VTEC- How to hook it up

[FMYStreetRacer]

Vtec info. Please read all of the threads as there is more info updated regularly.
Dog
-------------------------------------
p30_obd1
A1 BRN INJ1 INJ1
A2 YEL INJ4 INJ4
A3 RED INJ2 INJ2
A4 ORN/WHT VTS VTEC solenoid
A5 LT BLU INJ3 INJ3
A6 ORN/BLK PO2SHTC O2 sensor (heating element)
A7 GRN/YEL FLR1 fuel pump
A8 (empty)
A9 GRN/WHT IACV IAC valve
A10 (empty)
A11 (empty)
A12 YEL/GRN FANC Fan Output
A13 GRN/ORN MIL MIL (check engine light)
A14 (empty)
A15 BLK/RED ACC (a/c compressor clutch)
A16 WHT/YEL ALT C alternator
A17
A18 (empty)
A19 (a/t trans only)
A20 RED PCS EVAP purge control solenoid
A21 RED/GRN ICM ICM
A22 (empty)
A23 BLK PG1 ground
A24 BLK PG2 ground
A25 YEL/BLK IGP2 to main relay and to gound for o
A26 BRN/BLK LG1 gound
B1 YEL/BLK IGP2 to pin A25
B2 BRN/BLK LG2 ground to shields for CYP & TDC
B3 (a/t trans only)
B4 (a/t trans only)
B5 BLU/RED ACS a/c switch
B6 (empty)
B7 (a/t trans only)
B8 BRN/RED PSPSW PSP switch
B9 BLU/WHT clutch interlock switch
B10 YEL/BLU VSS vehicle speed sensor
B11 ORN CYP P CYP -P
B12 WHT CYP M CYP -M
B13 ORN/BLU TDC P TDC -P
B14 WHT/BLU TDC M TDC -M
B15 BLU/GRN CKP P CKP -P
B16 BLU/YEL CKP M CKP -M
D1 WHT/BLU VBU Back Up Power
D2 GRN/WHT BKSW brake switch
D3 KS Knock Sensor
D4 BRN SCS service check connector
D5 (empty)
D6 ORN/BLU VTM VTEC pressure switch
D7 LT BLU TXD/RXD (data link connector)
D8 (empty)
D9 PNK ALT F alternator
D10 GRN/RED ELD electric load detector
D11 RED/BLU TPS TPS Signal
D12 YEL/GRN
D13 RED/WHT ECT ECT sensor
D14 WHT PHO2S O2 sensor
D15 RED/YEL IAT IAT sensor
D16 WHT/YEL VREF VREF
D17 WHT MAP Map Signal
D18 (a/t trans only)
D19 YEL/GRN VCC1 MAP 5V
D20 YEL/WHT VCC2 TPS 5V
D21 GRN/BLU SG1 MAP GND
D22 GRN/WHT SG2 TPS GND

[FMYStreetRacer]

this might help to. it's from apexi and it's the pinouts to hook up a v-afc to a 92-95 civic.

[Jstue]

also some one gave me this to look at http://www.hondaswap.com/articles/viewer.php?id=17

[FMYStreetRacer]

green is the oil pressure. one wire goes to ground (there is a ground location at the t-stat) and the other get's wired up to the ecu.

oh yeah and that link looks like it has good info. wire it up and go! it's super easy, just don't think it's too hard and it won't be.

[Jstue]

just to re asure myself so i dont blow somthing up :lol:...

the green wire goes to the vtec oil pressure port on the ecu.
the grey wire goes to the t-stat and and to the same vtec port as the ecu?
or is it jsut to the t-stat.

and.. where is the t-stat located :?

thanks so mutch for your help almost vtec time!

[S Q A D]

this post rocks !!

[FMYStreetRacer]

do you have a check engine light on? also what kinda of intake do you have? i have a metal short ram and the vtec is really loud. floor it in 1st and listen around 4800 rpms.

[makku]

excellent post! now I know what to do for my new p28. Thanks!

[Jstue]

i dont have an intake, due to boost plans, isint there some way you can hook up a vtec light? or is there an eazyer way.

[FMYStreetRacer]

yeah you can hook up a led light. one side to vtec signal wire and the other to a ground location.

[DOG]

Excellent thread and info you guy's. 8)

[seano]

Excellent thread and info you guy's. 8)

seriously.:yum:

peaces.

[FMYStreetRacer]

Excellent thread and info you guy's. 8)

thanks. i had to search allot around when i was planning on doing my mini me with a p08.

[98DoHcKiller]

Or if you want you can get an MSD RPM switch from summit racing or a Apex AVC thats what i have i have a y7 with the mini me y8 and i have the avc it works pretty good

[pointcheck]

Hey folks i bought an OBD0 to OBD1 harness for my D15B Vtec swap. It says to hook up the vtec solenoid to A4, and the oil pressure switch to D6. So far so good. It says to hook up IAB solenoid to A17 and Knock sensor to D3. Where is the knock sensor and the IAB sensor on the engine?????

[soccaian]

for this being so easy, i still cant get my VTEC oil Pressure sensor CEL to go away... i grounded one wire to the throttle body, and the other runs to the correct spot on the ecu... any ideas on what could be the problem?

[DOG]

OBD I ECU Anatomy
Thanks to Hondata
www.hondata.com

Introduction

The Honda ECU, like your Honda engine, is a very well designed piece of equipment made to work in many cars under many varying conditions of temperature and altitude. This tech article looks at the functions of the ECU and how it differs from some of the piggyback and standalone systems available.
Backup Microprocessor

The backup microprocessor monitors the function of the main microprocessor, ROM and sensors. In the event of a serious failure it takes over the running of the computer in what is called limp home mode. In this mode the ECU needs only two sensors to run. TDC (top dead center from the distributor) and TPS (throttle position). In fact you can remove entirely the ROM and primary microprocessor and your Honda will still run. Limp home mode is rev limited to 3500 RPM with a fixed ignition and rather rich fuel setting with the engine check light permanently on.

This is military specification redundancy designed to keep you going even in the event of multiple sensor failures. No other vehicle maker we are aware of uses a backup processor and this level of redundancy.
Analog Input

This is where the 12V signals are conditioned and converted into 5V for processing - such as the distributor signals TPS and MAP.
Analog Output: Injector driver transistors

These are excellent quality transistors, which make a substantial contribution to how the well the Honda ECU drives injectors. These transistors do not even get warm (except when low impedance resistors are incorrectly wired in without the Honda resistor box!). All Honda ECUs drive high impedance injectors or low impedance injectors with an external resistor box.

Hondas switch the injectors on and off rapidly (red line). With poorer quality transistors the injectors do not open or close as quickly, resulting in less fuel delivered in the same amount of time. The difference is most noticeable at small injector durations - part throttle.

Increase your fuel pressure and the extra fuel line pressure can slow the injector opening. Another reason to keep low fuel pressures.

Larger injectors with a heavier pintle also take longer to open and close due to inertia and show a similar effect.

We have found Honda ECUs work particularly well with larger injectors. For example one Hondata customer using 830 cc injectors in a B20 turbo has drivability indistinguishable from stock and achieves 30mpg.
Barometric Air Pressure sensor

This sensor tells the ECU at what altitude you are running. The ECU uses this information to make small fuelling adjustments at altitude. This is one of the reasons for Honda excellent idle and part throttle characteristics in all conditions.
Interpolation



Interpolation is the process the computer goes through to calculate the fuel and ignition values between the marked points on the fuel and ignition map. For example, what fuel value should be used at 800 RPM at 400 mb of air pressure? The mathematics are the same for the Honda or any standalone, but there can be differences on how the ECU turns that number into an injector opening time.

The Honda (red line) times the injector opening and closing time to an accuracy of about a millionth of a second, which on a 1ms pulse width is an accuracy of 0.1 % e.g., 96.1, 96.2 ...165.9, 166. Many standalone systems (black line in the diagram above) step the injectors as little as 8 or 16 times - 96, 100, 104 ... 162, 166. This step is probably the result of digital to analog conversion.

There are two schools of thought on this.

* The first is that the differences between the two are too small to be significant.
* The second is that Honda must do this for a reason.

Fuel injection specialists support the second school of thought saying that Honda's precise injector control contributes to driveability compared to some standalone systems with a stepped output for injector duration.
Fuel and ignition maps

VTEC Honda ECUS have two complete and independant fuel and ignition maps for each camshaft. We are not aware of any standalone that has this capability.

Having 2 maps makes the tuning process very straight forward.

* Set the VTEC point to 7000 RPM and tune the low speed cam fuelling and ignition
* Set the VTEC point to 3000 RPM and tune the high speed cam camshaft.
* Plot the torque curves and set the VTEC point to the crossover RPM

This method ensures a very smooth VTEC transition (some JR customers have complained their VTEC was not working when it in fact was)

Be aware that stock Honda ECUs have 10 VTEC points, not one, and at light throttle the VTEC point can be 1000-1500 RPM higher than at full throttle. If you are running with a standalone with one ignition and fuel map and have a variable VTEC point (or a piggyback with a fixed VTEC point), then you cannot have the correct fuelling and timing for both cams all the time.

Variable load and RPM scaling.

Honda scale their RPM points closer together where needed for fine tuning (see the red lines and arrows below). For example at idle and VTEC crossover the RPM points are 200-250 RPM apart. At high RPM the tuning points can be as far apart as 500 RPM. The same goes for load, although it is not as easy to see on these graphs.

What the graphs from this 95 GSR mean:

* The low speed and high speed fuel and ignition curves are vastly different.

* The shape of the fuel curves are very closely related to torque.

* After peak torque, less fuel is needed as can be seen below in the low speed cam fuel curve after 6000 RPM.





VTEC controllers

The ECU switches maps when the high speed VTEC cam is engaged. When an external VTEC controller is added, the cam is switched with the ECU running on the incorrect map for that cam. Depending on the RPM you can be as much as 10% fuel and 6 degrees ignition timing out. A typical VTEC controller will adjust 8 RPM positions by 2 load positions for a total of 16 tuning points. Compare that to 20 RPM positions by 10 load positions for each cam for a total of 400 tuning points. (* this is for a stock ECU. Hondata adds 240 tuning points for boost)

So in summary, external VTEC controllers upset the stock fuelling and ignition by switching the cam, have no ignition correction and very coarse fueling correction compared to the stock ECU.

Short and long term fuel trim.

OBD I and OBD II both have a function called fuel trim. If, at part throttle the ECU sees the air fuel ratio is too rich or lean the ECU makes immediate (short term) corrections. Over time those corrections are learned and transferred to a long term trim value that is applied all the time. Unplugging the ECU is one only way of erasing the long term value. So depending on how you alter the fuel with an external piggyback type controller, the ECU can learn and override it.


Article on hondata:
http://www.sportcompactcarweb.com/projectcars/0209scc_projciviceg/
More info:
http://d-series.org/viewtopic.php?t=2559

From Helms


OBD0 & OBD1 ECU error codes:
OBD0 Check Engine Light (CEL) Codes
When the Check Engine warning light has been reported on, turn the ignition on, pull down the passenger's side carpet from under the dashboard and observe the LED on the top of the ECU. The LED indicates a system failure code by blinking frequency. The ECU LED can indicate any number of simultaneous component problems by blinking seperate codes, one after another. Problem codes 1 through 9 are indicated by individual short blinks. Problem codes 10 through 44 are indicated by a series of long and short blinks. One long blink equals 10 short blinks. Add the long and short blinks together to determine the problem code.

you have to jump a service connector located on the passenger side right under the dashboard near the door. The connector has two pin inputs. Connecting them with something like a paper clip will force the check engine light on the dashboard to display the codes. when u pull the kick panel on the right side floor board where your ecu you there will be an extra plug hanging i beleive its green or blue, put the paper clip in it, turn the ignition to the on position and count the number of blinks on the check engine light.

codes 1-9 are indicated by a series of short flashes; two digit codes use a number of long flashes for the first digit followed by the number of short flashes for the second digit. So a code 43 will be represented by 4 long and 3 short flashes.

The position of codes in a sequence can be helpful in doing diagnostics. A display showing 1-1-1-pause-9-9-9 indicates two problems occurring at different times. A sequence showing 1-9-1-9-1-9 indicates two problems occurring at the same time.


Note: OBD0 is for ECUs in the years 1988 - 1991.

Self-Diagnosis
Indicator Blinks System Indicated
0 ECU
1, 2 Oxygen Content
3 Manifold Absolute Pressure
4 Crank Angle
5 Manifold Absolute Pressure
6 Coolant
7 Throttle Angle
8 TDC Position
9 No. 1 Cylinder Position
10 Intake Air Temperature
13 Atmospheric Pressure
14 Electronic Air Control
15 Ignition Output Signal
17 Vehicle Speed Sensor
21 Spool Solenoid Valve
22 Oil Pressure Switch
43, 44 Fuel Supply System (KX, KS, KG)


If codes other than those listed above are indicated, count the number of blinks again. If the indicator is in fact blinking unusual codes, subsitute a known-good ECU and recheck. If the indication goes away, replace the original ECU. The Check Engine warning light and ECU LED may come on, indicating a system problem, when, in fact, there is a poor or intermittent electrical connection. First, check the electrical connections, clean or repair connections if necessary. If the Check Engine warning light is on and LED stays on, replace the ECU.
***this was taken from the Helms manual for 88-91 Civics.
_________________
ECU Pintouts for OBD2b, OBD2a, and OBD1

http://www.autoserve.8m.com/


OBD2a OBD2b Function OBD1 Color Notes
A01 B05 Injector 4 A02 Yellow
A02 B04 Injector 3 A05 Light Blue
A03 B03 Injector 2 A03 Red
A04 B11 Injector 1 A01 Brown
A05 A08 SO2H No connection on OBD1
A06 C01 PO2H A06 Orange/black
A08 B12 VTS A04 Orange/White
A09 B20 LG1 A26 Black/Red
A10 B02 PG1 A23 Black
A11 B01 IGP1 A25 Yellow/Black
A12 B23 IACV A09 Green/White
A15 A06 PCS A20 Red
A16 A16 FLR A07 Green/Yellow
A17 A17 ACC A15 Black/Red
A18 A18 MIL A13 Green/Orange
A19 A02 ALTC A16 White/Yellow No connection on D16Y8 P2Nb
A20 B13 ICM A21 Red/Green
A22 B22 LG2 B02 Brown
A23 B10 PG2 A24 Black
A24 B09 ICP2 B01 Yellow Black
A27 A20 FANC A12 Yellow/Green
C01 C31 CKFP No connection on OBD1
C02 C08 CKPP B15 Blue/Green
C03 C20 TDCP B13 Orange/Blue
C04 C29 CYPP B11 Orange
C05 A27 ACS B05 Blue/Red
C06 A24 STS B09 Blue/White
C07 A10 SCS D04 Brown
C10 B21 VBU D01 White/Blue
C11 C22 CKFM No connection on OBD1
C12 C09 CKPM B16 Blue/Yellow
C13 C21 TDCM B14 White/Blue
C14 C30 CYPM B12 White
C15 C10 VTM D06 Orange/Green Connected to VTS on OBD2a
C16 A26 PSW B08 Brown/Red
C17 C05 ALTF D09 Pink No connection on D16Y8 P2Nb
C18 C23 VSS B10 Yellow/Blue
D01 C27 TPS D11 Pink/Black
D02 C26 ECT D13 Red/White
D03 C17 MAP D17 Pink/White
D04 C19 VCC1 D19 Yellow/Green
D05 A32 BKSM D02 Greem/White
D06 C03 KS D03 Red/Green No connection on P08, P28
D07 C16 PO2S D14 White
D08 C25 IAT D15
D10 C28 VCC2 D20 Yellow/White
D11 C18 SG2 D22 Green/White
D12 C07 SG1 D21 Green/Blue
D14 A23 SO2S No connection on OBD1
D16 A30 EL D10 Green/Red No connection on D16Y8 P2Nb



Dyno Chart for some chips:
http://www.autoserve.8m.com/ChipDyno.html
How to install a Chip on 88-91 OBD-0 Honda ECU
http://www.autoserve.8m.com/StepByStep_OBD0/Chip_Installation_OBD_0.html
How to install a Chip on 92-95 OBD-I Honda ECU
http://www.autoserve.8m.com/StepByStep_OBDI/Chip_Installation_OBD_I.html
How to install a Chip on 96-up OBD-II Honda ECU
http://www.autoserve.8m.com/StepByStep_OBDII/Chip_Installation_OBD_II.html
ECU INFO CENTER
http://www.autoserve.8m.com/Ecu_Info.html

Pin-Out Schematics :

!how to hook up VTEC
http://d-series.org/viewtopic.php?p=16011#16011
MPFI Wire Swap
http://www.slashandbang.com/MPFIwireswap.html
P28/P30 ECU Pin Out
http://www.hondaswap.com/articles/viewer.php?id=17
96-98 OBD2 Civic and Integra
http://www.we-todd-did-racing.com/wetoddimage.wtdr/i=wMTk5NzM4NnM0MTNkZmQzMXk1NDE%3D
99-00 OBD2 Civic & 99-01 Integra
http://www.we-todd-did-racing.com/wetoddimage.wtdr/i=wMTk5NzM5NnM0MTNkZmQzMXk1NDE%3D

Wiring Conversion 99Si to OBD1
http://www.hasport.com/Tech/Wring/Conversion%2099Si%20-OBD1.htm#

OBD 2.5 / OBD 1 / Terminal descrption

B11 A1 #1 injector
B3 A3 #2 injector
B4 A5 #3 injector
B5 A2 #4 injector
B1 A25 IGN power 1 for ECU
B9 B1 IGN power 2 for ECU
B2 A23 Power ground 1 for ECU
B10 A24 Power Ground 2 for ECU
B20 A26 Logic Ground 1 for ECU
B22 B2 Logic ground 2 for ECU
A6 A20 EVAP Purge control solenoid valve
A29 - Fuel tank pressure sensor
B12 A4 VTEC solenoid
- - Fuel pressure solenoid vlave
A16 A7 Fuel pump relay
- - Fuel pump relay
A18 A13 Malfunction indicator lamp
B13 A21
- - Igniter
B23 A9 IACV (EACV)
C16 D14 Primary O2 signal
C1 A6 Primary HO2 heater control
A23 - Secondary O2 signal
A8 - Secondary HO2 heater control
- A17 IAB (GSR)
A20 A12 Radiator fan control
- - Tandem valve control solenoid
C22 - CKF P
C31 - CKF G
C8 B15 CKP P
C9 B16 CKP G
C20 B13 TDC P
C21 B14 TDC G
C29 B11 CYP P
C30 B12 CYP G
A17 A15 A/C clutch relay
A27 B5 A/C switch
A24 B9 Starter switch signal
A10 D4 Service check signal (Ignition timing adjusting connector)
A21 - K-Line
B21 D1 DTC memory voltage
C10 D6 VTEC oil pressure
A26 B8 Power steering pressure switch
A32 D2 Brake switch signal
C5 D9 Alternator FRsignal
C2 A16 Alternator control
C26 D13 ECT
A30 D10 ELD
C25 D15 IAT
- - PA
C27 D11 TPS
C23 B10 VSS
C28 D20 Sensor voltage
C18 D22 Sensor ground
C17 D17 MAP
C19 D19 Map sensor voltage
C7 D21 MAP sensor ground
C3 D3 Knock sensor



Wiring Conversions
http://www.hasport.com/Products/Wiring.htm
_________________

VTEC switch point
http://hondata.com/techk20vtecswitchpoint.html

We are learning that the VTEC switch point is very important for the power curve.

In this example below of a K20A2 with CAI , we switched the VTEC point on at 5200 RPM instead of 5800. This provided a substantial gain in torque and power from 5800 to 6600 rpm - after the old VTEC switch point. The VTEC dip was minimised by switching just before a lowcam 5300 torque peak.

Why? We suspect that the airflow to the engine takes a while to reestablish after the VTEC switch point. The results speak well. About 10 ft/lb and 12 hp gain at 6000 rpm.

Injector Wiring

High horsepower boosted cars often need large injectors. Most large capacity injectors are available in peak and hold form - about 2 ohms impedance, whereas most stock injectors from about 92 on are saturated (8-10 ohms impedance). Honda engine computers require a total injector impedance of about 10 ohms so a resistor pack is needed whenever the stock saturated injectors are swapped with peak and hold.

Early model injected Hondas; 90-95 Prelude and Accord; 89-91 JDM B16A Hondas all ran external resistor packs with low impedance injectors.

This wiring diagram shows the wiring for saturated (upper), and peak and hold injectors (lower). The engine computer activates the injectors by grounding each injector in turn.



Converting to Peak and Hold injectors

Near the brake master cylinder on OBD I cars is a connector that distributes power to the injectors and a number of sensors. Verify with a multimeter which wires go to the injectors. Cut all 4 and connect the wires coming from the injectors to the resistor pack. Connect the power wire from the resistor pack to all 4 of the unused wires coming from the power connector. OBD II cars may have this connector somewhere under the intake manifold.

[DOHCDX]

this is the info to end all VTEC wiring info. big thanks to my buddy christian:

There are always a lot of questions about wiring up VTEC in your civic. It can be somewhat intimidating. Below is a diagram I made of the wires that will need to be added to complete a VTEC swap in your OBDI 5th gen civic.
http://www.expericenter.com/images/chris/wiring.gif

There are a few side notes:
Both of the following VTEC wires are already wired up on the 92 hatchbacks from the ECU to the shock tower connector.
VTEC Solenoid: The wire at the ECU (pin A4) starts out as an orange/white wire. It then turns into a green/yellow wire. It finnally turns into a green/white wire, which is what color the wire on the connector should be.
VTEC Oil Pressure Sensor: The wire at the ECU (pin D6) starts out as an orange/blue wire. It then turns into a blue/black wire, which is what color the wire on the connector should be. The connector also has a black wire comming from it. This needs to be grounded. From the factory, it follows the harness to the maingrounding block on the thermostat, but can be grounded anywhere you see fit.
Knock Sensor: This will need to be wired up regradless from the ECU. The wire is red/blue at the connector.
Secondary Intake Solenoid: This will also have to be wired from the ECU regardless. The wire color is pink/blue at the connector.


To install a:
D series motor with VTEC: Youll need to wire up the VTEC Solenoid and Oil Pressure Sensor and Ground.
B16A: Youll need to wire up the VTEC Solenoid, Oil Pressure Sensor and Ground as well as the Knock Sensor.
B18C1: Youll need to wire up the VTEC Solenoid, Oil Pressure Sensor and Ground as well as the Knock Sensor and Secondary Intake Solenoid.

Here is a pic of the ECU pinouts for the OBDI ECU:
http://www.hybridgarage.com/tech/info_files/eg-pin.gif
Thanks to www.hybridgarage.com for that photo!

[DOG]

DOHCDX - Great addition!