SafeChav

Which relay is this? What does it do?

DazC

iTrader: (1)

It's the main relay for the KE system. It powers the KE system.....

I am talking S1 and not S2 though....

SafeChav

Oh right, haven't stumbled across one of those before? A pciture would be good if you've got one just for general knowledge. Presumably lives underneath the dash then?

DazC

iTrader: (1)

No picture handy but is is directly next to the silver fuel pump relay above the throttle pedal....

SafeChav

Thats cool. If you ever get the chance to grab a pic of one that would be good.

DazC

iTrader: (1)

I could do but it looks like any other tall black relay!

SafeChav

Do you know what type of relay it is? As in SPST etc? obviously its fused aswell....

DazC

iTrader: (1)

No, I can't remember the exact configuration but IIRC it also has some form of dioded protection circuit in built into it...

vroooom ptssssh

Daz - will i have this relay? i think i have S2 fuel pump wiring?

Certainly got the wiring for the fuel pump relay holder

EFI. . . EFI. . EFI. .

DazC

iTrader: (1)

Jesus christ Dave!! You should have the relay but if not, your KE system may not be working!

I have no way of knowing what your car has or doesn't have. It sounds like it may have been a bit of a bodge up.....no offence intended...

vroooom ptssssh

I know what you mean!

I think their is a relay under the dash, without the cover that was beside the pink relay, iirc their was a spark off it one night . . . say the fuse is blown, what would happen then?

I'll take pics tommoz of what's under the dash, tbh im dreading whats their

Thanks allot for everyones help so far, appreciated

SafeChav

Hello mate!

Right, just been doing some hardcore wire tracing on the diagrams. Firstly:DazC I know the relay you are on about now, kind of left my brain cos as i haven't got one on mine, as i have series 2 management wiring. The said relay is the Fuel Injection MODULE Relay, does everything that the later S2's KE protection module does, and also switches the supply rather than have the feed straight off the ignition switch (same end result),

You said about it having some form of diode...Correct! Its got a Zener protection diode which protects the module from over voltage. Can't see any glass fuse on the internal diagram of the relay but i you seem pretty clued up and it would make sense to have one.

The fuel injection fuse (Fuse R1), supplies the permenantly live feed straight from the Busbar to both the Fuel Pump Relay, aswell as the Fuel Injection Module Relay, and again as DazC said, if the fuel pump is running, then the fuse is ok.

Now, the bit im not convinced about is that its a wiring fault or electrical fault, because as vroooom ptssssh says, once he eventually gets the thing running, and up to temperature its fine. Now i know if there was no feed getting to the KE Jetronic ECU, the car won't cold start well, but it also wouldn't run when well hot, vroooom ptssssh says when its hot the car drives and boosts perfectly.

Cold start enrichment, and full load enrichment (on boost), are controlled solely by the Hydro electric Pressure Actuator, which in turn is controlled by the KE Jetronic ECU.

Its certainly worth a check inside the relay as DazC said, there is a glass fuse in it, but im not convinced thats the problem.

Just for reference aswell while im here, im sure this will help someone else:

The series 1 loom (the wiring from both the ECU's to all the relevant ancilliares) is identical to a series 2 loom, with the following exceptions:

Series 2's had a second CTS (Coolant Temperature Sender) fitted, which gave the IGNITION Module Coolant temperature info (One pin of the sensor connected to pin 8, the other to Negative/Earth)

Series 2's had the Knock Sensor added (One pin connected to Pin 10 of the IGNITION Module, the other connected to Pin 9)

The wiring for both the Series 1 & 2 was identical, (Series 1 loom being minus the 2nd Coolant Sensor, and Knock Sensor, and having a few colour variations) with the following 2 variations (neither of which change functionality)

The Negative/Earth connection of the TPS (Throttle Position Sensor) on the Series 1 loom is connected to Negative/Earth via Pin 6 of the Bosch KE Jetronic ECU, where as the Series 2 loom has the connection as part of a common Negative/Earth point.

The Series 2 loom has additional screening built into the loom (more than likely as an improvement against HT interference)

This means a later ECU can be used on an early car, just aswell as an early ECU can be used on a later car (but the 2nd CTS and Knock Sensor are rendered useless in this combination)

And finally, the loom in its entireity, has only a mere few connections into the cars wiring which is standard through the range:

3 x Black/Yellow wires (4 wires on a series 1, the fourth being to the Series 1 Fuel Pump Relay which was unique), connected to the stater motor cranking wire, providing a feed while cranking for:

Cold Start Valve
Thermo Time Switch
Bosch KE Jetronic Relay (Pin 24)

2 x Black Wires, connected to the main Ignition Relay to supply a switched feed to the coil, and a switched feed to the IGNITION Module.

1 x Black/Green wire (Red on a Series 1), the main OVER VOLTAGE PROTECTED FEED to the Bosch KE Jetronic ECU.

1 x Green wire, from the negative side of the coil, connected to both the Fuel Pump Relay and the rev counter.

vroooom ptssssh

Ok, I gathered in some of that Andy, but im lost on 90% of it

Ok, i have a series 2 engine (came from a D reg car) with what i think to be series 1 wiring/ECU

As far as im aware, their is a plug for every sensor minus the knock sensor, which is ok.

I THINK their are 2 plugs that are different colours, and i assume they were plugged on correct, but this could be wrong
Brown and yellow ring a bell, cold start one is a diff colour, i think, need to check

Anyone know what S1 loom sensor plug colour goes onto S2 engine sensor colour? im SURE their was only 1 plug left and that was a diff colour from the one sensor left unplugged and i knew it wasnt the knock sensor so i put it on the left over plug

So far i have to check:

Fuse under dash (glass fuse)
sensor plug wiring.
accumulator (no fuel pressure in metering head in the morning

I think i need a full new loom

EFI it is then

SafeChav

The wiring plugs your on about are a bitch, they are the same shape/size so its easy to get them wrong, and the 2 down the back of the block, are the 2 that are closest in colour, almost impossible to tell apart when they get dirty.

At the back of the engine there is:

CTS (Yellow Plug)
Thermo Time Switch (Brown Plug) if your cold start is disconnected this can stay disconnected too.
Cold Start Valve (Blue Plug)

The knock sensor is green, and yes you will not have a plug for it. Also being an engine from a D plate S2 it wont have the 2nd CTS (which would be redundant anyway)

That yellow plug is VERY important (and as luck would have it its also the hardest 1 to plug in ), that could make your cold start problem if its not connected on the right sensor........its what tells the ECU to enrichen the mixture when cold.

Your fusebox is a MK3 1, so i would say it is a series 1 loom. The ecu's should make no odds, but i believe a series 1 IGNITION module will have BLUE RED BLUE colour code, and the KE Jetronic ECU will have a BLUE sticker on it.

Stu @ M Developments

iTrader: (12)

Car will run perfectly once hot, but it will be lean enough to meltdown on high boost. You cannot really "Feel" teh difference between 11.5:1 and 13.5:1 in most scenarios.

Running the Knock sensor ecu without one will result in a VERY flat timing curve, the ecu needs it to be present.

The 2 boxes should either be fitted to their correct looms or be changed internally to match the alternative harness.

davidnormanuk

The heated seat fuse on a seroes 2 sends power to somewhere in the black fuel ECU. I got told this by well lane turbos when i took my RS there. When the car is running on tickover you pull the fuse out and then just touch the two terminals with the fuse creating a cicuit and the car should stutter slightly. This is a way of checking the fuel ecu is working correctly. I had this problem when doing the conversion on mine. I had 3 black boxes and only 1 of them was working correctly.

SafeChav

Agreed, it will rum smoothly i believe is more the word, with no enrichment the boost won't actually make the car pull as it should, which i found when i had a TPS failure, (which is the sensor which triggers full load enrichment). I also had a time where the main earths for the ECU's got left off, and the thing was a bitch to cold start, but once hot would idle, but not very well and boost didn't pull.

No enrichment, no proper boosting power!

SafeChav

Forgot to say about knock sensors, guess it falls down to personal preference, i see people with sensors unplugged, and ive heard people saying that the knock sensors can be affected by a noisy top end.

Me personally i run one, but then there is a lot of powerful series 1's out there, and they never had them, so............they can't be that crucial.

vroooom ptssssh

Where do the earths go on the ECU's? are they in the multi plug or seperate?

SafeChav

Ummmmm, now your asking, on a S2 loom, there is 3 thin brown wires with ring terminals on, and they go on the battery, i would of thought its the same on your S1. Just check theres no wires running stray round the battery area.

Just to clarify aswell, when your car is hot and running ok, does it boost PROPERLY, does it have the same pull and throw you back in the seat or is it quite gutless?

vroooom ptssssh

Same as any standard rst when it was running 7psi when set up, perfect! But remember i said about it boosting to 12psi now, (i have no explanation for this ) When accelerating hard it hesitates, pops and bangs from exhaust, but it has only done that a few times on one night, its not been floored hard since just incase, I thought it was down to my shit plug leads.

Made 106@wheels on the RR std boost/ignition timing etc, 2bhp down from standard.

DazC

iTrader: (1)

The above applies to an S2 only......

The knock sensor MUST be connected as the ECU will retard the ignition. Personnal preference or not, disconnection means flat ignition curve (curve being the incorrect word, more like the side profile of a flight of stairs). Best thing to do is take the sensor out of the manifold and leave it plugged in but secure it to the loom some where.

The S1 ECU didn't have the sensor as it had no software in it's ECU to utilise the sensor.

SafeChav

Where does the rev counter and fuel pump relay get the LT pulses from then????

I said about the knock sensor in the big write up:

With having it unplugged i was referring to series 2's i have seen. I have mine plugged in, no reason not to

DazC

iTrader: (1)

The S1 uses a pulse from the coil negative to run the rev counter but the fuel pump relay has a pulse from the ECU itself (on pin 20 or 25 IIRC).

I know you said about the knock sensor being fitted to the S2 and not the S1, but you still said that the sensor being connected is personall preference. I was just passing comment that without it connected, the S2 ECU goes into a "limp home mode" and flattens the ignition curve and reduces power. Without the ignition advance, the car will make boost but not feel as lively (I.E shit, and noticably slower if it had full use of maximum ignition advance).

SafeChav

From the revcounter its Green/Red, to the fuel pump,then Green from the revcounter to the coil, then looped back round to Pin 1 on the ignition module, exactly the same as the series 2. Well, when i say EXACTLY they are all still looped through, the rev counter, ecu and coil all share the same connections of the LT side.

I know were tyou passing comment about the ECU likewise we all are, DazRS has a Series 2, and his knock sensor is disconnected, hes getting 225bhp @ 18psi i believe?

I have pages from the official Bosch management manual, i don't remember seeing about it saying it goes into limpback if the knock sensor is disconnected, but ill re-read it its been some time.

This is turning into quite a useful thread for some i would hope

vroooom ptssssh

Ok, lets summarise (i you can be assed )

wiring faults that can effect my cars cold starting:
Power to black fuel computer (working i assume as my car runs fine when warm?)
ECU/fuel computer earths
black relay/fuse

(anyone any more to add?)

mechanical things that can effect cold start:
accumulator
mixture? assume it is ok
I think i read the fuel pump relay sends signal to warm up regulator or something on:
http://www.auto-solve.com/mech_inj.htm
"The voltage supply to the regulator is from the fuel pump relay, because if the ignition was on without the engine running, all enrichment would be removed as the bi-metalic strip would be heated prematurely and the driver would not benefit from the cold engine enrichment"
Do i have a Warm-up-Regulator?

Anything else anyone can add, i need a list of things to check/fix.

thanks again

SafeChav

The signal sending bit your talking about is for K Jetronic, the Speed sensor relay controls partly the warm up regulator, but is N/A to yours.

davidnormanuk

Out of interest try swapping the black ECU with a known good one. I had one that was a get to start but would run great when warm. Then I had one that wouldn't increase the fuelling properly on boost. Swapped it with a known good one and all is well. No sensor changes or anything.

vroooom ptssssh

davidnormanuk, will give it a try mate, but i will need to source someone with one

S1 Barkham

Are you sure it's not a dodgy metering head that leaks fuel pressure when stopped, therefore having to crank it that extra to build the pressure back up before it'll fire? As i think i have this problem with my S1, however EFi would be the better option

SafeChav

S1 Barkham: It could well be, i believe we are still just putting ideas into the pan for him to work around and try, he says he thinks he has a low fuel pressure.

As for yours, are you sure its the metering head, i had a low fuel pressure on mine and it was the tiniest part that i didn't even know existed!

vroooom ptssssh

Pretty sure it deosnt leak, it wont turn over for ages then fire, it just turns over. . and over. . unless i hold the flap down 5mm and get someone to crank it.

DazC

iTrader: (1)

Wrong!!

On the S1, the coil negative is connected to pin 1 on the ignition ECU and the other green wire goes to the rev counter. The hall effect sensor in the dizzy is connected to pin 20 (green/yellow) on the ignition ECU, then from pin 20 (green/red) to pin 1 on the fuel pump relay and pin 25 (green/red) on the fuel ECU.

Regardless of this fact, unless the ECU has been modified or he runs a blue red blue or a blue red white ECU then he will have a flatter ignition curve than he could be running.

You won't find it in the Bosch manual because it's Fords own ESC 2 ignition ECU. It has nothing to do with the Bosch fuel system, which operated completely seperately to the ignition system.

1.9 xr2 on 40's

my tupence is

not all s2's have knock sensors, most d plates dont

this point may be irrelevent but bollox to reading all to the above

i have stock piles of s2 early inlets with out knock sensors

DazC

iTrader: (1)

Quite correct mate. The D plate cars had the blue red white ECU without knock control.

vroooom ptssssh

My engine came from a Dplate car, wether it was original engine i dont know, but it has a knock sensor, which is obf not plugged in.

if i was running the incorerect ECU then AVA would of noticed im sure, and i wouldnt of made 106@the wheels on std set-up

S1 Barkham

I would say the fact your having to depress the metering flap indicates some sort of fuel problem. Which will more than likely be a dodgy metering head. If was you i'd either get it checked over by a pro, or swap it for one you know works.

vroooom ptssssh

Something doesnt seem to be right if their is no fuel pressure, either accumulator
one way valve at fuel pump not operating properly
metering unit leaking/fuel line leaking (pretty sure neither of them are)

SafeChav

Are you sure about that wiring, the Ford diagram suggets different...

His ECU is a Heart Diamand Hash, so your saying with the knock sensor plugged in the power would raise even more?

Thats a good point on the ECU, thats why i dont remember seeing anything about it At least someone is on the ball

DazC

iTrader: (1)

I am 100% sure I am correct.

Not only do I have the Ford wiring diagram for the Series 1, I have 3 of them and also wiring diagrams for the S2 86-88 spec and 90 spec wiring diagrams. The S1 diagram confirms that my experience with my own car and MJC's car off here and the RSOC is 100% correct.

Unless his ECU has been modified to exclude knock control, he may well increase his power just by removing it from his manifold and plugging it in, then having it set back up again. It may have been possible that static ignition timing may over come the retard in the ECU by having it run excessively advanced at idle..