P38A diesel not starting

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Only thing I've done with the nanacom is plugged it in, switched it off then removed it. I'm too frightened to get into the becm in case I made a mess of changing anything.
Can the crankshaft position sensor be checked with an Ohm meter as I'm always cautious of connecting the sensors to one in case I blow it up
 
rover75lover said:
Only thing I've done with the nanacom is plugged it in, switched it off then removed it. I'm too frightened to get into the becm in case I made a mess of changing anything.
Can the crankshaft position sensor be checked with an Ohm meter as I'm always cautious of connecting the sensors to one in case I blow it up
Click to expand...
You can connect the sensor to an ohm meter but it might not tell you much.
 
The CPS should have a set resistance. That resistance should change if a ferrous metal object is moved across the tip. That is the signal picked up by the ECU to denote crank position. Six pulses per revolution twelve pulses per power cycle.
 
1300 ohms, it is logged at as new.
I did a repair on a Hyundai getz... Not a nice car..
Anyhow it was 900 ohms new but this one had the classic "starts from cold but cuts out when hot". The old one measured 580 ohms and would react to a metal object passing.
So.... If it is affected by a passing metal object it may not necessarily be the correct resistance and out of parameters for the ECU.;)
 
Mark Piercy said:
1300 ohms, it is logged at as new.
I did a repair on a Hyundai getz... Not a nice car..
Anyhow it was 900 ohms new but this one had the classic "starts from cold but cuts out when hot". The old one measured 580 ohms and would react to a metal object passing.
So.... If it is affected by a passing metal object it may not necessarily be the correct resistance and out of parameters for the ECU.;)
Click to expand...
The sensors can do funny things. The resistance may change when metal is moved past the tip, but that doesn't mean it will produce a pulse with the waveform needed to operate the input on the ECU.
 
Mark Piercy said:
1300 ohms, it is logged at as new.
I did a repair on a Hyundai getz... Not a nice car..
Anyhow it was 900 ohms new but this one had the classic "starts from cold but cuts out when hot". The old one measured 580 ohms and would react to a metal object passing.
So.... If it is affected by a passing metal object it may not necessarily be the correct resistance and out of parameters for the ECU.;)
Click to expand...

Cuts out when hot sounds like tired FIP.
 
Grrrrrr said:
Cuts out when hot sounds like tired FIP.
Click to expand...

He means the signal from the sensor cuts out when hot not the engine. Even with a duff CPS an engine in good nick with working glow plugs should still start taking readings from number four injector, but it will idle at around 2000 RPM or so. Because the needle lift sensor only sends a signal once every two revolutions.;)
 
wammers said:
He means the signal from the sensor cuts out when hot not the engine. Even with a duff CPS an engine in good nick with working glow plugs should still start taking readings from number four injector, but it will idle at around 2000 RPM or so. Because the needle lift sensor only sends a signal once every two revolutions.;)
Click to expand...

Ah, that does sound like a duff sensor. My miggy cut out when hot until I changed the sensor.
 
Mine seemed duff but there were 2old nuts and a socket bit jammed between sensor/ starter and block from a previous monkey. Only when I removed starter aswell that I found them there. Must of been causing interference since goes fine now hot or cold :cool:
 
RangeRoller dt said:
Mine seemed duff but there were 2old nuts and a socket bit jammed between sensor/ starter and block from a previous monkey. Only when I removed starter aswell that I found them there. Must of been causing interference since goes fine now hot or cold :cool:
Click to expand...

Think of it in a positive sense you sorted it out and gained two nuts and good socket.
 
Update
Changed the cps, no joy.
Rechecked the pump output after the filter head with just turning the ignition. On, 200ml about Decided to remove filter and check output 200 ml so filter OK I assume. Screwed filter back on. Watched the clear pipe as a mate turned it over. Hey presto slackened injector pipes squirting. Did them up she fired straight up! Bear in mind previously I'd bled to the filter head, bled to the pump with a hand bulb primer, slackened all injectors, flattened four batteries and still no injection. She starts cold great, warm the best I've ever known and idles like a purri g kitten. Weird I know
All I have to do now is to get the injector light to stop it flashing when I blip the throttle to 1500 then release, she drops back, almost stalls light flashes then idles. If I rev above 2000 release it doesn't happen
 
rover75lover said:
Update
Changed the cps, no joy.
Rechecked the pump output after the filter head with just turning the ignition. On, 200ml about Decided to remove filter and check output 200 ml so filter OK I assume. Screwed filter back on. Watched the clear pipe as a mate turned it over. Hey presto slackened injector pipes squirting. Did them up she fired straight up! Bear in mind previously I'd bled to the filter head, bled to the pump with a hand bulb primer, slackened all injectors, flattened four batteries and still no injection. She starts cold great, warm the best I've ever known and idles like a purri g kitten. Weird I know
All I have to do now is to get the injector light to stop it flashing when I blip the throttle to 1500 then release, she drops back, almost stalls light flashes then idles. If I rev above 2000 release it doesn't happen
Click to expand...

So it was an airlock? Or you disturbed a wire?

If CEL is flashing there should be a fault stored.
 
Doubt it was an airlock as I flattened the battery four times and used the hand primer to get fuel to the fip.
Might be a wire but I've pulled, wiggled, woggled all I can see and she still starts spot on cold and even hot.
 
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