fiestaturbo.com

[Andy.B]

Right ppl i have have compiled a full set of loom changes for any XR2i 8v loom to OFAC or OFAB and from OFAC to OFAB.

These pin changes alow you to run FRST management without an Amal valve, if you decide to add an amal valve for a reason you will need to take a pin out of a scrap EFi Ford ECU plug and run a wire from one side of the new AMAL valve to ECU pin 33. The other side of the amal valve plug goes to a good earth point or any plain brown wire.


Converting an 8v 2i loom to OFAB

1) At the ECU, pin no. 27 (marked on the multiplug, brown wire) needs moving to pin 8, which is empty (this is the CO adjuster signal wire).
2) Pin no. 45 (brown/yellow) needs moving to pin 27 - this is for the MAP sensor.
3) EDIS Module pin 2 (blue/yellow) may now be disregarded as it is not used by the 0FAC ECU (pin 28 on ECU).

MAP Sensor re-wire:

At the MAP sensor multiplug...
1) Move the brown wire (gnd) to cossie MAP sensor pin no. 1 (marked on multiplug).
2) Move the brown/trace* wire (feeds back to ECU on pin no. 26) to cossie MAP sensor pin no. 2
3) Move the brown/yellow wire (feeds from pin no. 27 on the ECU) to cossie MAP sensor pin no. 3
4) On one of the Cossie MAP Sensors fixing holes there is a metal ring which goes into the sensor. This ring must be earthed, and when you mount the Cossie map sensor using the right brackets, it connects to earth. (You should only ever mount the Weber/Cosworth MAP sensors with the vacuum pipe pointing downwards).


Converting an XR2i loom to OFAC

1) Pin no. 8 (brown) needs moving to pin 27, which is empty (CO adjuster signal wire)
2) Pin no. 27 (brown/yellow) needs moving to pin no. 45
3) EDIS Module pin 2 (blue/yellow) may now be disregarded as it is not used by the 0FAB ECU (pin 28 on ECU).


There are no MAP sensor pin changes as the OFAC MAP sensor is the same plug as the 2i MAP Sensor, so just plug and play.



OFAB to OFAC

Revert back to (OFAC) with these pin changes on the MAP Sensor. These changes assume you have the MAP sensor sitting with the part code (stamped in the side of the sensor) and plug locking latch facing you.

1) Move Cossie MAP pin no. 1 to pin no. 3 (brown).
2) Move Cossie MAP pin no. 2 to pin no. 1 (brown/trace*)
3) Move Cossie MAP pin no. 3 to pin no. 2 (brown/yellow)



* brown and trace denotes any colour trace as i have come across many colours but usually it is either a green or a black trace.

Hope this helps ppl i know its been a long time comming but I've had to prove all this on my own car and other peoples looms so lots of reserch, but this info should work!

Thanx

Andy

Sorry for the boo boo made in the guide, when i was typing this out i cocked up. Its all edited out now and is correct with the other information on the site (Scort)

[SimonT]

Andy your a star mate!

I also need to talk to you about some zetec headwork

[jdfiesta]

very informative that!
JJ

[maysaXr2i]

GOD

you dont know how good your timing is!!! - i pulled the lump out of my turbo last night and have spent the dday looking for an OFAC loom to replace my FRST - now its not needed

WELL DONE THAT MAN!!!!!!

[Farooq]

hi mate i was told that you only need to move one wire when doing the ofac as moving the other wire cant remember waht one makes the car way over fuel well thats what i was told can u tell me if u know anything about that?

[Andy.B]

Sorry mate what you have been told is wrong. These ARE the pins needed to change the 2i loom over to OFAC and OFAB and visa versa. You will need to move the 2 wires stated in the guide. If you dont move the Co2 wire to that pin you will have no Co adjustment at all, prob make it run rich if you dont move that. And you deffo need to move the other Brown an Yellow wire because there will be no signal going from the MAP sensor to the ECU. The EDIS is also taken out, because if you dont the car runs poo, not to sure on the reason why but it does.

Hope this helps mate.

[Farooq]

i take it by taking the edis out u mean remove pin 2.sorry i hope i havent offended u as u can appreciate im getting told that mmany things ur thinking to yorselves omg what is right and wrong it rather confusing all the best mate

[Andy.B]

No no no mate u havent offended me at all. Yes i meen take pin 2 outa the EDIS module. So jus follow the instructions above and you will have a fully working OFAC loom Just make sure u have a OFAC MAP sensor and ECU and you can do no wrong

[StreetDragster]

OFAB to OFAC

Revert back to (OFAC) with these pin changes on the MAP Sensor. These changes assume you have the MAP sensor sitting with the part code (stamped in the side of the sensor) and plug locking latch facing you.

1) Move Cossie MAP pin no. 1 to pin no. 3 (brown).
2) Move Cossie MAP pin no. 2 to pin no. 1 (brown/trace*)
3) Move Cossie MAP pin no. 3 to pin no. 2 (brown/yellow)

Can i just clarify this.....
If i'm changing an OFAB FRST to OFAC, i need the OFAc ECU, the OFAC Map Sensor, and to do the above mods only??
Thanks for any help, supposed to be doing this on a friends RS Turbo very soon, great guide BTW

Thanks Again

Matt

[Andy.B]

Yes you will need those things u stated plus u will need the OFAC type plug for the MAP sensor, as the OFAB plug is just your usual clip on type, like the one you have on the coil pack just smaller. You can get the plug off any 2i loom as they use the same style MAP sensor as OFAC.

[Andy.B]

Frickin 6 posts al i did was click twice

[Andy.B]

[Andy.B]

[Andy.B]

[Andy.B]

[Project]

Numpty

Streetdragster - you'll also need the FRST IAT sensor

Everything else you can use 2i kit on iirc.

[Farooq]

where can i get one of these FRST IAT sensor has any1 got one is it essential?

[StreetDragster]

Cool, thanks very much!

Streetdragster - you'll also need the FRST IAT sensor

Doing a swap from OFAb to OFAC on a FRST so hopefully it wil alrady have the right IAT sensor, but now i know exactly what to look for to check its the right one

Thanks again

Matt

[Andy.B]

U will need the FRST IAT sensor Farooq as if you use the 2i one you will have problems when your ACT's hit around 40 degrees. You can get the sensor from Fords still about £35 if i remember right.

[~Tony~]

wicked mate i will defo have a look at this

[maysaXr2i]

2 questions - gonna make me sound abit thick lol

1) EDIS Module pin 2 (blue/yellow) may now be disregarded as it is not used by the 0FAC ECU (pin 28 on ECU).

Can i just remove pin number 28 from the ecu plug or do i have to remove it from the EDIS module, if s whre is this???

2)

U will need the FRST IAT sensor Farooq as if you use the 2i one you will have problems when your ACT's hit around 40 degrees. You can get the sensor from Fords still about £35 if i remember right.

could this be what i need aswell?? - my car idles fine but when you drive the turbo begins to spin, then you feel it hold back and it kangaroo's if you keep your foot down.

[maysaXr2i]

i moved the CO adjuster signal wire back to its original pin and the car is running fine now???

[InS@nE]

i do have one question


i ran my turbo conversion on ofac on standard efi loom with no changes and it ran fine as most folks who went in it on here will tell you.

i also have the ford wiring diagrams for the ecu and they show no changes in the ecu pin outs for the ofac and 2i. as only difference is the ecu read + form map instead of -

[chubba]

xr2i loom checked my plug for the ecu and it looks like a proper frst one as all the pins are in the places you recommend for ofac but my mate who had the car before ran like crap i just took out the ecu and found an ofab
i,ve checked as much as possible with the wires and map senser i might be lucky and get away with the ofac ecu.
could you try and discibe the map senser and housing and bit`s around for ofac
thanks carl

[Project]

Trust what Andy.B has said (several times) One point - the only changes to convert from 2i 8v to 0FAB are to change the MAP sensor connector and cut the wire to pin 2 of the E-DIS module.

Al

[alti]

I have also ofab ECU.
if I attach the map sensor on pin 45,
and co poti on pin 27,the engine runs very lean and kangaroo´s
with pin 27 and 8 the engine runs much better,
(0,99 lamda 3,4 %co without cat)
but without boost limit.
I really dont know whether the map sensor is broken,
or on the wrong pin.
perhaps you can help me

thanks alti

[Dr_x2]

guys, sorry, but i have checked the haynes squematics, and to convert 2i to OFAC, it is only to cut a wire (disable ecu pin 28)? i am i wrong?
thanks!

[Andy.B]

Mate what you read in the haynes manual is for a 2i unless stated. This listing was compiled from a very reputable tuner who does this kind of stuff all day long and also advised me on how to do this. I have also tried both of these conversions on a 2i loom and it works well, i am also swapping a OFAB loom over to OFAC so i know these instructions are correct. It has been knowen for some OFAC setups to work as a plug and play and i have no idea why as they shouldnt unless the ecu has some sort of bridging between pins on the board (Cant say i have looked)

Anyway as i say this is only a guide and some friendly advice that i have found out for myself and i thought i would share it with others as a reference.

If anyone thinks they know better please dont keep saying im wrong and this is goes x to the y ect ect....... I have had alot of PM's regarding the integrity of this post and its kinda getting on my nerve's now, so please keep it to your self.

DR_x2 i am not having a go at you and please dont take it that way, its just i get PM's saying are you sure its this that and the other. In the long run I wouldnt have put up this information if i did know it was incorrect.

Thanx all

Andy

wowthatsgotalotofmychest

[Project_XR2i_Trackcar]

sorry to sound like a muppet but,

could someone explain the abreviations please (ie OFAC/OFAB/EDIS etc) and to what engine conversion they correspond with

ie

cvh 8v turbo - 2.0 16v zetec turbo
cvh 8v - 2.0 16v zetec NA

etc etc

i'm sure this would help others too

cheers

[Andy.B]

Right ho no problem i dont mind questions like this.

OFAB and OFAC are the 2 styles of ecu used by fords by the FRST there was even an OFAA ecu but they are few and far between.

The OFAB ecu uses the Marelli style MAP sensor to detetect the boost pressure.

The OFAC ecu uses a Ford inspired MAP sensor.

EDIS stands for Electronic Distributerless Ignition System i think (dont quote me on that) but thats what it does....

The EDIS controls the spark through the boost curve so it advances the and retards the spark acordingly.

These two systems are used on the CVH turbo engine.

The zetec uses internal EDIS in the ecu in the newer engines ie when you use a 2.0 DEEP ecu it has the EDIS built in, but some of the older XR2i Zetecs used the external EDIS like the turbo which is bloted to the back of the engine bay on a plate.

Think thass about it

[alti]

perhaps someone has a photo with all wires
from the original ofab/ofac ecu plug?

tahnks alti

[Captain Tightpants]

Helpfull information!

Firstly a brief description of how and why:

Introduced in 1990. The EEC-IV module is the heart of the electronic engine control system and is based on a microprocessor-controlled electronic circuit. It compares signals from its various electronic sensors with stored engine operating parameters, varying the engines operating settings directly according to engine load and environment.
Ignition is electronic via a DIS (Distributerless Ignition System) coil and E-DIS 4 module. From signals generated by the crankshaft position sensor (CPS), the E-DIS 4 module generates a profile ignition pulse (PIP). From this PIP, the EEC-IV module calculates a Spark Advance Word (SAW) as a means of defining ignition timing (or firing point). The E-DIS 4 module uses the SAW signal to control the DIS coil. If the EEC-IV module develops a fault, a Limited Operation Strategy (LOS) comes into effect allowing the driver to continue the journey but with restricted power and economy. Under LOS conditions SAW and PIP signals are not used.
The EEC-IV module is provided with a memory which is used for control matching, diagnosis and self testing.
With the engine running the E-DIS 4 module receives the SAW signal in a 'window' extending from 10 degrees ATDC to 170 degrees BTDC. The signal is therefore outside the ignition advance and retard range (10 degrees ATDC to 57 degrees BTDC) and cannot be influenced by HT disturbances.
When the engine is started or running at low speed, or operating in LOS mode, ignition is triggered by the E-DIS 4 module at 10 degrees BTDC and is not controlled by the SAW.
The DIS ignition coil consists of two coil windings converting the voltage signal from the E-DIS 4 module into HT and supplying this HT to the spark plugs in the correct firing order.
The crankshaft position sensor (CPS) is an inductive proximity switch reacting to the 36 webs cast onto the rear of the flywheel. One web is missing causing a gap and is used to denote 90 degrees BTDC on number one cylinder in the firing order. The signal generated by the CPS is used by the E-DIS 4 module to determine actual ignition timing. On engines with an open loop principle (as opposed to those with a closed loop incorporating a catalyst and HEGO sensor), the CO adjustment, a 5 kohm potentiometer supplies a substitute CO value to the EEC-IV module in place of the HEGO sensor. (Heated Exhaust Gas Oxygen Sensor).

Moving swiftly on, here is a wiring diagram of the FRST engine loom:



This covers the main parts of the EEC-IV, it does not include the EDIS-4, however that is fairly self explanitory.

A photograph of an OFAC engine loom:



Key:
1: ECU
2: MAP sensor
3: Diagnostics connector & CO Idle adjust connector
4: Current return
5: EDIS-4 connector
6: Crank Position Sensor
7: Connector to engine loom (injectors etc)
8: Speed Sensor
9: DIS Coil
10: Oil pressure switch
11: Amal Valve
12: Current return
13: Idle Speed Control Valve
14: CO Adjust POT
15: Connector to car loom

The connector to car loom is configured in the following way:


Looking onto the engine loom connector

Pin 1: Ignition Live
Pin 2: Pin 22 (ECU) to the Fuel Pump Relay
Pin 3: Fed From DIS coil pack to the Rev counter
Pin 4: Pin 20 (ECU) Current return
Pin 5: Pins 57 & 37 (ECU) to the Fuel injection Relay
Pin 6: Oil Pressure
Pin 7: B+ (Constant Live)

Some more wiring colour information: ECU Pinout details,

1, Red -- +ve
3, Brown/Yellow – octane / idle adjust
4, Brown/White – speed sensor
7, Brown/Green – engine temperature sender
16, Brown – current return & 40
17, Brown/Green – diagnostics connector
20, Brown – current return
21, Brown/Yellow – idle speed valve
22, Brown – fuel pump relay
23, Brown/Red – octane / idle adjust
24, Brown/Blue – octane / idle adjust
25, Brown/Yellow – air temp sensor
26, Brown/Black – throttle sensor & co adjust pot & map sensor
27, Brown – CO adjust potentiometer
28, Blue/Yellow – Pin 2 on edis (disconnected)
33, Brown/Green – Boost control valve
36, Blue/Red – Pin 3 on edis
37, Black – idle speed valve & injectors & Speed sensor & Boost control (tbc) & 57
40, Brown – current return & 16
45, Brown/Yellow – map sensor
46, Brown – map sensor & engine temp & air temp & throttle & CO adjust
47, Brown/Green – throttle sensor
48, Blue/Green – diagnostic connector
56, Blue/Yellow – Pin 1 on edis
57, Black – idle speed valve & injectors & Speed sensor & Boost control (tbc) & 37
58, Brown – Injectors
59, Brown – Injectors
60, Brown – current return

Some of the above information is saved from a very oily notepad, so there is likely to be some arse ups, if there are tell me and I will change them.

Hope they are of some help to a few peeps!

Steve

[Project_XR2i_Trackcar]

cheers guys

still portugese to me but its getting clearer the more i read through it.

Scort - i know you posted those pics for me earlier, i had a look at mine today (1800 16v loom) and laid it all out to mark it up but i stopped as it seems slightly different, although not too disimilar mind.

If i posted a pic of my engine loom up could someone identify the connectors as per scorts pics.

I think this would be a massive help, not only to myself with my current CVH 8v - zetec 2.0 16v NA conversion but, for my conversion guide in members gallery

cheers
chris

[alti]

hi!

scort- 24, Brown/Blue – octane / idle adjust
25, Brown/Yellow – air temp sensor
26, Brown/Black – throttle sensor & co adjust pot & map sensor
27, Brown – CO adjust potentiometer
28, Blue/Yellow – Pin 2 on edis (disconnected)
33, Brown/Green – Boost control valve
36, Blue/Red – Pin 3 on edis
37, Black – idle speed valve & injectors & Speed sensor
40, Brown – current return & 16
45, Brown/Yellow –MAP sensor
46, Brown – map sensor & engine temp & air temp & throttle

this must be the pinout to the loom in the picture
but the plug on the photo is the xr2i style- OFAC
is this true?

thanks alti[/u][/url]

[Captain Tightpants]

A bit of an update. Andy.B, sorry if any of this information contradicts any of your above statements. I am not saying your wrong, just that Ford must have made different type looms.

People, if your doing any conversions, the best way is to bell out the cables, using a meter.

Firstly, anybody who has converted to OFAB, from OFAC, or N/A EEC-IV. This is important!! What has not been included in the above is the essential use of a MAP supressor! The supressor is a black box, about 30mm square and 8mm deep, it has three wires coming out of it, and is located on the bulkhead near the MAP sensor.

It is connected in the following way: (excuse the crumby diagrams!)



If you do not have this connected, you run the risk of damaging either/or the MAP sensor or ECU. It will also feed the ECU incorrect information, causing running problems, and/or damage to the engine. It may seem however that the engine is running with no problems.

A diagram of the MAP sensor and supressor plugs, looking on to them, at the engine loom.



It's worth noting, that these supressors are no longer available from Ford, and when they were available, they were £100 odd!

However, if you need one, speak to Kenny at Motorsport Developments,
Unit 3F, Moor Park Industrial Estate, Kincraig Road, Bispham, Blackpool, Lancashire, FY2 0HF, 01253 508400. He will supply you one new for £50, delivered.

Here are my pinout findings for OFAB,

1, Red -- +ve
3, Brown/Yellow – octane / idle adjust
4, Brown/White – speed sensor
7, Brown/Green – engine temperature sender
8, Brown – CO adjust potentiometer
16, Brown – current return & 40
17, Brown/Green – diagnostics connector
20, Brown – current return
21, Brown/Yellow – idle speed valve
22, Brown – fuel pump relay
23, Brown/Red – octane / idle adjust
24, Brown/Blue – octane / idle adjust
25, Brown/Yellow – air temp sensor
26, Brown/Black – throttle sensor & co adjust pot & map sensor
27, Brown/Yellow – map sensor/via supressor
33, Brown/Green – Boost control valve
36, Blue/Red – Pin 3 on edis
37, Black – idle speed valve & injectors & Speed sensor & Boost control (tbc) & 57
40, Brown – current return & 16
46, Brown – map sensor & engine temp & air temp & throttle & CO adjust
47, Brown/Green – throttle sensor
48, Blue/Green – diagnostic connector
56, Blue/Yellow – Pin 1 on edis
57, Black – idle speed valve & injectors & Speed sensor & Boost control (tbc) & 37
58, Brown – Injectors
59, Brown – Injectors
60, Brown – current return

I have now done three OFAC conversions, and two OFAB. One of the OFAC was from a XR3i loom.

Here is where I contradict what Andy.B says above, and again mate, I can only assume that there are different types of loom, or ECU builds. Its well worth belling these wires out as I said before!!

Converting an 8v 2i loom to OFAC

1) EDIS Module pin 2 (blue/yellow) may now be disregarded as it is not used by the 0FAC ECU (pin 28 on ECU).

There are no MAP sensor pin changes as the OFAC MAP sensor is the same plug as the 2i MAP Sensor, so just plug and play.


Converting an OFAC loom to OFAB

1) At the ECU, pin no. 27 (marked on the multiplug, brown wire) needs moving to pin 8, which is empty (this is the CO adjuster signal wire).
2) Pin no. 45 (brown/yellow) needs moving to pin 27 - this is for the MAP sensor.

Any questions just ask,

These are MY findings, and not gospel.

Steve