EFI wiring guru needed. what are these wires?

[Danish 294]

TBH i thought it only read 94 on ECUs, that's what the manual says anyway ?

 

As I said it is more likely that you are right.

 

But when my "LED box" is plugged in, it definitely does the "flicker". Maybe there is an older Ford diagnostics box than the FDS2000?

[bortaf 96]

As I said it is more likely that you are right.

 

But when my "LED box" is plugged in, it definitely does the "flicker". Maybe there is an older Ford diagnostics box than the FDS2000?

 

It may well read it i'm not sure TBH, i only read up on them cos i got offerd one years ago but TBH the pinto EFi is so simple it doesn't need a reader, there's only the TPS, AFM and water temp to read no MAP, Lamda or CPS so i never botherd then i got into diesels and they have nowt to read :D

[Danish 294]

It may well read it i'm not sure TBH, i only read up on them cos i got offerd one years ago but TBH the pinto EFi is so simple it doesn't need a reader, there's only the TPS, AFM and water temp to read no MAP, Lamda or CPS so i never botherd then i got into diesels and they have nowt to read :D

 

How do you actually tune an EEC-IV then? I know I have to use a stand-alone lambda sensor. How do I change the fueling?

[buzzard 13]

How do you actually tune an EEC-IV then? I know I have to use a stand-alone lambda sensor. How do I change the fueling?

fueling is controled buy the fuel reg , crudely put buy me . if it was just a cam a adjustable raise the rate could help . turbo/supercharge . injectors + fuel reg . but its like tuneing a carb , its hard across the whole of the rev range . lean at the top rich at the bottom . if you know what you mean . i do have a chip up graded ecu . that adds more fuel and proberly more . other than these i carnt think of any thing else that would help adjust/control fueling . cear as mud as usual.

[Danish 294]

Thanks Buzzard, so it really is very simple. :thumbup:

[simmo490 0]

Well I have my pump priming and cranking but I have not put the fuel lines know yet. I can already see a problem though. When cranking the fuel pump drops out but when releasing the key it momentarily comes back in again. Also noticed no taco on cranking. Wonder if I have a big volt drop on cranking knocking out the ecu. Will put jumps on it

[bortaf 96]

Thanks Buzzard, so it really is very simple. :thumbup:

 

Yep :) you can also adjust the preload on the AFM spring so it takes more/less air to open the flap, it is adjustable form the outside but bigger gains can be had by opening it up a cranking the ratchet, had to do it an a few jags to sort over fueling (same AFM).

 

The pinto is a really a guessing ECU, it knows what is going in but has no idea what's coming out (no lambda) so any change or fault after the sensors isn't picked up and corrected like it is on the later twinks with lambda (closed loop).

If you want to really get into it try here http://www.tweecer.com/downloads.htm but TBH i'd start with a later closed loop ECU from a ttwink and mod from there, no need for an external lambda but you'd need a CPS (cossie cps and mount?) for the later ECU.

I have seen a pinto EFi run on cossie managment just cos it's easyer to mod the cossis managment (weber marelli) to take into account hotter cams and fueling adjustments, have a look here for WM and later EECIV http://www.motorsport-developments.co.uk/rs_cosworth_ecu_chips.html

TBH by the time you've done all that megasquirt would be cheaper and easyer, that's why i gave up on the idea and then gave up on the pinto engine (seriously) a twink is way better than a pinto "IF" (big if) you look after it (pinto is way tougher) and you can start with closed loop (if you get the later engine) and it'll return 40+ MPG comfortably on a run, which no pinto will ever do (low VE) without some seriouse driving technique.

[bortaf 96]

Well I have my pump priming and cranking but I have not put the fuel lines know yet. I can already see a problem though. When cranking the fuel pump drops out but when releasing the key it momentarily comes back in again. Also noticed no taco on cranking. Wonder if I have a big volt drop on cranking knocking out the ecu. Will put jumps on it

 

You need the black wire to be on a perminant ign live NOT one that drops out during cranking ;) there is one there just test at the IGN switch which one stays live during cranking :thumbup:

P.S dont live up the pump too often it's doesn't take long to burn them out without fuel to cool and lube them :thumbup: also the dizzy really REALLY doesn't like cranking without starting, they blow rather easyly, had 2 go on my first conversion just trying to start the dam thing and had 2 others go on already converted cars when the owner tripped the fuel shut off with shopping and didn't realise, by the the time they realised they had killed the battery trying to start the car and the dizzy :headscratch:

[simmo490 0]

Hi thanks all. She lives and looking and sounding pretty sweet. The problem was a large volts drop dropping out relay because of my duff battery. Now I just need to work out which wires to earth on the octane wires: ( thanks for all the help

[bortaf 96]

Do you not have a ring connection on the end of the octain wires? usually there 3 wires go into a plug and the other end of that plug is a single yellow wire that earths?

TBH i just set the timming at 8Deg BTDC and that's that, leave the octain wire off, it only re alters the base timing again so if you earth it then set the timing it's made no differance at all.

It is usefull if you turbo the engine then you can earth variouse combos of wires through pressure switchs to rretard the ign on boost otherwise just set it and leave it be, at the factory the base timing was set sonicly somehow and the factory veiw is the dizzy should never be alterd so you use the wires to set the engine for differant petrol types, in reality it makes no odds if it's earthed or not you just turn the dizzy to set the timing as with any engine with a dizzy :)

Mainly about US versions but a breif rundown of how the EEC IV operates, note pinto's are only closed loop on later transit vans but a lot of it is relevant ;)

http://www.veryuseful.com/mustang/tech/engine/EECIVInnerWorkings/

OHC and DOHC EFi systems.pdf

[Captain Scarlet 96]

 

 

don't forget to replace ballast wire with a normal piece.

 

You had me going there,i couldnt remember taking mine off (well ,its been about 6 years ago :rolleyes:) i had to go and check it out,+ feed reading 11.5V ish and 13.5V ish running :thumbup:

[VHKcappa 0]

On 8/4/2013 at 1:03 PM, bortaf said:

 

Yes there is, there's a 3 pin diagnostics socket that just flashes an LED reader to give you codes ;) (the socket with the rubber cap on it)

Any use ? early loom so dizzy is differant, i'll look see if i have a later loom pic labled

 

Hey I have the above wiring harness and I was wondering if u can give a hand at helping me wire this to my capri. It won’t let me send any photos as the file size is to big do you have an email I could contact you on

[bortaf 96]

On 12/7/2025 at 11:29 AM, VHKcappa said:

Hey I have the above wiring harness and I was wondering if u can give a hand at helping me wire this to my capri. It won’t let me send any photos as the file size is to big do you have an email I could contact you on

fatrob83@hotmail.com

what do you need to know ? it's been a while but i'll help where i can