MAP sensor MOD...

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
I'm very interested in make this mod and i believe that a lot of members of this forum too...who know!
I don't understand at all the information of other threads...

Material needed:
-3.3V Zener diode
-1K Potenciometer
MAP sensor wires:
Pin1: signal ground
Pin2: temperature output voltage
Pin3: 5V supply and reference voltage
Pin4: Pressure output voltage

in wich MAP sensor pin i must to install Zener diode?
Potenciometer must be connected to ground.... to MAP sensor ground(Pin1) or chassis ground?

Wich is the correct Ohm resistance? 100Ohm?

I suppose that boost is adjusted with potenciometer... A bigger value that 100Ohm is more or less boost? Thanks in advance..:)
 
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93FryGuy

Veteran Member
Joined
Mar 2, 2008
Location
Northwestern OH
TDI
1998 Jetta w/ the 1Z
What's ve?

From what I read here the number 4 pin is what you want.
Then connect the zener diode with the negetive end to the #4 pin, then to a potentionmeter you can control, then to chassis ground. I think I have finally made sense of it for THAT car.

But that was on a different TDI engine than either of ours, so I am not sure how it works on our. I dont think we even have a MAP sensor, but then again, you are in Spain, I am in US, so dunno the differences are, its so confusing sometimes.....

On the page you got that diagram from, he said is is possible to do it with the controls I have, and I am trying to find out how this is possible, need to look around somemore, OR anyone here be kind enough to explain how this is done to a 1998 1Z TDI?
 

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
Wich is the approx value resistance for 1.3bar from stock map?
 
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mctdi

Veteran Member
Joined
Dec 10, 2004
Location
se WI
TDI
2010 Jetta
milehighassassin said:
Should this be the same for a PD?
This might work on PD. :confused: But having played with bad wires to the turbo vane position sensor, only on the PDs, and seeing the requested and actual MAP & MAF values both before and after repairs; I think not likely. :(

As the turbo vane position sensor seems to have more input [ control ] on the running boost pressure then the MAP sensor does.

Without the turbo vane position sensor connected [ working ] actual MAP was always running about 10 PSI at cruse. This while requested MAP might be say 6 PSI. If pressure spiked to something above 13 PSI, then it was reduced, so there was still some pressure control.

With the turbo vane position sensor connected the actual MAP was always close to the requested MAP. And the same for the MAF.

Maybe Jeff-RC, or some other chipper, could add some solid insight on this matter.;) As I would like to know if the turbo vane position sensor does have more input to actual boost pressure than the MAP sensor?
 

andypandy

Well-known member
Joined
Aug 10, 2006
Location
Sweden Gothenburg
TDI
Golf MK4 -00 110hp++
hakansson said:
I have no zenerdiod I have only 20Kohm and that give me 1,35 bar.
Ill think this will be great together with bigger nozzles, with this you move the whole map uppwards... as you do with nozzles.
But ill think this will work quite good for all.
Maybe im overworked the mod a bit.
 

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
WOW! i installed it this morning... i installed one 3.3V zener diode and 100Ohm resistor... my boost is 1.7-2.0 bar!!! INNACEPTABLE!
I have MAF mod too... can the MAF mod to increase boost? for to obtain less boost is needed more or less that 100Ohm?
 

Rub87

Top Post Dawg
Joined
Dec 10, 2006
Location
Belgium
TDI
Ibiza '99 90HP
Dude, really.. this mod sucks ass..

When you want to do it right, use diagram that looks like the on I posted here somewhere, use an opamp..
 

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
Please guy, can you explain a bit this diagram? What's a 1/2 LM158? Wich's the Zener value and how connect it? where goes the arrow in the low-left part of picture?
 
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Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
hakansson said:
I have no zenerdiod I have only 20Kohm and that give me 1,35 bar.
have you installed a 20K Ohm resistor only? say that gives you 1,35bar...wich is your stock boost?
 

mctdi

Veteran Member
Joined
Dec 10, 2004
Location
se WI
TDI
2010 Jetta
Satiro said:
Please guy, can you explain a bit this diagram? What's a 1/2 LM158? Wich's the Zener value and how connect it? where goes the arrow in the low-left part of picture?
A "LM158" is an IC chip that has two summing amplifiers in it. This circuit only uses one amplifier, so one half [1/2 ].

The arrow is the center tap, or wiper of a 10k ohm potentiometer, variable resister.

As to the Zener Diode, the circuit looks to be missing that information.

I hope his is of some help.
 

Rub87

Top Post Dawg
Joined
Dec 10, 2006
Location
Belgium
TDI
Ibiza '99 90HP
You use a zener as an resistor to create a stable reference voltage..

12v--> zener --> resistor
Now you have a stable voltage, as much as the zener voltage between de zener and the resistor.. Remebet this diagram I gave for using the 3 bar map man reducing the boost..

If look at the internet and use common sense you will soon find a diagram that you can use to raise boost with a 2.5bar map sensor..

The easiest way is just to use a Ge diode in series with the signal wire..

If you use the "differential amplefier"basic opamp circuit you will be able to regulate boost easy and accurate..
 

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
I installed a zener 3.3v diode and 1k pot... first adjust of pot gave me 1.6-1.7bar... i turned pot a bit and give me 1.3-1.4 bar sustained...:)

Now... when i turn on evry mod have some boost spikes, i have one boost-valve but i can't to adjust it correctly...
I use an air compressor, adjust pressure to 1.5bar in compressor gauge,connect boostvalve and adjust it for to be closed at 1.4 and start to open at 1.5... install boostvalve in engine again and drive for test... 0,6bar sustained! :mad:
wich is the method for to adjust a boostvalve?
 

bencarr23

Veteran Member
Joined
Dec 28, 2004
Location
Waco Tx.
TDI
Golf 2013 white
I have a TPC from www.dieseltunig.ca which does this. and it really does work i used it to rais my boost when i couldnt get jeff to. and the vane position sensor does just that. read reads vane position and conrtols nothing. the ecu always goes off the map that is the only sensor that reads pressure.
 

mctdi

Veteran Member
Joined
Dec 10, 2004
Location
se WI
TDI
2010 Jetta
bencarr23 said:
I have a TPC from www.dieseltunig.ca which does this. and it really does work i used it to rais my boost when i couldnt get jeff to. and the vane position sensor does just that. read reads vane position and conrtols nothing. the ecu always goes off the map that is the only sensor that reads pressure.
I don't know, the turbo vane position sensor seemed to have a big effect on my car when the wires were bad and no CEL. Now fixed, the actual boost follows the requested pressure very tight and changes with going up & down hills.

From post #12 @ http://forums.tdiclub.com/showthread.php?t=202923

"G500 with bad wires
I hope this info is of help to others.

Now looking back, wires were giving a problem about a year ago, without any code. Boost gauge would go to about 10 PSI for cruising on the highway, not change much going up & down small hills. Then a month ago had code P2564 twice.

Code was gone until last week, now code was at every start of engine. From Vag-Com EGR duty cycle was solid 100.6%; actual MAF was well above requested; actual MAP was above requested. So last Sunday went under car and looked around. Found the two wires with wear/ cut. Pulled back the plastic protective sleeve and found the bad yellow wire.

Ordered repair wires and new connector. Fixed wiring, and now EGR duty cycle ranges mostly from 60% to 90%, actual MAF is very close to requested; actual MAP is also very close to requested. The car has more zoom zoom, too. And maybe a little bit better mileage."
 

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
I drove this night a bit and tested mod... i haven't 1.4bar, i have 1.1-1.2 sustained in higher rpms, and i can to reach 1.3-1.4 if i push hard pedal in second-third gear... car is a rocket from 3 to 5 gears with this mod and EVRY...i have installed 3.3v zener diode and 1k pot...
is possible to adjust boost with 1K pot? turning it to more or less resistance? i had 1.6-1.7bar with 3.3v zener diode and 100 Ohm resistor, too much for my turbo...
I will try to adjust boost with pot... i don't want to blow anything!:D
 
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Satiro

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Spain
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IBIZA 1.9TDI 110hp AFN 1998
when the ECU is fooled to think there isn't sufficient boost... what the ECU do for to create more boost? change IQ? if yes, this mod isn't compatible with EVRY mod,isn't?
i have installed a 1K POT and it's difficult to adjust boost, easily have 1.7-1.9 bar of boost!

I have installed for the fuel system 0,210 nozzles and EVRY(1.8-2.0 IQ)...wich do you think that is the suggested boost? 1.2-1.3?
 

Rub87

Top Post Dawg
Joined
Dec 10, 2006
Location
Belgium
TDI
Ibiza '99 90HP
Ehm,

the only thing the ecu does when there isn't sufficient boost is going in limp mode..
 

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
Rub87 said:
Ehm,

the only thing the ecu does when there isn't sufficient boost is going in limp mode..
No, i'm talking about this mod... putting a resistor fool the ecu to think there isn't sufficient boost... what the ecu do for create more boost? increase IQ?
 

zorgman

Well-known member
Joined
Feb 28, 2008
Location
sunderland uk
TDI
vw 1.9 tdi 110 afn
just done the map mod but only used a 4.3v zenner as my map kept throwing fault code up, dont know why changed the lot all pipes etc but still there now with this mod at long last no limp mode.
done the maf mod as well using a in4148 diode which gives me 4.3v on the output car now revs to red line first time in 3 months.
all ive got to do now is install bigger injectors but confused what to use on my 99 sharan 1.9tdi 110 afn engine, any thoughts on that one please
 

Rub87

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Joined
Dec 10, 2006
Location
Belgium
TDI
Ibiza '99 90HP
Satiro said:
No, i'm talking about this mod... putting a resistor fool the ecu to think there isn't sufficient boost... what the ecu do for create more boost? increase IQ?
As I said..

It will go in limp mode when actual map is too low..

I will do nothing with IQ or whatsoeve..
 

Satiro

Veteran Member
Joined
Aug 3, 2006
Location
Spain
TDI
IBIZA 1.9TDI 110hp AFN 1998
Rub87 said:
As I said..

It will go in limp mode when actual map is too low..

I will do nothing with IQ or whatsoeve..
Soory man for confusion...my damn english.
I make the question by other way:
when i installed a 100 Ohm resistor my boost sustained was 1.8-1.9bar... what the ecu do for to make this boost increase?
 

Rub87

Top Post Dawg
Joined
Dec 10, 2006
Location
Belgium
TDI
Ibiza '99 90HP
Ah, it waited until it had that boost before increasing the N75 duty cycle to taper off boost..
 

belinassu

Member
Joined
Sep 1, 2005
Location
Italy
TDI
Lupo 1.4TDI 2k black
I cut the +5v wire and put a 39ohm resistor between two ends,
this attenuate the MAP supply ancd so attenuate the pressure signal output...

my tdi turbo is more responsive and the boost stronger now ;)

i have not a boost gauge, but boost shuold raise up to 1.3-1.4bar now

hi
Andrea
 

Rub87

Top Post Dawg
Joined
Dec 10, 2006
Location
Belgium
TDI
Ibiza '99 90HP
dude, really, if you want to do things cheap, use a diode, not a resistor, power consumption etc very with temp, this not a stable solution, just put a diode in series with the signal wire..
 

belinassu

Member
Joined
Sep 1, 2005
Location
Italy
TDI
Lupo 1.4TDI 2k black
i wanted to use a diode, but the voltage dropout of 0,3-0,5 volt
seemd to me too much...

why not a diode in series with +5v?
 

Rub87

Top Post Dawg
Joined
Dec 10, 2006
Location
Belgium
TDI
Ibiza '99 90HP
Because the sensor is made to work with +5v and not 4.3v..

a Ge diiode gives 1.2 bar sustained.. and still is capable of triggering limp mode when something goes wrong..

when you use a Si diode, you will see 1.25~1.3 bar, when using a zener in forward position (so not using the Zener effect) you will see 1.35 bar..

I tried it all ;)
 
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