wiring a 3.9 serperntine injection system into racer?

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hybridv8
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wiring a 3.9 serperntine injection system into racer?

Post by hybridv8 »

hi all
im trying to wire a 3.9 injection system into my racer via the 7 pin plug,
but carnt find any info with my wire colours ,its out of a landrover discovery
colours are
large purple/white
large brown/green
white/ purple
brown/red
black/green
white/green
black/red
also there are 2 blue and white wires with resistors which i think are coil negative and a green and white wire
i think i need to use 3 from the plug but which ones?



texpis
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Post by texpis »

There's a sticky above your post with hall the info on the hotwire efi wiring

Mick

hybridv8
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Post by hybridv8 »

mick thanks for reply but i carnt find anything with my wire colours above..

DaveEFI
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Post by DaveEFI »

This is the diagram I have for late hotwire:-

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richardpope50
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Post by richardpope50 »

Plus this (copied from spreadsheet so you'll have to work it out):
Original loom from a 1998 TVR Griffiths 500
This is a detailed list of ECU pin-puts that I compiled from modifying my TVR loom for my Dax Rush kit car.
"My TVR EFI loom was a standard Land Rover loom so the following is common to all Land Rover EFI looms. ECU is a 14CUX version (latest ever made).
Where it says 'not used by TVR', it simply means I did not find a wire attached to this pin. It is probably the same in any LR / Rover loom too but I do not know that.
"
Note that my loom had several connectors to the outside world and are probably used for connecting to the dashboard, etc.. As I was completely re-arranging my loom I was able to remove these connectors and incorporate the connections into my 'new loom' - it is probable you can do this too unless you do not want to bother. I also made several other mods but these are not shown here as they may confuse the base loom wiring

Columns:Pin, Purpose & Notes

Outside World Connectors
Clear plastic connector Totally removed Unknown use.
Brown plastic connector Totally removed Unknown use.
Black connector - Can be totally removed
1 Connects lambda sensors with an earth circuit via the black connector but these are also earthed from a splice point via loom connection to earth via the engine. Therefore this pin and wire not required from this splice point back to this black connector (as engine earth will do).
5 Not used by TVR
8 & 4 Pin 8 is 12v ignition on feed from Blue harness connector (pin 19) and pin 4 is then this onwards 12v feed to coil. Therefore by re-routing pin 4 direct to Blue harness pin 19, neither black harness pins 8 & 4 are required.

Columns: Pin, Purpose,Notes & Wire colours (main + trace)
Blue plastic jumper connector
1 (Link A) Kept as is To ECU pin 27 Black + Grey
Note that these Blue Connector links are just a set of jumpers linking sets of pins together
2 (Link A) Kept as is To loom Black
3 (Link A) Kept as is To diagnostic socket Black + Grey
4 (Link A) Removed
5 (Link A) Not used by TVR
6 (Link A) Kept as is To tune resistor Black + Grey
7 (Link B) EFI main relay, pin 87. From ECU pin 2 Brown + Orange
8 (Link B) Kept as is 12v feed to injectors and EFI sensors Brown + Orange
9 (Link B) Kept as is 12v feed to injectors and EFI sensors Brown + Orange
10 (Link B) Removed
11 (Link C) Not used by TVR
12 (Link C) Kept as is To ECU pin 25 Red + Black
13 (Link C) Kept as is Ground circuit to loom Red + Black
14 (Link C) Kept as is Ground circuit to loom Red + Black
15 (Link C) Kept as is Ground circuit to loom Red + Black
16 (Link C) Kept as is Ground circuit to loom Red + Black
17 (Link D) 12v ignition on feed From ignition switch White + Green
18 (Link D) 12v ignition on feed to EFI ECU pin 19. White + Green
19 (Link D) Originally connects to coil via the black connector, now direct connection to coil 12v feed to coil +ve terminal Black
20 (Link D) 12v ignition on feed to fuel relay White + Green


ECU Pinouts and the changes for my Rush
1 Idle air control valve with ignition on - output Red + Green
2 12v feed to main EFI relay when ECU grounds pin 12 and switches it on. (Same feed also goes to injector circuit and lambda sensors) via blue plastic jumper (above). Brown + Orange
3 Output to throttle position sensor with ignition on - See also pins 20 & 25 Yellow
4 Ground but note this pin was not used on non-Cat engines. Connects direct to ground via ign module's chassis plate (strange connection!) Black
5 Tune resistor to switch ECU to cat, non-cat, etc. Settings. Paired with pin 27 Note Green (446 to 494 ohm) resistor for non-cat operation, white for cat operation Grey + Black
6 Receives signal from vehicle speed sensor whilst vehicle moving Yellow + Pink
7 Engine coolant temperature sensor input with ignition on - see also pin 25 Green + Blue
8 Senses if heated windscreen is on Not used by TVR
9 Connects to diagnostic socket White + Pink
10 ECU warning light – ECU grounds this pin to switch light on Means there is a problem but you do not know what! Guess you buy an expensive de-coder. Red + Grey
11 ECU grounds injectors to fire cyl 2,4,6,8 Yellow + White
12 ECU switches on its main control relay by grounding relay pin 85 Blue + red
13 ECU grounds injectors to fire cyl 1,3,5,7 Yellow + Blue
14 Ground and links to pin 40 Connect direct to ground via EFI loom Black
15 Main permanent 12v battery voltage input Brown + Orange
16 EFI ECU ground to switch on fuel pump via grounding fuel pump relay pin 86. Blue + Purple
17 Earths emmissions canister purge valve control & vents fuel tank (cat engines ). I removed canister in my car so not used and wire removed too.
18 Connects to diagnostic socket White + Light Green
19 12v feed to ECU when ignition switch is switched on Connects to blue jumper connector pin 18 White + Green
20 Input voltage from throttle position sensor - see also pins 3 & 25 Red
21 Senses if air conditioning on via refrigerant pressure switch (if aircon fitted and to boost engine idle speed to compensate for aircon pump) Not used by TVR
22 Input voltage from air flow sensor. Red + Blue
23 Input reading from left hand (passenger's) heated Lambda oxygen sensor but note this pin is not used on non-Cat engines. Thick Blue (Shielded) + white tag
24 Input reading from right (Driver's) heated Lambda oxygen sensor but note this pin is not used on non-Cat engines. Thick Blue (Shielded)
25 Ground side of engine sensor circuit for fuel temp, coolant temp, throttle position (throttle potentiometer) & air flow sensors Connects via blue jumper connector pin 12 Red + Black
26 Idle air control valve while ignition switched on Green + White
27 Tune resistor ground. Linked with pin 5 (and also diagnostic socket via blue harness pin 3) TVR loom earths via blue jumper connector pin 1 Grey + Black
28 Idle air bypass control valve circuit 2 Blue + Grey
29 Idle air bypass control valve circuit 2 Orange
30 (Fault display data, when display module is used but note this pin is not used on non-Cat engines.)
31 ECU 'request' connection for a connected diagnostic meter but note this pin was not used on non-Cat engines.. Not used in actual TVR loom (but is in their wiring diagram as well as LandRover's diag but marked as not used.
32 Input signal from fuel temperature sensor - see also pin 25 Grey + White
33 Senses air conditioning compressor clutch relay (Aircon load) Not used by TVR
34 Senses if manual or auto gearbox. Manual = 510 ohm resistor, auto = neutral switch TVR wiring diagram does not show this so may not use this. However the pin goes to the clear connector so do not know if resistor fitted in main TVR loom or not. However will fit 510 ohm resistor and then earth anyway as per LandRover diagrams. Orange + Black
35 Input signal from mass air flow sensor - see also pin 25 Blue + light Green
36 Air conditioning condenser blower motor timer relay - output Not used by TVR
37 Not used Not used by TVR. (Shown in 1988/89 wiring diagram as linking to diagnostic socket)
38 (Fault display data, when display module is used) Not used by TVR
39 Engine speed sensor input from the coil 12v -ve terminal. Note that this connector at the coil end has a 6.8k ohm resistor so you cannot check a circuit direct to the coil -ve terminal. Instead test at either side of these connectors which are located near the coil. White + Blue
40 Ground and links to pin 14. Connect direct to ground Black

HTH.
Richard.
Dax Rush 5.0l TVR V8, EFI with Megasquirt ECU and wasted spark, Racelogic Traction Control and Quaife LSD ....... Now nut and bolt restoring a TR6

hybridv8
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Post by hybridv8 »

thanks for your replys,
update is ive got power sorted and ive got a spark,but i carnt get fuel pump relay to start pump?it clicks on and off after about 5 seconds but does not start pump,i can bypass strate to pump with 12v and pump works fine,so not sure where to look..

DaveEFI
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Post by DaveEFI »

I'd guess that is correct. The pump just runs to prime the system for a short time. It will then run again when the ECU sees ignition pulses with the engine cranking or running.
Dave
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unstable load
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Post by unstable load »

I don't know anything about the EFI per se, but from a purely diagnostic point of view, if the pump runs on a direct feed, and the relay is clicking then logic should point to either a burnt set of contacts in the relay preventing current from flowing or a circuit board/wiring issue downstream from the relay.

Replace the relay first and if that isn't successful, troubleshoot the cabling from there to the pump.
Cheers,
John

DaveEFI
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Post by DaveEFI »

unstable load wrote:I don't know anything about the EFI per se, but from a purely diagnostic point of view, if the pump runs on a direct feed, and the relay is clicking then logic should point to either a burnt set of contacts in the relay preventing current from flowing or a circuit board/wiring issue downstream from the relay.

Replace the relay first and if that isn't successful, troubleshoot the cabling from there to the pump.
Note also the relay isn't the most common 5 pin type (SPDT). It is a twin output one, same as the main relay. Some hotwire ones also contain a diode - think they have a red mark. (I've no personal experience of the hotwire, though)
Dave
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hybridv8
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Post by hybridv8 »

thanks all
up and running now,and came second in class at first event. :D

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Post by ChrisJC »

Great news. Just gotta win now!

Chris.
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