wolf cosworth

Good morning ,

cosworth 4x4 92 , dark greens , close loop , MSD stage 2 ( manually limited 1,3 bar no amal valve ) , scorpion exhaust no cat ,T3 hybrid,group A coil, blue ignition leads, RS500 cooler, pipercross cone under fender, 3 bar MAP,-31 actuator.

I changed the distributer cap , rotor , new denso plugs.
Lambda gives signs of being rich above 3000 RPM , fuel pressure is nicely rising with the turbo pressure.

Car drives great only when coming on boost above 3500RPM , RPM meter dances like crazy and by 5000RPM sounds like rev limiter comes in ???
When boost is brought down to like standard 0.8 bar it is happening almost not


Gaps on the crank and the ditributor are OK and these sensors I replaced like 10000km ago .

Not sure what to do next ...

Steven

JamesH

iTrader: (21)

Crank position sensor, if not this, then move to the phase sensor in the dizzy!

wolf cosworth

crank sensor was at 0,65mm so cannot be the problem either

RS500/364

ICV not working correct

wolf cosworth

Did the checks below not all there I am alone and cranking the engine and measuring is not so easy but my worry goes out to NR16 what is to low should be 4.5 V is reading 3,6 V what is the ignation trigger actually ?

BASIC FAULT FINDING GUIDE FOR COSSIE ECUS
My battery voltage at battery was 13.52V ( charging )

NOTE: Some of these results can be affected by an alarm system or immobilizer. I have assumed the car has a 2.5 bar/3.0 bar map sensor.
If SECS monitor is fitted, unplug it! (A faulty monitor or incorrectly fitted can cause engine not to run)

1) Ensure ignition is OFF.
2) Remove rear of ecu plug cover and insert plug back into ecu.
3) Turn ignition back on (do not start engine)
4) MAIN POWER CHECK: Check for DC voltage of at least 11.5V between ecu pins 19 and 20. 12.35V
5) REFERENCE CHECK: Check for DC voltage of around 4.8 to 5.2V between pins 11 and 30. 4.94V
6) MAP SENSOR CHECK: Check for DC voltage of approx 1.8 to 2.5V between pins 11 and 15. 1.56V
7) THROTTLE CLOSED:
4x4: Check for DC voltage less than 0.5V between pins 11 and 17. 0.16V
2WD: Check for DC voltage greater than 4.5V between pins 11 and 17.
8) THROTTLE FULLY OPEN:
4x4: Check for DC voltage greater than 4.5V between pins 11 and 17.
2WD: check for DC voltage less than 0.5V between pins 11 and 17.
9) Turn ignition off, unplug ecu, turn ignition back on (don’t forget immobilizer if fitted)
10) CRANK SENSOR: Check resistance between pins 3 and 4 between 300 and 1200 ohms. 682 Ohms
11) CRANK SENSOR: Check AC voltage on pins 3 and 4 while cranking engine - should be at least 2V.
11) PHASE SENSOR: Check resistance between pins 5 and 23 between 300 and 1200 ohms. 795 Ohms
12) PHASE SENSOR: Check AC voltage on pins 5 and 23 while cranking engine - should be at
least 1.5 - 2V.
12) INJECTOR: Check resistance from pins 18 to 20 should be 2 to 5 ohms. 5 Ohm
13) INJECTOR: Check resistance from pins 35 to 20 should be 2 to 5 ohms. 5.1 Ohm
14) INJECTOR: Check resistance from pins 33 to 20 should be 2 to 5 ohms. 5.1 Ohm
15) INJECTOR: Check resistance from pins 32 to 20 should be 2 to 5 ohms. 5 Ohm
NOTE: INJECTOR TESTS MAY NEED MAIN RELAY ENERGISED ON L1 and L6 ecus (link pins 1 and 10 first)
16) IGNITION TRIGGER: Read voltage between pins 24 and 25, should be at least 4.5V. 3.6V
17) IGNITION TEST: BEWARE DANGEROUS VOLTAGES ON PLUG/COIL LEADS.
Quickly link pins 24 and 25 on and off this will FIRE the ignition coil. Rotate dizzy by moving car in gear to point rotor arm at one plug lead and remove spark plug (earthing it on chassis or engine) to see spark. Try for each plug in turn. Or remove king lead at dizzy and place end within 1 centimetre of earth to see a big spark.
18) Place a temporary wire link from pin 1 to pin 10 (energises ecu power relay) - you should hear a click.
19) Quickly link pins 19 to 28 to test fuel pump runs.
20) COOLANT TEMP: Check resistance pins 29 and 11 for 800 ohms to 5000 ohms (depends on temp) 3.84 K Ohms
21) CHARGE TEMP: Check resistance pins 31 and 11 for 800 ohms to 5000 ohms (depends on temp) 4.11K Ohms

wolf cosworth

has indeed some problesm not running idle correctly but not always .
Can I measure this one ?

pee vee

multi plugs on the bulkhead above the cam cover.. mine were a bit dodgy and gave this exact problem..

i'd replace the multi plugs personally.. but some people have chopped them off and joined the wires direct.

wolf cosworth

did this start the engine cold 800RPM's disconnect ICV dropped to 400 PRM connect back and engine runs back at 800 so I assume this one works ?

wolf cosworth

Will spray the multiplugs and then see over the weekend if it made any difference otherwise I will joine the wires directly.

turbo taylor

iTrader: (2)

i have the exact same problem as you the multi plugs is causing me trouble im going to replace the crank sensor and see how i get on from there but i will probably chop the plugs and join them

wolf cosworth

Cut the connectors yesterday out of the loom and "welded" the wires them together no problems anymore thx for helping

pee vee

the rev counter dancing about was the clue!