MPS Differences?, 0280100041 vs 0280100043 Options

[FlacaProductions]

Seeing both part numbers seeming used interchangeably between 1.7 and 2.0's.

Was there a year that a changeover was made or?

[JamesM]

Seeing both part numbers seeming used interchangeably between 1.7 and 2.0's.

Was there a year that a changeover was made or?

041 is a 71-72 1.7 sensor

043 is a mid 73-74 2.0 sensor

Not interchangeable, at least not out of the box without modifications.

There were quite a few different MPS used across the various years and engines in the 914, 5+ different versions for the 1.7s and 4+ different versions for the 2.0s and while they are physically interchangeable and you can usually get a car to start and run with the wrong MPS they will not run correctly unless you have the correct MPS for whatever ECU you are running. The parts all contain different calibrations as well as some internal differences that impact their function as well.

The most common MPS part numbers you will see are

041 72 1.7 sensors
049 73 1.7 sensors

037 early 73 2.0s
043 & 044 73-74 2.0s
052 75+ 2.0s


There is some level of interchangeability with some of the sensors but thats a pretty in depth subject, in general though you dont want to swap any of the 1.7 sensors with any of the 2.0 sensors and you dont want to swap the early 73 2.0 sensor with anything.

[FlacaProductions]

Exactly what I was looking for - thank you!

[914Sixer]

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[FlacaProductions]

I need to look at this closer and try to decipher - is this from PBanders site?

I have an 041 on my 2.0 - a transplant before my time - done by Brad Mayeur.
I need to look at the engine number and also check my MPS to see if the seal has been broken and possibly adapted...

[JamesM]

I need to look at this closer and try to decipher - is this from PBanders site?

I have an 041 on my 2.0 - a transplant before my time - done by Brad Mayeur.
I need to look at the engine number and also check my MPS to see if the seal has been broken and possibly adapted...

The 041 is a little trickier to adapt to 2.0 specs as its an earlier casting of the housing that does not allow the same length of diaphragm travel that the later castings do. You need to machine part of the end housing and add the 2.0 spacer ring, then adjust it to 2.0 specs. You can get one sort of close without these mods but it wont run correctly. As far as converting 1.7 sensors the 049 is an easier place to start as it uses the later housing.

[JamesM]

Click to open

That is only a partial list. This page as a far more comprehensive listing of d-jet MPS

https://jetronic.org/en/d-jetronic/mps

Also if you plan on re-tuning an MPS to a different spec you might not get to far with the information from Brad Anders page. He has correct information however as the MPS themselves are effected by altitude and atmospheric pressure. Adjusting one based on the inductance specs he provides might get you close but as they will vary based on where you are, and just day to day based on air pressure the best way I have found to do it is to basically "clone" the adjustment of a known good sensor on the bench. I used a T'ed vacuum setup and a switch attached to my meter to ensure two sensors are identical across the entire operating range.

[DC_neun_vierzehn]

Wow. Some really good info being shared here. Thank you.

[FlacaProductions]

@JamesM - thank you - great info.
I need to sort my 123 install first. I have great confidence in what Brad did and it ran great before my dizzy vacuum went away but my MPS needs investigation/confirmation...