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redflagmaclo
I’m wondering if anyone has reccomendations on how to splice/add a variable resistance potentiometer in the main electric line from the manifold pressure unit to the ECU.. I’m going to be spending a lot of time in the Santa Fe/Los Alamos NM area which covers 5000’ to 7800’ elevations. I need the ability to lean the mixture as I travel from 1000’ MSL to over 8000’. My son and grandkids live there and I can now spend quality time with them and I make 2 visits a year from NC. I’m the original owner of a ‘74 2 liter and have just become a member of this group. Wish I had joined a long time ago.
TheCabinetmaker
I've driven all over that area. Never had any problems with my djet.
brant
unless your running a wide band AFR read out.
not sure I'd mess with the mixture
the system self adjusts somewhat for altitude already
and the risk of damage from turning it lean... by the seat of your pants... would worry me.

the motors like to run lean... feel good when they are lean... right up to the point that damage occurs.
StarBear
Wow, another original owner! That makes maybe 7-8 of us.
Welcome aboard! biggrin.gif
JeffBowlsby
D-Jet automatically adjusts for differences in atmospheric pressure. One of the great things about D-Jet.

The MPS mechanically compares intake air manifold pressure to atmospheric pressure to determine its sensor output value (inductance) which is delivered to the ECU as a factor in determining the fuel injection pulse width.
mgphoto
You could add a potentiometer to the head temp sensor but you would need an AFR meter to track fuel ratios to prevent the engine from damage running lean, as stated the MPS is well suited to compensate for changes in altitude.
914sgofast2
QUOTE(JeffBowlsby @ Jun 2 2022, 02:49 PM) *

D-Jet automatically adjusts for differences in atmospheric pressure. One of the great things about D-Jet.

The MPS mechanically compares intake air manifold pressure to atmospheric pressure to determine its sensor output value (inductance) which is delivered to the ECU as a factor in determining the fuel injection pulse width.

WOW! That’s great to know. So if I drive up to Lake Tahoe from Sacramento then my 1.7L should make it?
mgphoto
QUOTE(914sgofast2 @ Jun 2 2022, 07:19 PM) *

QUOTE(JeffBowlsby @ Jun 2 2022, 02:49 PM) *

D-Jet automatically adjusts for differences in atmospheric pressure. One of the great things about D-Jet.

The MPS mechanically compares intake air manifold pressure to atmospheric pressure to determine its sensor output value (inductance) which is delivered to the ECU as a factor in determining the fuel injection pulse width.

WOW! That’s great to know. So if I drive up to Lake Tahoe from Sacramento then my 1.7L should make it?

Not a problem, it was built to do just that.
TheCabinetmaker
QUOTE(StarBear @ Jun 2 2022, 03:06 PM) *

Wow, another original owner! That makes maybe 7-8 of us.
Welcome aboard! biggrin.gif

Owner since 73!
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