msII v3 4agte

Toyota, Lexus.
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craigs85gts
MegaSquirt Newbie
Posts: 1
Joined: Fri Feb 15, 2008 5:01 pm

msII v3 4agte

Post by craigs85gts »

im having a confusing time building my msII
maybe some people here will be able to help me
out with more accuracy.
i am at this step:


54. Install and solder R4 and R7 {2.49KXBK-ND, 2.49K, red-yellow-white-brown-brown). These are the temperature sensor "bias" resistors. They install above the "&" in the copyright notice.


If you want to use other sensors, you can either:

change the transfer-function files in the MegaSquirt® 68HC908 processor by using EasyTherm to change MegaSquirt's code to match your temperature sensors), or with MegaSquirt-II you 'recalibrate' the sensor table in MegaTune under 'Tools/Calibrate Thermistor Tables...', OR
switch these bias resistors, which may be easier in some cases.
Normally, you should use EasyTherm (with MS-I), it's generally more accurate, as the curve is based on three points, rather than the one point of a resistor swap.


Sensor
Makes
Resistor (ohms)

AC Delco/GM
Daewoo, Buick, Cadillac, Chevrolet, Oldsmobile, Pontiac, GMC
2.49K

Ford
Ford, Lincoln, Mercury
27K

Bosch and
Nippon Denso
Acura, Audi, BMW, Honda, Infiniti,
Jaguar, Kia, Lexus, Mazda, Mitsubishi,
Nissan, Suzuki, Toyota, Volkswagen, Volvo (96-up)
2.2K

Mopar
Chrysler, Dodge, Plymouth
9.31K

i have installed and tested but what are they talking about with easytherm. and what about these resisters for certain cars.
i bought my msII from diyauto.com is it already setup for something.
2nd... the o2 pot is not working. i go to the "tools/calibrate AFR table"
and select narrowband and still nothing. anyone run into the same problem. am i doing something wrong...do i have to setup the EGO
correction parameters first.


55. Time for a little testing. Install the processor, hook up the stimulator, hook up the DB-9 to the board and PC, fire up MegaTune, and bring up the "Realtime Display" window. You should be able to see responses when you move the knobs on the stimulator.

First, look at the RPM - it should change when you move the RPM pots on the stimulator. Note that if you have installed the VR input circuit jumpers in step #52, the stim is not currently designed to put out the sort of signal (AC) the VR circuit expects. However, by adjusting the pots at R52 and R56, you might be able to get a useable signal into MegaSquirt. The RPM may not be stable at each end of 1000-6500 range, but it should be workable over that range, at least. Then you'll know that the rpm input circuit is functioning at it should.

All sensors should react to the corresponding pots on the stimulator. Before doing anything else, go to 'Tools/Calibrate AFR table' and select your sensor. Then when the O2 pot is moved, the O2 voltage moves irrespective of the other settings. On the other hand, the EGO correction bar (or equivalent gauge on the tuning screen) WILL NOT move away from 100% unless you have the EGO correction parameters set properly and MegaSquirt senses the proper inputs to activate EGO correction. Note that if you have not connected a TPS to your MegaSquirt® EFI Controller, (testing in car, for example) the TPS value will slowly creep up to a maximum value, and O2 correction will be disabled. You should check that MegaTune reads approximately the correct barometric pressure when no vacuum is applied. Below is a chart of the 'normal' barometric pressures for various elevations above sea level. MegaSquirt® should generally be within 4 or 5 kPa of the values below at your elevation.

Barometric Pressure vs. Elevation
Elevation Above Sea Level
Atmospheric Pressure

Feet
Meters
kiloPascals
(kPa)

0
0
101.33

500
150
99.5

1000
300
97.6

1500
450
95.9

2000
600
94.2

2500
760
92.5

3000
920
90.8

3500
1070
89.2

4000
1200
87.5

4500
1400
85.9

5000
1500
84.3

6000
1800
81.2
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