longer be guaranteed.

If a refurbishment company were to take an AFN pump and modify its internal components to meet AHU standards, you would essentially have the housing of an AFN pump but with the functionality of an AHU pump.

If someone were to "accidentally" install an AFN pump on a 1Z engine, I would immediately go to the nearest Bosch service center and get the corresponding injectors. That's the easiest way for me to do any kind of tuning. Anyone who then has the fuel map in the engine control unit adjusted to match that combination is a real wolf in sheep's clothing.

Bertil wrote:

If someone had "accidentally" installed an AFN pump on a 1Z engine, I would quickly go to the nearest Bosch service center and get the corresponding injectors for it. That's the easiest way for me to do any tuning. Anyone who then has the fuel map in the ECU adjusted to match that combination is a real wolf in sheep's clothing.

Hi Bertil,

However, the initial mistake likely won't make the story legal.
Ultimately, the fact is that a diesel engine designed for 90 horsepower is being injected with fuel to produce 110 horsepower, and in my opinion, this ultimately invalidates the vehicle's operating permit.

Whether and when it will be noticed by official bodies is, of course, another matter...