captiva

Just to give you some background, with the hope that someone could throw some light on this before I throw 5 litres of gas (petrol) inside it and strike a match, I was just driving along not fast not in boost not nothing if I was doing 40 kph that would be it and the car suddenly started tto misfire and then bog down with a rich, rich mixture (see AFR meter) I limped home and it has never improved. After reading threads on here I put it down to the phase sensor so ordered all new ones and fitted

Phase sensor with correct gap and wires in right place rotor arm lined up with line in dizzy
CPS with right gap and wiggle test on loom
Checked fuel regulator
New dizzy cap
Swopped ECU with another then swapped back
Group A coil is year old, hold ing king wire away from earth has 2 inch spark
New ECT sensor plugged into wiring but not fitted to head as its a bitch
Eliminated IGN pack as spark is so good
Taken apart all 3 wiring gubbins on firewall cleaned and put back
Fuel pump is priming OK
Changed plugs 4 times, keeps soaking them in fuel.
Suspect the rotor arm as when I pull the spark plug leads off when running I used to get a right belter now I dont plus you could get a cracking noise down in valve cover from the giant spark but dont now. Highly unlikely more than one lead would go at once. Tested leads by putting a plug in each one and watching it spark but not the brightest spark .
Pulled off injector wires and momentarily see an improvement.
Tested rotor arm with continuity meter and get only small reading, from centre to end of arm.
Changed MAP sensor


I have tested all resistances and voltages on ECU pins and find no voltage on CPS, supposed to be 2 volts (when cranking) and 0.1 volts on phase sensor (when cranking) tested ignition trigger (not that I know what that is) supposed to be at least 4.5 volts and it is 3.5 volts.

SO I THINK I AM GETTING SOMEWHERE BUT I DON'T KNOW HOW TO FIX IT . Can anyone help . Is the 2 volts created by teeth on pulley rushing past sensor or does or what. Can't think the voltage comes from ECU as it is not even in the car or plugged in for this test (as per instructions)

OAP Pete

May help, as an EX Auto elect now retired i can give you the correct test for the CPS, Best done at the ECU , Remove plug from ECU, measure on OHMs resistance on Pins 3 & 4 to spec below

All OK yes....next test, switch your Meter to AC readings and low value [say 10 / 20 AC ] Meter on pins get someone to crank engine over, you should see to spec below.

OHMS 600-1000K
AC Volts.. 2 /4... depends on how fast Cranking, doing these tests at ECU tests the loom as well.

captiva

Thanks for your reply, I have done exactly this, to the letter, which is how I got to this point where I think I have found the problem but don't know how to fix it as both CPS and phase sensor are brand new. I do get 0.1 volts on the phase sensor which should be 2.0 volts too.The missing voltage cannot be generated through ECU as it is not connected. Any further help would be greatly appreciated as if there were cliffs in Canada I would be pushing it over one.

Chaz888

Correct me if im wrong dos not the edis unit control the cps singnal which is then sent to the ecu?the ecu sends a pwm signal to the edis giving spark adv

OAP Pete

I give the readings for the "Phase sensor in Dizy", OHMS 700-1200....Gap in Dizy of sensor 02-03mm, On what you say i would be inclined to renew Rotor. I say this as you have a good spark from the King lead, One other thing....but sure its OK...check the Dizy is on time with Cams/Crank....expect you have done this....really it should never move....but i remember when i was working going out to a customer who had renewed his Timing belt on Cosy, he had inadvertantly moved the Aux pulley....thinking it was only for the oil pump... engine hardly Ran...OK after i reset all. Just a thought.
The resister in Rotor DOES burn out, ive changed mine twice re-also have Group A coil. Pete.

captiva

Thank you, am suprised I don't get a continuity reading through rotor arm, I didn't know there was a resistor in the rotor arm would this explain no continuity and I have a group a coil which is super powerful it has caught me out several times and when testing it I get a spark jump of 2" to 3"

captiva

Sorry I don't know what an edis unit is please explain.

Chaz888

ho sorry dude Electronic DIStributor on the eec iv its an external unit and eec v internal
have a look for tec notes on the eec-iv mcu by tom cloud its on the net an free to down load dam fine read helped me to understand my cars brain.

captiva

I still can't get away from the fact I have no voltage at CPS or phase sensor but have good resistance readings which must test the wiring and sensor,this must be my problem but how do I correct it?

martysmartie

iTrader: (1)

It sounds like a Cosworth by reading whats said, in which case it has no such thing as a EDIS

To the OP you do have all 4 lugs intact on the crank pulley dont you?

Martin

Chaz888

this is why i spoke of the edis unit maybe theres a problem thare ?

captiva

I do have 4 lugs as this was one of the first things I checked when changing the CPS

captiva

What is EDIS?

captiva

Whoops sorry didn't read the above

Paul_RS

iTrader: (4)

EDIS is only featured on the small turbo escort cosworth.

In regards to the problem, i think a lot of the sensors are daisy chained together?

I forgot to plug my map sensor in and the injectors wouldn't work

Mt tps plug fell of and the car only booseted to 14psi

Its worth checking the wiring to ALL sensors incase the fault lies there

captiva

You're right they are daisy chained together according to the schematic, but when you look at the three that are at fault, the CPS with no voltage, the phase sensor with no voltage and the ignition trigger (what ever that is) that has 3.5 volts instead of the minimum 4.5 volts it is pointing in one direction but as I said before I cannot verify where the voltage comes from so find it hard where to look.

captiva

When I tested the resistance on all these sensors and got the right result didn't that test the wiring?

Chaz888

Sorry dude send you down the wrong road with the edis fluff lol was just thinking surly the cps has a ref voltage from the ecu ? say 5v then the toothed ring effects the mag field at the sensor sending back a htz signal?

Paul_RS

iTrader: (4)

You need an oscilliscope to measure those readings, you'll never pick them up on a multimeter.

@Captiva, testing the sensors like you did doesn't always test the wiring properly.

For example my mates car had an intermittant fault that wouldn't show up on the meters, but did when the car ran. I can only assume the engine vibrations were causing the poor contact?

Just a thought, have you checked the vacuum tubing to the map sensor for holes?